(<<) ) ~~ TECHNICAL REPORT CERC-84-1 ANNUAL DATA SUMMARY FOR 1980, of Engineers. CERC FIELD RESEARCH FACILITY H. Carl Miller Coastal Engineering Research Center U. S. Army Engineer Waterways Experiment Station P. O. Box 631, Vicksburg, Miss. 39180 WHO! DOCUMENT COLLECTION fe February 1984 Final Report Approved For Public Release; Distribution Unlimited Prepared for Office, Chief of Engineers, U. S. Army Washington, D. C. 20314 Destroy this report when no longer needed. Do not return it to the originator. The findings in this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents. The contents of this report are not to be used for advertising, publication, or promotional purposes. Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products. WOMAN AO O 0301 0091244 9 Unclassified SECURITY CLASSIFICATION OF THIS PAGE (When Data Entered) REPORT DOCUMENTATION PAGE 1, REPORT NUMBER 2. GOVT ACCESSION NO, 3. RECIPIENT'S CATALOG NUMBER Technical Report CERC-84-1 5. TYPE OF REPORT & PERIOD COVERED 4. TITLE (and Subtitle) ANNUAL DATA SUMMARY FOR 1980, CERC FIELD RESEARCH FACILITY Final report 6. PERFORMING ORG. REPORT NUMBER 8. CONTRACT OR GRANT NUMBER(s) 7. AUTHOR(s) H. Carl Miller PERFORMING ORGANIZATION NAME AND ADDRESS OGRAM ELEMENT, PROJECT, TASK EA w U a ORK UNIT NUMBERS U. S. Army Engineer Waterways Experiment Station Coastal Engineering Research Center P. O. Box 631, Vicksburg, Miss. 39180 11. CONTROLLING OFFICE NAME AND ADDRESS Office, Chief of Engineers, U. S. Army Washington, D. C. 20314 Waves and Coastal Flooding Program 12. REPORT DATE February 1984 13. NUMBER OF PAGES 167 SECURITY CLASS. (of this report) iS? 14. MONITORING AGENCY NAME & ADDRESS(i/f different from Controlling Office) Unclassified 15a. DECLASSIFICATION/ DOWNGRADING SCHEDULE 16. DISTRIBUTION STATEMENT (of this Report) Approved for public release; distribution unlimited. DISTRIBUTION STATEMENT (of the abstract entered in Block 20, if different from Report) (RAS 18. SUPPLEMENTARY NOTES Available from National Technical Information Service, 5285 Port Royal Road, Springfield, Va. 22161. 19. KEY WORDS (Continue on reverse side if necessary and identify by block number) Meteorological research--Statistics (LC) Oceanographic research--Statistics (LC) Oceanographic research stations--North Carolina--Duck @G) Water waves--Statistics (LC) 20. ABSTRACT (Continue an reverse side ff neceseaary and identify by block number) This report provides basic data and summaries of the measurements made dur ing 1980 at the U. S. Army Engineer Waterways Experiment Station (WES) Coastal Engineering Research Center's Field Research Facility (FRF) in Duck, N. C. The report is the second in a series of annual summaries of data collected at the FRF; the first, which summarizes data collected during 1977-79, was published as Coastal Engineering Research Center Miscellaneous Report 82-16 and is available from the WES Technical Report Distribution Section, Vicksburg, Miss. FORD DD . jana 1473 EvrTion oF 1 Nov 6515 OBSOLETE Unclassified SECURITY CLASSIFICATION OF THIS PASE (When Data Entered) SECURITY CLASSIFICATION OF THIS PAGE(When Data Entered) EE SECURITY CLASSIFICATION OF THIS PAGE(When Data Entered) PREFACE Data and data summaries presented herein were collected during 1980 and compiled at the U. S. Army Engineer Waterways Experiment Station (WES) Coastal Engineering Research Center's (CERC) Field Research Facility (FRF) in Duck, N. C. This report, the second of a series of annual FRF data collection sum- maries, was carried out under CERC's Waves and Coastal Flooding Program. The report was prepared by H. Carl Miller, Oceanographer, under the supervision of Curt Mason, Chief, FRF Group, Research Division. The author acknowledges the entire FRF Group for their efforts related to instrumenta- tion, data collection, and analysis. Drs. Robert W. Whalin and Lewis E. Link, Chief and Assistant Chief, respectively, of CERC, and Dr. James R. Houston, Chief, Research Division, provided general guidance. In addition, a special thank you is extended to the National Oceanic and Atmospheric Administration (NOAA) National Weather Service, who helped with the anemometer, NOAA/National Ocean Service, who maintained the tide gage and provided analysis results, and to S. Jeffress Williams, formerly of CERC, who provided the October sediment survey data. Commander and Director of WES during the publication of this report was COL Tilford C. Creel, CE. Mr. F. R. Brown was Technical Director. CONTENTS PREFACE . LIST OF TABLES LIST OF FIGURES CONVERSION FACTORS, INCH-POUND TO METRIC (SI) UNITS OF MEASUREMENT PART I: INTRODUCTION . PART II: CLIMATOLOGICAL SUMMARY PART III: INSTRUMENTATION Wave Gages Ebon paid e:sGapreSiiimereattamveers. psec ts Meteorological Instruments PART IV: DATA COLLECTION AND ANALYSIS Digital Wave Data . Water Level Data Re eee Weather and Visual Observations Bathymetric and Pier Surveys Photography . Puerco Sediment Data . PART V: DATA AVAILABILITY/RESULTS Data Availability . Results ean’ REFERENCES APPENDIX A: METEOROLOGICAL DATA APPENDIX B: WAVE DATA APPENDIX C: SURVEY DATA LIST OF TABLES 1980 Calibration/Maintenance Schedule for Baylor Staff Gages Waverider Predeployment Calibration Information, 1 August 1980 . 1980 Data Availability Meteorological Data Summary for 1980 Monthly Precipitation Means, Maxima, and Minima at the FRF from 1978 through 1980 Seasonal Significant Wave Height Statistics for 1980 Seasonal Peak Wave Period Statistics for 1980 . 13 18 36 37 38 51 51 ON F&F Ww HY & 19 20 21 22 23 Tide Statistics for 1980 1980 Aerial Photography Inventory . Statistical Parameters of the 1980 Foreshore Sand Samples LIST OF FIGURES FRF location map FRF instrument locations Amplifier zero drift during 1980 Predeployment Waverider gage calibrations Sample chart records for the microbarograph, rain gage, and pyranograph Quarterly aerial photography flight lines, 1980 Monthly high and low air temperatures, 1980 Times of wind direction change, 1980 Weather map for 3 March 1980 1980 annual wind rose for the FRF, reference true north . 1980 monthly wind roses for the FRF . 1980 seasonal wind roses for the FRF, reference true north Tracks of 1980 hurricane storms affecting the FRF . Annual and seasonal resultant wind speed and direction for the FRF, 1980 1980 annual wave height distributions 1980 annual wave period distributions Directional wave summaries for 1980 Seasonal wave roses for the seaward end of the FRF pier, reference Beach 0 to 180 deg . Monthly tidal means and extremes for the seaward end of the FRF pier, 1980 Hourly tide height distribution, 1980 Distribution of 1980 daily highest and lowest tide levels, referenced to NGVD Sea surface temperatures, 1980, for the seaward end of the FRF pier . Annual and seasonal distributions of sea surface temperatures, 1980, at the FRF Page 56 73 75 54 Dill Sy 58 60 60 No. 24 25 26 27 28 29 30 31 32 33 34 39 36 3i7/ Air/Water temperature differences, 1980, for the seaward end of the FRF pier . Water visibility, 1980, for the seaward end of the FRF pier . Distribution of visibility measurements, 1980, at the FRF . Surface current speed, 1980, at the seaward end of the FRF pier . Surface current speed and direction, 1980, measured 500 m updrift of the FRF pier FRF bathymetry for October 1980 . Pier profile envelopes, April-September 1980 Pier profile envelopes, January-March and October-December 1980 . Bottom elevation changes along the FRF pier, 1980 . Beach photographs looking north from the FRF pier . Sample aerial photograph of the FRF taken 16 July 1980 RSA-determined mean grain size of the foreshore samples taken 500 m north of the FRF pier in 1980 . Sediment sample locations for October 1980 survey . Mean sediment grain size and position along the October 1980 survey line Page 62 64 64 65 66 67 69 70 71 12, 74 ial, 79 80 CONVERSION FACTORS, INCH-POUND TO METRIC (SI) UNITS OF MEASUREMENTS Inch-pound units of measurement used in this report can be converted to metric (SI) units as follows: Multiply By To Obtain acres 0.4046873 hectares feet 0.3048 meters millibars 100.0 pascals ANNUAL DATA SUMMARY FOR 1980, CERC FIELD RESEARCH FACILITY PART I: INTRODUCTION 1. The U. S. Army Engineer Waterways Experiment Station Coastal Engi- neering Research Center's (CERC) Field Research Facility (FRF) located on 176 acres* at Duck, North Carolina (Figure 1), consists of a 561-m-long re- search pier and an accompanying office building. The FRF is located near the middle of Currituck Spit along a 100-km unbroken stretch of shoreline extend- ing south from Rudee Inlet in Virginia to Oregon Inlet, North Carolina. It is bordered by the Atlantic Ocean to the east and Currituck Sound to the west. The Facility is designed to (a) provide a rigid platform from which waves, currents, water levels, and bottom elevations can be measured, especially during severe storms; (b) provide CERC with field experience and data to com- plement laboratory and analytical studies and numerical models; (c) provide a manned field facility for testing new instrumentation; and (d) serve as a permanent field base of operations for physical and biological studies of the site and adjacent region. 2. The research pier is a reinforced concrete structure supported on 0.9-m-diameter steel piles spaced 12.2 m apart along the pier length and 4.6 m apart across the width. The piles are embedded approximately 20 m below the ocean bottom. The pier deck is 6.1 m wide and extends from behind the dune line to about: the 6-m water depth contour at a height of 7.8 m above mean sea level. The pilings are protected against sand abrasion by concrete erosion collars and against corrosion by a cathodic system. 3. A FRF Measurements and Analysis (FRFMA) program has been established to collect basic oceanographic and meteorological data at the site, reduce and analyze these data, and publish the results. 4. This report is the second in a series of annual reports and summa- rizes the data collected during 1980. It is organized such that descriptions of the instrumentation, including sensor calibration and maintenance (Part III) and data collection and analysis procedures (Part IV) precede reporting of the J ray A table of factors for converting inch-pound units of measurement to metric (SI) units is presented on page 5. dew uworjzeco,T qyq ‘TL eansTy VNITOUVD HisON sustae i) fs mao sum 4 ee. 3 \ AMMIVI HIBVISIY C1313 Ne i) data (Part V). Although this is intended as a stand-alone document, details of some procedures and instrumentation are given in the references. 5. Future annual reports will have approximately the same format; readers' comments on the format and usefulness of the data presented are en- couraged. 6. In addition to the annual reports, monthly data reports summarizing the same types of data shortly after the data are collected are available to requestors from the CERC Field Research Facility, S. R. Box 271, Kitty Hawk, North Carolina 27949. 7. The CERC Coastal Engineering Information Analysis Center (CEIAC) is responsible for storing and disseminating most of the data presented or al- luded to in this report. All data requests should be in writing and addressed to Commander and Director, U. S. Army Engineer Waterways Experiment Station, ATIN: CEIAC, P. 0: Box 6315. Vicksburg, Mississippi’ 39180... Tidal data other than the summaries in this report should be obtained directly from the Tides Branch, National Ocean Service (NOS), Rockville, Maryland 20850. A complete explanation of the exact data desired for specific dates or times will expe- dite filling any request; an explanation of how the data will be used will help CEIAC or NOS determine if other relevant data are available. For infor- mation regarding the availability of data, contact CEIAC at (601) 634-2017. Costs for collecting, copying, and mailing will be borne by the requester. PART II: CLIMATOLOGICAL SUMMARY 8. This section provides a brief summary of the environmental condi- tions at the FRF during the reporting period; complete tabulated summaries are contained in Part V. 9. The maritime climate at the FRF tends to moderate the seasons, pro- ducing winters that are warmer and summers that tend to be cooler than on the mainland. Large temperature differences between day and night occur during late fall and spring due to the slow response of the ocean to changing temper- ature trends and frequent land and sea breeze effects. Air and water tempera~ tures at the FRF tend to be lowest in February and highest in July and August. 10. The precipitation was fairly well distributed throughout the year; the monthly average during 1980 was 68 mm. May was the wettest month (112 mm), while September was the driest (30 mm). 11. A persistent breeze, warm in summer and chilly in winter, blows at the FRF; seldom is it dead calm. On occasion, severe winds blow as a result of either extratropical cyclones (northeasters) or tropical cyclones (hurricanes). 12. The summer winds are predominantly from the southwest, while winter winds blow out of northern directions. Extreme winds generally came from the north-northeast. Although the FRF was not directly hit by a major hurricane in 1980, strong northeasters produced winds in excess of 15 m/second. 13. The wave heights at the FRF vary as a function of water depth and season. Generally, the deeper the water, the larger the wave conditions. The annual average significant wave height for 1980 at the seaward end of the pier (8-m depth) was 0.87 m (0.44 m standard deviation), with an average peak spectral period of 9 seconds (2.8 seconds standard deviation). Wave heights tended to be lowest from April through September and greatest during January through March. 14. Surface currents are strongest and move predominantly southward during the winter and are much more frequently directed northward in the summer. 15. The tides at the FRF are semidiurnal, with 2 high and 2 low tides generally occurring daily with a tide range of slightly more than 1.0 m. Local mean sea level during 1980 was 8 cm above the local 1929 National Geo- detic Vertical Datum (NGVD). The extreme high tide was 118 cm NGVD observed on 2 March, while the lowest tide was -119 cm NGVD observed on 16 March. 16. The depth contours are relatively straight and parallel to the coast in the vicinity of the FRF with the exception of the area immediately adjacent to the pier. Here the contours bend drastically toward shore (a) as much as 250 m at the 7-m depth contour (i.e., normally seaward of the end of the pier) and (b) 20 m at the 3-m depth contour (i.e., near the beach). Fre- quently a bar is present nearshore, while occasionally a two-bar system is evident. 17. The sand size varies both temporally and spatially at the FRF. In 1980, foreshore sizes during the low-wave condition of summer tended to be finer than at the high-energy periods during winter. The surface sediments on the beach tend to be fine-to-medium-fine-grained, with relatively coarse, poorly sorted sands at the beach step; a shell fraction is also evident. Sands offshore tend to become increasingly fine, with moderately well-sorted very-fine-to-fine quartz sand out to the -17 m contour. 10 PART III: INSTRUMENTATION 18. This part identifies the instruments used for long-term monitoring of oceanographic and meteorological conditions and briefly describes their design and operation. More detailed explanations can be found in Miller (1980). Equipment (i.e. the surveying system) used for collecting other types of data is discussed in Part IV. Wave Gages 19. Five wave gages were operated in 1980 as part of the FRFMA for monitoring wave conditions in the vicinity of the FRF (Figure 2). These in- cluded a wave staff gage on Jennette's Fishing Pier in Nags Head, N. C., approximately 40 km south of the FRF; two wave staff gages on the FRF pier (one at station 6+20 (hundreds of feet), the other at station 19+00); and two Waverider buoy gages located 0.6 and 3 km offshore. Staff gages 20. The wave staffs were parallel cable types manufactured by the Baylor Company, Houston, Texas, and were designed for an accuracy and resolu- tion of 1 and 0.1 percent full scale, respectively. The Baylor gages required little maintenance except to keep the cables taut and free of anything which could cause. an electrical short across them, i.e. fishermen's nets, ropes, biological fouling, etc. Defective parts required replacement; this type of gage (specifically the transducer elements) is susceptible to lightning damage. 21. The transducer elements were connected to test cables in the labo- ratory and calibrated prior to installation by placing an electrical short between the cables at known distances and noting the voltage output from the transducer. In the field, electronic signal conditioning amplifiers were used to ensure the output signal from the gage was within a O- to 5-V range. The transducer elements and signal conditioning electronics held their calibra- tions very well; differences greater than 1 percent full scale were unusual. Table 1 shows the dates when calibration/maintenance was performed for the Baylor staff gages. 22. Since the Baylor staff gages actually sense the water level on the gage, a 20-minute average of the levels measured four times per second can be 1 000€ 0082 0092 O0Ke 00+ 28 00+ +8 00+ 18 00+ 82 o o wu dod + + oo o Oo 00+S2 00+ ¢2 00+ 69 00+ 99 029 ON ‘Aong sapisaaom 2404S)j0 00¢2 0002 008! 00+ €9 B16! ‘Aaasng rjsawAyjog sawwNg wos 0400 SUOTJEIOL JUaWNAYSUT Fy_ “7% 9ansTy 009 | 00+09 00+ 2S 00+%S 00+ 1S Janay 0aS uoaw oor! (w) a2u0)s1G 0021 000! 008 009 00 002 te) 002- O00b- 009- 008- 000!- (4) 30 Spaspuny) JaquAN YOI}OIS Se &buww ww wnwn ww - - - Pi les a en oe eects SZBanonwoon es — © AN O HD YF wr on © @O- & NO at rapa ee ote Gt eee ee ++ eeeeerere et coooooooooeooee fo & ooooo ooo fo @ tart tt = = > > > Se- Ol- 09- 02 0s - GI- 6261 Puo QZ61 bulang shaasns Ov- QuIT-poa) wWOss SU0IyOAa|Z UOIPAW o¢c- = WO!- at o2-= o- 019 ON ‘hong sapisaaom as0yss02N Ol- = ee 0 3 do Ol == ¢ 09 +6) 19 (OLE1-S98 SON) 2609 api, pu3z-said Jdj9YS JUaWNI ISU] J94IO3M 02: a6o9 uloy o€ 01 00461 10 (S29°ON) 2609 401409 1104 puoH yajyawowauy Ob TSW aA0gy WO9'Z 4920 Jaid os S| (dag saije) Jayawowsauy 09 02 NVIIO JDIANVILV = hong sapisaa0m 2104S)j40 YyJON ON, 02+9 10 (S19°ON) 2609 10)h0g ONNOS NINLIAYNID 02+9 10 2609 s0)h0g 2609 apt, puz-saId buipying Jald 00+6) 10 2609 301409 7 Jajawowauy (UO casi fh dwoy i) Bny 0}) sa}awOowsUuy Aong J9p1JaA0M a40YS409N © Ce. ULI: ee pooy s$ar0y OL+L - Jaljayg juawNysul G6+0 - 3e aBedH uley Ul-ZL (98qQ-das) OZ+0 ‘(6ny-uer) G9+0 - Ie JalaWoWouYy OO+L 02 O+0 SuIpliINg 4ald (w) uo1joaas3 12 Table 1 1980 Calibration/Maintenance Schedule for Baylor Staff Gages Gage Date Calibration/Maintenance Performed 112 11 Apr Amplifiers calibrated (Nags Head) 22 Apr Replacement calibrated transducer was installed 10 Jul Replacement calibrated transducer and amplifiers were installed 625 8 Jan Cleaned and tightened cables (Baylor gage 9 Jan Replacement calibrated transducer was installed and amplifiers at 19+00) were calibrated 22 Jan Calibrated amplifier 31 Jan Replacement calibrated transducer installed and amplifiers calibrated 11 Feb Calibrated amplifiers 27 Feb Replacement calibrated transducer with lightning protection circuit installed 27 Mar Calibrated amplifiers; -3 percent error full scale noted 16 Apr Calibrated amplifiers 13 Jun Calibrated amplifiers 28 Jun Calibrated amplifier 8 Jul Replaced IC's in amplifier and calibrated 24 Jul Cleaned cables 28 Jul Calibrated amplifiers 11 Aug Changed data cables and calibrated amplifiers 22 Aug Calibrated amplifiers 28 Aug Calibrated amplifiers 23 Sep Calibrated amplifiers 27 Sep Calibrated amplifiers 3 Oct Calibrated amplifiers 4 Oct Calibrated amplifiers 14 Oct Calibrated amplifiers 21 Oct Calibrated amplifiers 31 Oct Calibrated amplifiers 4 Nov Replacement calibrated transducer installed 13 Nov Calibrated amplifiers 20 Nov Calibrated amplifiers 1 Dec Calibrated amplifiers 10 Dec Calibrated amplifiers 15 Dec Replacement calibrated transducer installed 615 22 Jar Calibrated amplifiers (Baylor gage 14 Feb Calibrated amplifiers at 6+20) 17 Mar Calibrated amplifiers 16 Apr. Calibrated amplifiers; 2 percent error full scale noted 22 Apr Calibrated amplifiers 28 May Calibrated amplifiers 13 Jun Calibrated amplifiers 5 Jul Amplifiers repaired 7 Jul Replacement calibrated transducer installed and amplifiers calibrated 24 Jul Cleaned cables 22 Aug Calibrated amplifiers 22 Sep Calibrated amplifiers 27 Sep Calibrated amplifiers 3 Oct Calibrated amplifiers 14 Oct Calibrated amplifiers 21 Oct Calibrated amplifiers 31 Oct Calibrated amplifiers 13 Nov Calibrated amplifiers 20 Nov Calibrated amplifiers 1 Dec Calibrated amplifiers 10 Dec Calibrated amplifiers used to provide a mean sea (or tide) level. (It was suggested that the Baylor staff gages along the FRF pier be used to measure water levels across the surf zone to investigate the water's slope. This was not pursued because the gage zero value showed both a random variation due to the difficulty in measuring the zero offset and a time-dependent change due to amplifier drift.) 23. The procedure used to monitor the gage zero level was to measure the water level on the gage and gage output, then compare that to the corre- sponding gage output for the measured water level based on the gage calibra- tion curve. Differences implied a drift of the gage zero. In practice, this was accomplished as follows: a. The distance from the pier deck to the still-water level was measured by lowering a weighted surveyor's tape (i.e. lead line) from the FRF pier deck (on a calm day) to the visually determined still-water level next to the gage. b. The distance from the bottom of the gage to the still-water level was determined by accounting for the distance from the top of the gage to the pier deck in the above measurement and taking the difference between that value and the gage length. c. The gage output value was determined as the average of the few- minute sample of gage measurement output while the weighted tape measurement was made. d. The lead-line-determined level and the measured gage output were then compared to determine the zero offset of the gage. 24. This procedure is believed to be accurate to no better than +10 cm; errors arise from estimating the still-water level and from movement, bending, and expansion of the surveyor's tape used in the lead-line measurement. This accuracy is not sufficient for the detection of water slopes across the surf zone, which may only amount to a few centimeters difference at the measurement locations. The gage zero drift or uncertainty is random (see Figure 3). 25. Although this variability seems artificial, precautions were taken in the analysis of the 20-minute data records when computing wave statistics (see Part IV). Waverider buoy gages 26. The Waverider buoys were manufactured by the Datawell Laboratory for Instrumentation, Haarlem, Netherlands. Each 0.7-m-diameter buoy floats on the water's surface and (a) measures the vertical acceleration produced by the passage of a wave, (b) doubly integrates this signal to produce a dis- placement signal, and (c) telemeters this signal to an onshore receiver and associated electronics which extract the displacement signal for data logging 20 Nearshore Baylor Gage No. 615 ==» 0 E = on =o ne T (=) ° ° ; If | 10 ° - 20 20 Pier End Baylor Gage No. 625 Zero Drift (cm) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Date During 1980 Figure 3. Amplifier zero drift during 1980 (arrows indicate when amplifiers were reset to 0.0 cm) and analysis. The manufacturer states that wave amplitudes are correct within 3 percent of their true value for frequencies between 0.065 and 0.5 Hz (iziexs, wave periods between 15 and 2 second). For frequencies as low as 0.03 Hz (i.e., for a 33-second period), the manufacturer provides a frequency response curve which must be used to maintain the 3 percent accuracy. The frequency response curve was not used for the data in this report since wave periods greater than 17 seconds were never observed. 27. Datawell recommends that Waverider buoys be cleaned and new batter- ies installed at least every 9 months. The buoys were replaced with cleaned, repainted, and calibrated buoys in October 1979 and August 1980. The buoys were calibrated at the Engineering Support Offices, Ocean Wave Instrument Facility, National Oceanic and Atmospheric Administration (NOAA) (Ribe 1981). Considerable biological growth occurs during the summer months when the water 15 temperature is above 10° C. At least one cleaning and painting with antifoul- ant paint during the summer reduces the fouling problem. 28. Ribe (1981) presents three correction factors to use to increase wave measurement accuracy. These factors are (a) the Datawell-specified de- crease in electronic sensitivity as a function of oscillation period, (b) a difference error based on deviations from (a) found during NOAA's calibra- tions, and (c) a temperature-dependent adjustment of the sensitivity due to an unknown chemical reaction in the conducting fluid surrounding the Waverider accelerometer. These corrections and their application are discussed below. 29. Datawell-predicted decrease in sensitivity (DW). Waverider buoy sensitivity /A/ for the buoy electronics decreases with increasing period T of sinusoidal vertical motion according to Datawell as follows: 2 /A/ = i (FE) : (1) where To = 30.8 seconds is a characteristics period provided by Datawell. This sensitivity decrease results in amplitude errors of less than 3 percent for oscillation (wave) periods less than 15 seconds. Figure 4 presents curves for (a) (DW) = /A/-1 , the Datawell-predicted sensitivity decrease error, and (b) the actual sensitivity decrease error obtained from predeployment buoy calibrations. Note the actual sensitivity does not follow the Datawell relationship (Equation 1) given above. 30. Difference error (d). Ribe (1981) presents a least-mean-squares second-order polynomial of the form shown below in period T_ for a "best- estimate" difference error d between the Datawell-predicted decrease in sensitivity and that found from the actual buoy calibrations: de ayia: (a, x T) + (a, x 17) (23 In Table 2, DW and d are tabulated as functions of T for each of the FRF buoys. 31. Temperature-related error. It was determined that for some un- known number of Waveriders the sensitivity was drifting downward, possibly since manufacture, and averaging about 1 percent per year. Sensitivity loss from some unknown chemical reaction was related to increases in electrical 16 Amplitude Error, Proportion 0.05 Dotowell Specification (DW) 70.02 r 8/1/80 Predeployment - 0.20 ) 5 10 15 20 25 a. Nearshore waverider (Gage no. 610) 0.05 Dotowell Specification (DW) -0.05 8/1/80 Predeployment -0.10 -0.15 -0.20 0) 5 10 15 20 25 b. Offshore waverider (Gage no. 620) 0.05 Dotowell Specification (DW) -0.05 8/1/80 Predeployment” -0.10 -0.15 -0.20 0 5 10 15 20 25 Period (s) c. Waverider (Gage no. 630) 6 km offshore Figure 4. Predeployment Waverider gage calibrations (after Ribe 1981) iby) Waverider Predeployment Calibration Informa Table 2 tion, 1 August 1980 Ne Gage No. 630 Difference Datawell Gage No. 610 Gage No. 620 Difference Datawell Difference Datawell Period Frequency d DW Period Frequency d DW Period Frequency 2.0006 4.50000 -0.4484 -G.0000 4.50000 89 -.0212 8. 2.0317 @.49219 -0.0485 -B.0000 8.49219 9 -G.G214 a. 210645 4.48498 -0.0487 -6,.0000 3.484 -5,0215 a. 2.0984 6.47656 -0.0488 -G,.G000 0.47656 -8.0217 a 211333 0.46875 -8.0489 -G.a000 g.46875 9-0. 62 2 8.468 211695 6.46094 -6,.0491 -6..000 8.46094 6.0220 2. 8.46094 2.2069 6.45313 -8.0492 8.45313 -8.6221 2. 6.45313 2.245 0.44531 -8.8494 6.44531 -8.0223 2. 6.44531 2.2857 4.43756 -8.0495 6.43756 -6.0225 2. 4.43756 2.3273 8.42969 -0.0497 8.42969 ‘-0,0227 2. 4.42969 2.3704 «= @. 42188 = -4.0499 8.42188 -.0229 2. H.42188 2.4151 B.41406 -6,0500 ; G.41406 9 -8.0231 2. 4.41406 2.4615 4.40625 -8.0582 5055 8.40625 -8.82 aaa 2.461 5.46625 21509e 6.39844 -8.0504 -8.9000 4.39844 9-0. 6235 -8,.0000 2.5098 6.39844 2.5606 4.39063 -8,. 0506 -0. 0005 0.39063 -8.0237 -6. 5000 2.5668 6.39863 2.6122 4.38281 -6, 6588 -6,0008 6.38281 -6.0240 -6.6008 2.6122 @.38281 2.6667 4.37500 -6,0516 -0, 66008 6.37500 -8,.9242 -6. 6006 2.6667 4.37568 2.7234 4.36719 -6,0512 -6, 0000 6.36719 -0.0244 -6.0000 2.7234 8.36719 2.7826 6.35938 -6.0514 -4,. 6060 6.35938 -6.6247 -6.00060 2.7826 6.35938 2.8444 6.35156 -6.0517 -6,9000 8.25156 -4,0256 -6. 0006 2.8444 8.35156 2.9091 8.34375 -8,0519 -6.0000 8.34375 -4, 0252 -6. 0006 2.9091 8.34375 2.9767 8.33594 -@.0522 -0.0006 6.33594 -9.0255 -6.0000 2.9767 = 33594 3.0476 6.32813 -8,0524 -6.0008 6.32813 -8.0258 -6.0000 3.0476 4.32813 3.1226 6.32031 -9.0527 -0.0681 8.32031 -4,0262 -0.0001 3.1226 6, 32831 3, 2008 6.31250 -6,0530 -8. 0001 0.31256 -8.6265 -6.0001 3.2606 6.31256 3.2821 6.30469 -6.8533 -6.0061 4.30469 -4.0263 3.2821 9.30469 3.3684 6.29688 -6,0536 -6.0881 6.29688 -6.0272 -6.061 3.3684 8.29688 3.4595 6.28906 -6.0539 -8. 0001 6.28906 -0.0276 -6,0001 3.455 5.28906 3.5556 6.28125 -3,.0543 -5.0001 6.28125 -4.0279 -6,.5001 3. 6.28125 3.6571 6.27344 -6.0546 -8.0661 6.27344 -4, 0284 -4.0061 3. 8.27344 3.7647 6.26563 -6,8550 -6,.0001 8.26563 -6.0288 -6, 9001 2 9.26563 3.8788 8.25781 -6,0554 -8. 001 6.25781 -6.0292 -6.0001 oe 9.25781 4.0006 6.25008 -6,0555 -8, 4061 a. 25000 -6.0297 -6.0001 4. 6.25000 411296 6.24219 -0.0562 -6.0002 G.24219 -6.0302 -0.6002 4.1298 8.24219 4.2667 0.23438 -8.0567 -6.a002 8.23438 -8.0308 -4.0002 4.2667 = 23438 4.4138 0.22656 -8.0572 -0,.0082 6.22656 -8.0313 -8.0002 4.4138 . 6.22656 4.5714 8.21875 -G.0577 -0.0002 O.21875 -8.0319 -B.0002 4.5714 8.21875 417407 8.21094 8.0582 «= -G. 8003 6.21094 §-0.0325 -0.0002 4.7407 8.21094 4.9231 6.20313 -0.0588 -0,.0003 6.20313 -0.0332 -0.0002 4.9231) (8.120313 5.1206 G.19531 -8,0594 -0.0004 6.19531 -6,0339 -6. 0004 5.1266 6.19531 5.3333 6.18750 -G.G6u1 -8, 0004 6.19750 -6,6346 -6.0004 5.3333 8.18750 5.5652 6.17969 -@.0607 -0.0005 6.17969 -@.0354 -8.0005 5.5652 8.17969 5.8182 @.17188 -8.0615 -0.4006 0.17188 -@.0363 -0.0006 5.8182 6.17188 6.0952 8.16406 -6.0623 -0.0003 G.16406 -8.0372 -0.8008 6.6952 6.16406 6.4006 0.15625 -8.0631 -0.0009 6.15625 -0.0381 Eosacas 6.4000 4.15625 6.7368 6.14844 -6.6646 -6.0011 6.14844 -8.0391 -6.0011 6.7368 6.14844 2.1111 8.14063 -6.0649 -6.0014 4.14063 -6.0402 -8.0014 iaeees! 8.14063 7.5294 8.139281 -0.0659 -G,0018 8.13281 -0.0414 -0.0018 7.5294 4.19281 8.0686 8.12568 -0.0670 -8. 8023 6.12500 ~8.0426 -.60 8.6056 6.12580 8.5333 6.11719 -8.6681 -4.4029 3 6.11719 0.0439 «= -B. 029 8.5333 G. 11719 9.1429 6.10938 = -0.0693 «= 0.6039 911429 8.10938 «= -8.0453 -0.0039 Bone eee 9.8462 0.10156 -8.0705 -6.0052 3.8462 8.16156 -8.0467 -G.0052 Ses ecm Ge1 0156 16.6667 8.09375 -0.0718 -6.0071 16.6667 «09375 -G18482 0-4. 0071 Honea oleae 11.6364 8.08594 0.07300 -. 100 1116364 8.08594 0.8496 0-0. 100 Se) RES 12,9000 © 8.07313 -G.0741 0 -G. B46 12.8006 6.07813 -6.0509 -6.6146 12.6088, B.B78l3 14.2222 0.07031 -6.6749 -a.0220 14.2222 0.07031 -@.0518 -0.0220 ig.ce2e §=60-67831 16.0000 0.06250 -G.0751 -0.0345 16.0006 6.06250 -@.0519 -0.0345 16.0808 0.06250 18,2857 8.05469 -G.6739 -G. 9569 18.2857 6.05469 -@.0506 -.a569 18,2057 8.65469 21.3333 @.94688 -0.0698 -d.0984 21,3333 6.04688 -@.0459 -@.09384 21.3333 6.64688 18 -. -0. =O 6. -6. -6. -4. -8.6 =H -6.6 Ole =O. -@.0129 -8,.G131 -8,6133 -6.6136 -§,.0138 -6.0141 -6.0143 -6.6146 -4.0149 -G.0152 -8. 6829 -6,0039 -0.9052 -6. 0871 -6.6106 -H.0146 -6.0220 -6.6345 -6. 6569 -6.6984 -6,.0331 ~6.0344 -8.6355 -§. 0366 -6.6372 -6,.0371 -G.0355 -6.6367 conductivity of the conductive fluid surrounding the accelerometer. This drift could be identified from calibrations over a succession of time. 32. In 1982 Datawell made available an improved modulator printed- circuit board for bringing calibrations within specification and for prevent- ing further decrease in sensitivity; however, this modification was not made for the 1980 FRF buoys. Datawell provided curves for correction of calibra- tion sensitivity based on differences between buoy temperature during calibra- tion and buoy temperature when the buoy is measuring waves in the ocean. The NOAA Engineering Support Office developed a table based on the Datawell curve which can be entered with the uncorrected difference error value d (Table 2) and the temperature of the water during the time of the buoy operation to determine the difference error correction (see tabulation below). The dif- ference error correction is added to 4d _ to obtain the corrected difference error D . For temperatures during buoy operation greater than the buoy tem- perature during calibration (22.4°C), no correction is necessary. Water Temperature (degree C) Diff. 22.4 20 13 16 14 12 16 s 8.00 @.060 6.601 6.001 8.001 0.861 6.000 -8.600 -8.062 -0.01 @.6060 6.007 6.008 6.609 8.016 6.611 6.611 0.611 -8.02 0.000 0.069 6.012 0.014 6.016 8.018 9.019 0.026 -0.63 0.600 6.609 G.013 @.016 08.819 8.621 6.624 0.626 -0.84 8.000 6.008 9.012 0.016 0.020 6.623 0.027 8.029 -8.05 6.000 6.066 0.011 0.016 6.620 6.624 0.628 6.832 -8.06 @.000 0.004 0.018 0.015 8.020 0.025 6.030 0.034 -0.67 0.000 ©.003 0.609 6.015 6.621 6.0626 0.631 6.636 -8.088 @.000 0.003 0.010 0.017 0.023 0.029 0.034 8.039 -8.69 0.000 0.006 0.013 0.019 8.626 6.032 0.638 6.643 -8.10 @.000 0.010 0.017 0.024 0.031 0.037 0.043 6.049 33. Since these error corrections are oscillation-period dependent, their application requires that the wave data be decomposed into amplitude coefficients or variance-spectrum coefficients for each frequency or period. A less accurate but also less complicated procedure would be to apply a single correction to, say, the significant wave height based on the peak spectral wave period and an average water temperature estimate. For correction of amplitudes or derived parameters linearly related to amplitude, a correction factor F(T) can be obtained from the sum of the Datawell DW and temperature-corrected difference error D by: 19 ey ears SOUS | Ieee (WA D) (3) which can be applied by multiplying the uncorrected amplitude by F(T) for T equal to the peak spectral wave period. For correction of parameters re- lated to the square of the amplitude (i.e., total energy or variance spectrum coefficients), the following should be used: 2 2 1 ft) “|7+ Dw + D) — 34. The following example demonstrates use of the calibration results. The nearshore Waverider buoy on 25 October recorded the annual extreme signif- icant wave height of 3.80 m with an associated peak spectral period of 10.9 seconds. From Table 2, the Datawell-predicted sensitivity error DW is -0.0071, with a corresponding uncorrected difference error d of -0.0718. 35. To determine the correction for the difference error, the water temperature is also required; the ocean water temperature at that time was approximately 16° C (see Part V). The correction (see tabulation) is 0.015, thus: Di= id t+.0.015 = -0.0718 +:0 015 or D =" =0.0568 F(T) can be determined from Equation 3 as ] BCD sie (DW + D) io 1 ~ 1 # (-0.0071 =" 0.0568) 0.9361 F(T) 1.0683 Finally, the corrected significant height is 3.80 m x F(T) = 3.80 m x 1.0683 = 4.06 m , which is a 7 percent increase. 36. In general, the wave statistics errors are near 5 percent for wave 20 periods less than 12 seconds (12 seconds is equal to the annual mean plus one standard deviation wave period). Errors of this magnitude are generally tolerable for most engineering applications, although it is worthwhile to know the error bounds for some design considerations. When investigating coastal phenomena involving very long period swells of 15 seconds or greater these corrections will produce significant increases in the magnitudes of the wave parameters and it is recommended that the corrections be used. Tide Gages 37. Water level data from the FRF pier are presented in this report. A NOAA/NOS control station, located at the seaward end of the research pier, consisted of a Leupold-Stevens gage manufactured by Leupold and Stevens, Inc., Beaverton, Oregon. The Leupold-Stevens analog-to-digital recorder was a float-activated, negator-spring, counterpoised instrument that mechanically converts the vertical motion of a float into a coded, punched paper tape record. The below-deck installation at pier station 19+60 (see Figure 2) consisted of a 30.5-cm-diameter stilling well with a 2.5-cm orifice and a 21.6-cm-diameter float. 38. The FRF tide gage was checked daily by a tide gage tender at the FRF for correctness of time, proper operation of the punch mechanism, and ac- curacy of water level information obtained. The accuracy was determined by comparing the gage level reading to a level read from a reference electric tape gage. Once a week, a heavy metal rod was lowered down the stilling well and through the orifice to ensure free flow of water into the well. During the summer months, when biological growth was most severe, divers inspected and cleaned the orifice opening as required. 39. Quarterly, a NOAA/NOS tide "party," which consisted of NOS person- nel familiar with the installation and equipment, performed a tide station in- spection and review. The tide gage was surveyed in from existing NOS control positions and the equipment checked and adjusted as needed; and NOS and FRF personnel reviewed procedures for tending the gage and handling the data. Any specific comments on the previous months of data were discussed to ensure data accuracy. 21 Meterological Instruments Anemometer 40. Winds were measured using a Weather Service Model F420C anemometer consisting of a cup rotor and spread-tail wind vane. Through mid-September, the anemometer was located 58 m behind the dune, with the cups 6.4 m above NGVD. In late September, the instrument was relocated to the top of the labo- ratory building at an elevation of 19.1 m (Figure 2). The accuracy of the speed transmitter and indicator assemblies was (a) 1 percent up to 100 m/sec and (b) 2 percent over 100 m/sec. The wind direction transmitter and indicator assemblies were accurate to +5 deg at an air speed of 0.26 m/s or greater. 41. In September, after installation on the laboratory roof, NOAA/ National Weather Service (NWS) personnel calibrated the speed cups and set the direction reference to true north. The speeds were found to be approximately 5 percent faster than actual, and the instrument was reset. The anemometer had been last calibrated in the spring of 1979 at which time, it is believed, the zero offset was incorrectly set; consequently, the data before September should be corrected by reducing the value indicated by 5 percent. 42. The wind speed and direction were recorded on a battery-powered Esterline-Angus recorder. Problems with the recorder's clock and tape advance mechanism and the pen actuator (for indicating direction) were frequently found, and the unit required day-to-day maintenance. 43. Maintenance of the anemometers consisted of troubleshooting the records and resetting the instrument based on the calibration results. Microbarograph 44. This recording instrument, an aneroid sensor used to measure atmo- spheric pressure, responded to pressure changes on the order of 0.169 mb. The microbarograph was manufactured by the Belfort Instrument Company, Baltimore, Maryland, and was located inside the office trailer, 6 m above NGVD, until June when it was moved inside the laboratory building, 9 m above NGVD (Figure 2). 45. Daily, the microbarograph was compared to an NWS aneroid barometer; adjustments, although infrequent, were made as necessary. The microbarograph required very little maintenance except that required to ink the pen and wind the clock every 3 days when the chart paper was changed. Maximum/minimum thermometers 46. NWS maximum and minimum thermometers were used to determine the 22 daily extreme temperatures. The thermometers were housed in an NWS instrument shelter located 91 m behind the dune (Figure 2). The shelter was designed with louvered sides, a double roof, and a slatted bottom for housing instru- ments requiring protection from direct sun. 47. The actual temperature readings at the time the thermometers were read (i.e., the present temperature) were compared to ensure accuracy of maxi- mum and minimum values. Maintenance consisted of periodic removal and clean- ing of the thermometers with soap and clean water and lubricating the support used to hold and reset the instruments. Rain gage 48. A 30-cm weighing rain gage manufactured by the Belfort Instrument Company, Baltimore, Maryland, used to measure the daily amount of precipita- tion, was located near the instrument shelter 87 m behind the dune (Figure 2). The manufacturer's specifications indicated that the instrument accuracy was +0.5 percent for precipitation amounts less than 15 cm and +1.0 percent for amounts above 15 cm. 49. A 15-cm-capacity "true check" clear plastic rain gage with a 0.025-cm resolution, manufactured by the Edwards Manufacturing Company, Albert Lea, Minnesota, was used to monitor the performance of the weighing rain gage. This gage, located near the weighing gage, was checked daily, and very few discrepancies were identified throughout the year. The weighing rain gage re~ quired little maintenance except to wind the clock and ink the pen. The pen mark on the chart records did "bleed" or drip down when a driving rain was directed at the access door. Sling psychrometer 50. A sling psychrometer was used to measure wet and dry bulb tempera- tures for determining relative humidity and dew point. The psychrometer had two thermometers mounted in a frame which was rotated rapidly. A moistened muslin wick was attached to the bulb (i.e. wet bulb) of one of the thermom- eters, and the device was whirled to ventilate both thermometers. The wet and dry bulb temperatures were read, and a set of NWS tables were used to deter- mine the dew point. 51. These thermometers required little maintenance except to change the muslin wick every month or two and to clean the sling and thermometers with soap and water. The instruments were not calibrated, but the thermometers were compared daily to detect any bias or malfunction. 23 Pyranograph 52. A mechanical pyranograph, manufactured by the Weather Measure Cor- poration, Sacramento, California, was located on the top of the weather in- strument’ shelter and provided a record of the duration and intensity of solar radiation. The pyranograph was not calibrated, but was observed to operate in a reasonable manner. This equipment required that the glass cover be cleaned, the chart paper changed every week, the timer wound, and the pen inked. 24 PART IV: DATA COLLECTION AND ANALYSIS 53. In this section, the FRF data acquisition system, data collection techniques, and data analysis procedures are discussed. Digital Wave Data Recorders/signal conditioning 54. The data acquisition system consisted of a primary and backup re- corder and associated electronics for signal conditioning prior to recording. Two different primary recorders were used to collect the wave data. Prior to October 1980, the primary system transmitted analog data signals via telephone lines from the FRF to Ft. Belvoir, Virginia, where the data were recorded in digital form on a Modcomp I1I/25 minicomputer. After October, a Data General NOVA-4 minicomputer located in the FRF laboratory building was used to collect the data. In addition, a backup system consisting of a Lockheed Store 7 (FM) recorder located at the FRF was used to record data when the primary system was known to be inoperative. Frequently during storm conditions the backup system was run simultaneously with the primary system to ensure that wave data were obtained. A second FM recorder located at CERC (Ft. Belvoir) was used to play these tapes into the Modcomp so that the data recorded could be digitized. 55. Regardless of the system used, the voltage signal from the sensors required certain conditioning. For the phoneline/Modcomp system, the signal was first amplified and biased to ensure a O- to 5-V range, then converted to a frequency-modulated (FM) signal by exciting a voltage-controlled oscillator (VCO). That signal was then transmitted to Ft. Belvoir via telephone line where a discriminator was used to convert it back to a voltage signal. This signal was fed into a demultiplexer and converted to a serial data stream which was then sampled by the Modcomp. For the NOVA-4 and FM recording sys- tems, the O- to 5-V signal was fed directly into the recorders. However, since the FM recorder operated on a maximum output of 3 V, it linearly scaled the 0= to S=V signal by ‘a factor of 3/5. Collection 56. The signal from the wave sensors was routinely sampled four times per second for 20 minutes every 6 hours beginning as near as possible to 0100, 5) 0700, 1300, and 1900 hours Eastern Standard Time (EST); these hours correspond to the times that the NWS creates daily synoptic weather maps. During storms, hourly data recordings were made. Since the Modcomp/phoneline and NOVA-4 sys- tems were automated, recording data during nonduty hours and on weekends and holidays created only a minimum of problems. Prior to October, the FM re- corder was run manually, and for most dates only two observations, one in the morning and one in the afternoon during duty hours, were obtained. In gen- eral, the FM recorder was not run on the weekends and holidays unless there was a particularly interesting event in progress, such as a storm or experi- ment. After October, a controller was used to turn the recorder on and off at specified times; this automation permitted FM data collection in the evening and on weekends. Data tapes 57. The wave data were recorded in digital form with the following basic tape format: two records of header information which include (a) the station identification number, (b) the date and time, and (c) a variable num- ber of records necessary to obtain 20 minutes of data from all sensors at a sample rate of four values per second. Each record contained 384 20-bit integer words (i.e., binary format); each integer word represented the com- puter units corresponding to the instantaneous voltage output of the sensor. The above sequence of records was repeated for each recording interval until the data tape was filled. Seven-track tapes were used for data recorded via the Modcomp computer, while nine-track tapes were used with the NOVA-4. (The 20-bit word size is unusual but necessary because CERC processed the data on a CDC 6600 machine with a 60-bit word size; when necessary, CERC converted the data tapes to an ASCII format). Analysis/summarization procedures 58. The CERC procedure for analyzing and summarizing digital wave data was based on a Fast Fourier Transform (FFT) spectral analysis procedure. The final results were also subjected to human editing and quality control before public distribution (Thompson 1977; Harris 1974). The computer analysis routine used 4096 data points (1024 seconds of data sampled four times per second) for each data record processed. The program first edited the digital data record, checking for nonnumeric characters, jumps, and spikes (i.e., deviations greater than 2.5 and 5 standard deviations from the mean, respec- tively). If more than five bad data points were found in a row or more than 2.5 percent of the digital values in a record were determined to be bad, the record was rejected as unsuitable for analysis; for a few bad data points, the routine linearly interpolated between the erroneous values. If the rec- ord was determined suitable for analysis, the distribution function of the sea surface elevations and first five moments were computed. The variance (second moment) and skewness (third moment) were checked to determine if full analysis of the data record was warranted. Records with very low variance values and excessively skewed distribution functions were not fully analyzed. 59. After it had been determined that the record justified full analy- sis, a cosine bell data window was applied to increase the resolution for the energy spectrum of the record (use of the data window is discussed by Harris (1974)). After application of the data window, the program computed the vari- ance spectrum (energy spectrum) using an FFT procedure. 60. Significant wave height and peak spectral (or significant) period provided a convenient way to characterize the wave conditions contained in the data record and were more conducive to statistical summarization than the more complete, but complex, description provided by the spectrum. 61. Although significant wave height is defined as the average height of the highest one-third of the waves in a record, experimental results and calculations based on the Rayleigh distribution function show that the sig- nificant height is approximately equal to four times the standard deviation of the wave record (U. S. Army Corps of Engineers, Coastal Engineering Re- search Center (CERC) 1977). The peak spectral wave period (also referred to as the significant or peak period) for each digital record is defined as that period associated with the maximum energy density in the spectrum (Thompson 1977) 62. After 1 month of data had been analyzed, the significant wave height and peak period values were segregated by gage and tabulated for visual edit- ing. The editor checked for such things as unreasonable distribution of the sea surface elevations; clipping of the crest or troughs; inconsistencies be- tween successive observations; large trends in the 17-minute, 4-second data record; and discontinuities in the data. After the data had been edited, monthly summaries of significant height and peak period were generated for inclusion in summary reports. 72h Water Level Data Collection 63. The water level information was obtained from an NOS tide gage, which produced a digital paper tape of instantaneous water levels sampled continuously at 6-minute intervals. At the end of each month, the paper tape was removed from the recorder and mailed to NOS in Rockville, Maryland, for analysis. Analysis 64. The digital paper tape records of tide heights taken every 6° min- utes were analyzed by the Tides Analysis Branch of NOS. A Mitron interpreter created a digital magnetic computer tape from the punch paper tape. This tape was then processed on a Univac 732 computer. First a listing of the instanta- neous tidal height values was obtained for manual checking. If errors were encountered, a computer program was used to fill in or recreate bad or missing data, using correct values from the nearest tide station and accounting for known time lags and elevation anomalies. The data were plotted and a new listing was generated and rechecked. When the validity of the data had been confirmed, monthly tabulations of daily highs and lows, hourly heights (in- stantaneous height selected on the hour), and various extreme and/or mean water level statistics were generated. The mean sea level (msl) reported is the average of the hourly heights throughout the month, while the mean tide level (mtl) is midway between mean high water (mhw) and mean low water (mlw). Weather and Visual Observations Meteorological data collection 65. Each instrument used for monitoring the meteorological conditions at the FRF was read and inspected daily. For those instruments with analog chart recording capabilities, (a) the pen was zeroed (where applicable), (b) the chart time checked and corrected, if necessary, (c) a daily reading marked on the chart for reference, (d) the starting and ending chart times recorded, as necessary, and (e) new charts installed when needed. Sample chart records for the microbarograph (atmospheric pressure), rain gage, and pyranograph (solar radiation) are presented in Figure 5. The daily reading was recorded for all instruments except the pyranograph. Concurrent with the 28 eee, ON tN htt 14 Nov 1980 (On) 3h E518 Nov 1980 ( Off) tee S=cG=e SSPESEET SSeepesease aba = == = aS — i —" ear! mie = Sak Sass 3 6 o9 2 fey 18 ray 00 03 06 oO 12 is 18 2 00 03 06 09 12 is 18 a 00 03 06 oo 12 ir y 18 21 00 03 06 O98 12 a. Microbarograph 1UNOAY won 40 oom7 4 oe oiomt2 4 wom 74 bane : Tee FEEECeEeE=21 Jul 1980 (On) =ceck ie a5 pSEEEEeeeer 29 Jul 1980 (Off phy Pag hn ys 16 [20 [ur fa’ [oe A HEL TATA EEF EPEF FETT, zee BEPEPL EERE: ige2ee2s5Se25 HAE BHT AH Utena : IEE} gpa 58596555) ELF EPEEFE ET | HHA BEE LT EEEEET EEE Fiz : ESSE E REEL FES HEE EEL HH une REE EEA ACH Recaa? pacndeaene FERAL EEL EE HH aoe, fesee eee Nee EEEEC CET FR MEET EEEr AM AW ENED ANE cat BUEGaEEEE aN tang Mi Bades:A0auuay ée eh CGGGuy ANGBNA VGEUG/ QUFNnd \euuar dual.l.ssoce6 (2 Agua CENGe”NEBBALe DAILY SUMMARY = ht at ua rl as | = et c. Pyranograph Figure 5. Sample chart records for the microbarograph, rain gage, and pyranograph instrument readings, weather information such as cloud cover, visibility, and predominant weather conditions were visually obtained. 66. The monthly meteorological data tables in Appendix A were prepared from single daily observations made near 0700 EST and thus do not represent daily or hourly averages; therefore, caution should be exercised when inter- preting the results. 67. The wind information provided in this report, excluding that found in the tables of Appendix A, was based on wind speed and direction values de- termined every 6 hours from the instrument chart records and represents esti- mated average values based on 10 minutes of record. Meteorological data analysis 68. Wind roses were computed for the wind speed and direction values obtained every 6 hours. The directions were specified at 22.5-deg intervals; i.e., a 16-compass-point-direction specification. Frequency distributions of wind speed for each direction were computed for the entire year, each 3-month season, and monthly. In addition to the wind roses, resultant directions and speeds were determined by vectorally adding each observation. 69. Dew point values reported herein were determined from psychrom- eter readings by computing the wet bulb temperature depression (dry bulb minus wet bulb) and using Table 19 in Appendix III of "Weather Service Observ- ing Handbook No. 1--Marine Surface Observations" (National Oceanic and Atmo- spheric Administration, National Weather Service 1974). 70. The atmospheric pressure trend is a number which specifies the manner and amount of pressure change occurring over a 3-hour interval before the pressure reading is made. The first number of the three-digit code repre- sents the characteristics of the change and was determined by comparing the barograph record to Table 17, Appendix III, of the Weather Service Observing Handbook. The last two digits of the pressure trends are a code which indi- cates the magnitude of the change and was determined from Table 18, Appen- dix III, of the NWS Handbook. Visual data collection 71. At the FRF, daily visual observations made near 0700 hours and con- forming to CERC's Littoral Environmental Observation (LEO) Program (Schneider 1981) were obtained to supplement instrumented data collection. These in- cluded observations of surface current speed and direction and wave-approach angle at the seaward end of the FRF pier. 30 Bathymetric and Pier Surveys Collection 72. In October of 1980, an FRF bathymetric survey was performed by Langley and McDonald, Inc. of Virginia Beach, Virginia, which covered the beach, nearshore, and offshore area. Each survey range extended seaward from the baseline behind the dune sometimes as far as 3200 m offshore, and ranges were located up to 4 km north and south of the pier. Control consisted of a series of monuments installed by CERC and the U. S. Army Engineer District, Wilmington (SAW), which were resurveyed by Langley and McDonald, Inc. The survey techniques used were as follows. 73. Beach surveying. Conventional level and tape techniques (Czerniak 1972) were used for the beach portion of the survey, with accurate results conforming to these specifications: an Horizontal) accuracy 4:15 sem. ba)! Vertical accuracy '2/0zSiyem. The beach portion of the survey extended from the monument baseline behind the dune to the maximum wading depth, approximately -0.5 m msl. 74. Nearshore surveys. The contractor used a sea sled with a stadia rod mounted on it to conduct surveys through the surf zone. The sled was pulled offshore by a boat and then winched to shore by means of a cable marked every 6.1 m. Each time a mark came to the winch (as the sled was winched in), the rod elevation was read from the beach by means of a level. 75. Offshore surveying. The contractor surveyed offshore by means of an analog fathometer mounted on a boat and two people on shore who triangulated the boat's position. The fathometer was calibrated on each range line by com- paring its measurement to the sea sled value at the sea sled's most seaward position. The angle and depth information was correlated and manually reduced to produce position and depth data. No correction for wave effects was made by the contractor. 76. Pier soundings. Weekly soundings along both sides of the FRF pier were performed. The lead-line surveying technique consisted of lowering a weighted measuring tape and noting the distance below the pier deck. Posi- tions between the pier bents (i.e., every 12.2 m) were used to minimize in- accuracies due to scour near the pilings. 77. Analysis. The pier, beach, nearshore, and offshore data were Sil reduced to position (X,Y) and depth (Z) triplets relative to the local NGVD. The data were listed, and a display of the profiles (i.e., distance along the range versus elevation) using line printer graphics was generated for visual inspection. After the data had been edited and determined to be acceptable, another set of routines was used to compute various statistics (i.e., maximum and minimum sand elevations) and displays (i.e., graphic profile representa- tions, envelopes of elevations, and time sequences of elevations), as in Appendix C. 78. The offshore portion of the October bathymetric survey showed an "artificial" rhythmical bending of the bottom contours. Errors in the off- shore portion are believed to have been the result of (a) using a floating surveying platform, (b) not performing a bar check calibration of the fathom- eter (i.e., calibrating at various depths and positions along the range), and (c) not accounting for wave motion in the fathometer data. At greater depths, stratification of the water temperature, water density, and thermoclines would have affected the accuracy of the measurements. Because of the low slope in the offshore region, small errors in elevation resulted in significant excurs- ions of the contours. Although the fathometer depth data seaward of the pier end are believed accurate to t0.2 m, caution should be exercised when the data are used. Photography Aerial 79. Quarterly aerial photographic missions were performed by a contrac- tor as part of the measurement program using a 9-in. negative format mapping aerial camera capable of black and white and color photography. All coverage was at least 55 percent overlap, with all flights flown as close as possible to periods of low tide and between 1000 and 1400 hours with less than 10 per- cent cloud cover. 80. The flight lines were concentrated near the FRF although one flight line extended from Cape Henry, Virginia, to Cape Hatteras, North Carolina. The flight lines and scale specifications are shown in Figure 6. 81. As part of the visual observations, daily color slides of the beach were taken using a 35-mm camera from the pier looking north and south. The 32 RUOEE INLET Flight Line 1 1: 12,000 Flight Line 2 1: 6,000 Flight Line 3. 1: 12,000 HATTERAS FIELD RESEARCH FACILITY Figure 6. Quarterly aerial photography flight lines, 1980 33 location from which each picture was taken, date, time, and a brief descrip- tion of the picture were marked on the slides, and an inventory was maintained. Analysis 82. There is no routine analysis of the photographic data except to inventory what is available. Sediment Data Collection 83. Data collection consisted of weekly samples of the surface layer (top centimeter) of sand taken by hand from the foreshore near the upper swash limit. In addition to the above, during July through November daily foreshore samples were taken. The data were obtained from the same location approxi- mately 500 m north of the FRF pier. Analysis 84. The sediment samples were analyzed with a rapid sediment analyzer to determine the size distribution of the sample (Duane and Meisburger 1969). 34 PART V: DATA AVATLABILITY/RESULTS Data Availability 85. Table 3 is intended as a quick reference guide to show the dates for which various types of data are available. Wave and tide gage histories and other status information which may explain major gaps in the data are provided in the respective results sections and in the appendices. Results 86. This part provides results of the weather, wave, tidal, water char- acteristics, survey, photography, and sediment measurements made during the year. Although this report is intended to provide basic data for analysis by users, many of the daily observations have been summarized by month, season, or year to aid in interpretation. If individual data are required where sum- maries appear, the user can obtain the detailed information by following the procedures described in paragraphs 6 and 7. Meteorological data 87. In this section, results of air temperature, precipitation, and wind speed and direction measurements are presented and discussed. Daily values are tabulated in Appendix A. 88. Air temperature. Air temperature measurements are summarized herein by describing the tendencies of the daily highest and lowest tempera- tures. Daily average temperatures were not computed since only one observa- tion of the "present" was obtained in the morning, which could be misleading. Temperature distribution during 1980 was similar to past years of measurements. 89. Figure 7 and Table 4 present the monthly average and extreme high and low temperatures. The warmest months were July, August, and September, when the average high and low temperatures varied between 21° and 30° C. The highest temperature recorded in 1980 was 37° C on 2 August; the 1979 high was 43° C in July. The lowest temperature measured at the FRF to date, -11° C, was observed on the 18th of February 1980. February continued to be the coldest month with the smallest difference between the average daily high of 3° C and low of -2° C. The widest range of temperatures occurred during the cold months, January through March, November, and December, with February 35 a Vivd 40 434M 11NA G3ANIVLdO0 VLVG | | dO SAVG 2 NVHL SS31 vivaon [] QN35931 SESS ES <8Shh sashes ese aS sashes eee eee eee 4444 AB Re x Bakes Eas 44444 EES VV |_| Baek 44440 44448 4 | 4 ; MAAhAhsAsasssds yt tan oe Bsegpeetes snsbscets Ce a VVV| su0ns310 4 & onan 456 SQSHSEB 2S 0200S Gcee dese Rs EOE Ree HdVYOONVWYAd AJOVONIVY Nve HLNOW 433M JO AVG 1Sdid AVITTGeTLeay e1eq O86L € eTqeL 36 40 . 1980 X xX xX oa 0 x om x : coo u6elCUtll CC® i) —) o + + 0 _ 0 oO (0) 2 10 oO ny + + ® QO Qa + = | a Y oO o 0 or + Extreme High X be ra + Mean High 0 + —q -10 Mean Low Oo + Extreme Low + Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month Figure 7. Monthly high and low air temperatures, 1980 Table 4 Meteorological Data Summary for 1980 Wind of Number Resultant Extreme Temperature, °C Precip- Average of Direction Direction High Low itation Speed Obser- Speed (deg from Speed (deg from Month Average Extreme Date Average Extreme Date mm m/sec vations m/sec true N) m/sec true N) Date Jan 9 20 12 3 =) 31 89 5.8 aK Ga Se 356 10.8 203 llth 23 13th Feb 3 19 23 =P cla 18 66 5.6 103 2.4 337 eS 338 10th 29th Mar 12 23 Pes 4 =i; 3 89 Gel 121 eG 334 20.6 23 2nd Apr 20 29 26 11 3 2 112 4.9 82 1.0 241 HS} 203 10th 248 15th May 24 34 25 15 9 3 39 4.4 77 0.8 219 8.2 23 8th 45 26th Jun 27 34 30 18 11 21 60 5155 93 0.8 210 12.4 248 7th Jul 30 34 21 21 16 25 64 4.0 113 1.4 2177, 8.2 248 3rd Aug 30 37 2 21 15 25) 48 4.5 96 (Ar/ 284 8.2 723} 22nd Sep 29 34 3} 21 11 12 30 4.0 95 0.8 183 Ue? 248 3rd 23rd Oct 21 27 11 13 5 27 73 5.4 113 0.7 323 14.9 248 25th 14 Nov 16 23) 5 7 =3 20 96 5.8 114 1.9 317 129) 23) 16th 10 Dec 12 20 9 3 Cal 29 47 6.2 111 Peine) 358 14.9 0 25th Annual 19 37 Aug 11 = Feb 7A33) Die. 1229 1.0 323 20.6 23) Mar 37 showing a 30° C variation. On the other hand, during January and February, the average high and low temperatures were most nearly the same, showing only a 5° to 6° C difference. These tendencies reflect the complex interaction of (a) sea temperature, which varies slowly; (b) wind direction, which can change very quickly; and (c) winter air systems, which can come from the Arctic air masses to the north or from the tropical maritime air mass to the south. The opposite is true during the warm months of June through September when the temperature variation was 23° C (versus 30° C in February) and the average highs and lows varied by as much as 9° C in July, compared with 5° to 6° C in January and February. 90. Precipitation (See Table 4). A total of 793 mm of precipitation was measured during 1980, 400 mm less than during 1979. Table 5 shows the monthly means, maxima, and minima from 1978 through 1980 at the FRF; absent during 1980 were monthly rainfalls in excess of 125 mm, as occurred in 1979 during January (180), May (239), and September (160), and in 1978 during March (137), May (145), June (130), and November (130). April was the wettest month of 1980, with 112 mm of rain measured; September was the driest month, with 30 mm of rainfall. 1980 totals were the lowest in 7 of the months and the highest in 3 others. Table 5 Monthly Precipitation Means, Maxima, and Minima at the FRF from 1978 Through 1980 Monthly Maxima Minima Mean Month mm Year mm Year 1978-80 Jan 180 1979 89 1980 135 Feb 94 1979 66 1980 80 Mar S}7) 1978 64 1979 97 Apr iy 1980 Hal 1979 86 May 239 1979 39 1980 141 Jun 130 1978 60 1980 87 Jul 104 1978 64 1980 79 Aug 48 1979 36 1978 44 and 1980 Sep 160 1979 13) 1978 68 Oct 73 1980 25 1978 5 Nov 130 1978 96 1980 108 Dec 84 1978 47 1980 60 38 91. Winds. Since the wind speed and direction data for 1980 were ob- tained every 6 hours (i.e., four times per day), the summaries are believed to be far superior to those previously published, which were based on only one daily value. No attempt will be made to compare the data summaries to prior years except for a brief explanation of why the data are believed to be more representative and less biased. 92. Land-sea breeze, weather fronts, and cyclonic and anticyclonic pressure systems all can cause rapid changes in both the wind speed and direction. 93. During March through September, the air temperatures were warmer than the seawater; likewise, from January to February and October to December, the air temperatures were colder. These temperature differences, along with differences in land temperature, can create daily coastal breezes which vary direction from morning to evening. Passage of weather systems can also cause the wind direction to change. Figure 8 shows all occasions during 1980 when the measured wind direction changed from offshore to onshore or vice-versa be- tween 0700-1300, 1300-1900, and 1900-0100 hours. Onshore implies an easterly component of direction, while offshore is westerly; half arrows indicate the shift was either from or toward a direction without an easterly/westerly com- ponent; i.e., north or south. 94. Figure 8 shows the following tendencies in wind direction changes for 1980: (a) during the morning hours 0700-1300, when, typically, heating occurs after sunrise, the wind directions change from offshore/westerly to onshore/easterly; (b) conversely, in the evening from 1900-0100, during cool- ing times after sunset, wind directions shift from onshore to offshore; (c) wind direction changes during the afternoon hours from 1300 to 1900 appear mixed but show some correlation with the temperature differences between the ocean and the air/land (see Figure 24 and paragraph 124). 95. Measurements made once a day would be incomplete and would produce significantly biased information. As noted in the data analysis section, all wind information summaries except for the meteorological tables in Appendix A were created from observations made every 6 hours. 96. Measurements made every 6 hours, however, have the following shortcomings: peak conditions can be missed; precise times when fronts pass can only be bracketed; correlation to other physical phenomena, such as the rise and fall of the tides, can be difficult; etc. Hourly meteorological 39 (sainoy 9 AtoAad opeu SUOT}JEATISGO) O86 ‘asUeYD UOTIIIATP pUTM Jo SawTy *g asan3Ty 40USHO ¥ BJOUSUO 4 puaba "RAH ot poe W Tat dW hay oA owe ON OW fF etd an are Ww yt 4h 1 o9¢ OSE Obe}OCe Oet OIF Ak a) 2 | CS OY | OOE O62 O82 {O22 092 OS2 |Obe O£2 O22} 012 O02 O6I {08! OL! 091 JOS! Hh Op! v oc! Bey) Le a A uo ot yt tt Whe 4 Fb AR 4] Gis ons _= ¥O sunoy tH aAAyo OP AEE MAY gpPt | 157.5° 202.5° 160.0° Resultant speed: 1,9 m/s Direction: 317° Figure 11. AUG 1980 337,5° 90° ° 315.0° “EHD 67.5° 292.5° 4. Pod [| Ss = ° 90.0 270.0° a a, l Vy 112.5° ° 225.0° ae 202.5° 160.0° Resultant speed: 0.7 m/s Direction: 284° OCT 1980 337.5° 0.0° 22.5° ° 315.0° gos0 4 67.5° 292.5° a& [— } o 90.0° 270.0° ? 247.5° 1 « 112.5° 13.0° 157.5° 180.0° Resultant speed: 0.7 m/s Direction: 323° DEC 1980 337.5° 315.0° 45.0° 67.5° 202.5° aS Fg & = sane Ss CT] 90.0° ey o 225.0° 202.5° 160.0° Resultant speed: 3.3 m/s Direction: 358° Wind Speed (m/sec) Se 0 5S 10 15 20 25 30 35 40 Frequency (percent) (Concluded) JAN-MAR 1980 46 APR-JUN 1980 ° 3a7.5° 9-0° 337.5° 00 22.5° ° ° 315.0° 45.0 mista’ 45.0 67.5° 67.5 292.5° ay W oe 292.5° As /, FS iy ea oe cul ° ae 90.0° 90.0 ca Jo 270.0° P 270.0° p L~) —R 2 247.5° ¢/ o\ 112.5° ae 1 Y 112.5° 225.0° 135.0° 225.0° 1%.0° 157.5° 157.5° 22.5° 160.0° 202.5° 160.0° Resultant speed: 2.2 m/s Resultant speed: 0.8 m/s Direction: 344° Direction: 224 JUL-SEP 1980 OCT-DEC 1980 aeyige MULU gags 337.s° 90° 32.50 315.0° 45.0° moe 45.0° iT 67.5° 67.5° 292.5° © 2 292.5° © w® rs & Re, os 90.0° d 30.0° 270.0° a 270.0° =! —, ay S 0 ba 5 l \ 112,5° 247. 0 v 112.5 ane 135.0° sage 135.0° 157.5° 157.5° 202.5° 180.0° 202.5° 160.0° Resultant speed: 0.8 m/s Resultant speed: 1.8 m/s Direction: 221° Direction: 340° Wind Speed (m/sec) © 2 WV S eA iio wo 9 10) 5 10 15 20 25 30 35 40 Frequency (percent) Figure 12. 1980 seasonal wind roses for the FRF, reference true north 100. Although no tropical cyclones of hurricane strength made landfall along the North Carolina coast during 1980, Hurricane Charley in August and Hurricane George in September passed close enough to the FRF to influence the wave conditions (see Figure 13). Hurricane Charley caused moderate waves in excess of 1.5 m at the seaward end of the pier on 21 August while still in the subtropical storm stage before intensifying and moving east well offshore. Remnant 1l-m-swell waves with associated 12- to 15-second periods were evident during the first few days of September as Hurricane George moved north more than 600 km offshore. 101. 1980 was a typical year with respect to the winds at the FRF. Seasonal variation (see Figure 14) from southerly in the warm months to nor- therly in the cold with an overall western dominance was expected. The North Carolina coast above Cape Hatteras did not experience the extreme winds asso- ciated with the landfall of a hurricane, but was battered numerous times by strong northeasters. Figure 13. Tracks of 1980 hurricane storms affecting the FRF 47 Wave data Figure 14. 180° s Annual and seasonal resultant wind speed and direction for the FRF, 1980 102. This section presents summaries from five wave sensors operated during 1980. The annual and seasonal significant wave height and peak spec- tral period statistics given below show a temporal and spatial variability of the wave climate at the FRF. and selected statistical summaries for each gage. Additionally, Appendix B contains gage histories 103. The 1980 data summaries are more complete than those for 1978 and 1979 (see Miller 1982); consequently, more confidence can be placed in the trends which are shown. 104. The wave height statistics (see tabulation below) vary as a func- tion of gage installation: significant wave height. Average Annual Distance from Water Gage Shore, m Depth, m Nags Head-112 200 Dj. Nearshore Baylor-615 100 1b) Pier End Baylor-625 500 8.4 Nearshore Waverider-610 600 7 Offshore Waverider-620 3000 18 48 Significant Height, m (Standard Deviation) For example, the offshore Waverider buoy (gage as water depth increases, so does average annual Peak Period, sec (Standard Deviation) 0.87 (0.44) 0.66 (0.32) 0.87 (0.44) 0.99 (0.63) 1.06 (0.64) 9.00 8.79 9.00 eal? 8.56 (2.81) (3.45) (2.81) (2.81) (2.83) No. 620) is moored 3 km from shore where the water depth is 18 m; the annual mean significant wave height was 1.06 m, with a 0.64-m standard deviation. The nearshore Baylor gage (gage No. 615), located approximately 100 m from shore in 1.5 m of water, had an annual average significant wave height of 0.66 m, with a 0.32-m standard deviation. 105. Individual data observations show a similar correlation between wave heights and depth; this correlation agrees with the trends of Vincent (1981) whose method for obtaining the maximum energy one could expect in a wind wave sea as a function of the water depth predicts the variation with depth. 106. Figure 15 presents the annual cumulative distribution of signifi- cant wave heights for the FRF gages for 1980. In general, the probability of high waves increases with water depth at the gage installation. The nearshore Baylor was in very shallow water inside the breaker zone, even during moderate to low wave conditions; consequently, these statistics represent a lower energy wave climate frequently due to waves breaking seaward of the gage. 107. Figure 16 is a histogram of the peak period distributions. Pe- riods during highest wave conditions varied from 5 to 12 seconds depending on the distance the wave-generating area was from the pier; i.e., storms far off- shore, say 500 km or more, would tend to produce near 12-second wave periods, while more local storms would produce lower periods. Based on the occurrence of periods greater than 10 seconds, swell from very distant generating areas may have accounted for approximately 20 percent of the conditions at the coast. Seasonal, annual, and historic-height-versus-period distributions are presented in Appendix B. 108. Tables 6 and 7 present seasonal average significant height and peak period values, respectively. The highest waves occurred during January through March, while the lowest occurred during the summer (July-September). From October through December and from January through March, the greatest variety of wave conditions occurred, as reflected in the high standard devia- tions. During January through March, longer average peak periods occurred as compared to April through June when short-period waves dominated. 109. Wave roses generated for 1980 (see Figure 17) were based on visual measurements of the direction at which the primary wave train (i.e., the wave train having the largest heights) approached; these measurements were made daily (near 0700) at the seaward end of the FRF pier. Wave height was determined from the pier end Baylor staff gage at a corresponding time. The 49 HEIGHT (METERS) Frequency (%) °o LEGEND N No. Observations o ouseeseue Gage No. 610 707 Tea FARO any aids SE Tenn es AEN Ria TI ORS AUPE RRA UNCON YASAD Ie oll ICi Gage No. 615 870 —-— _ Gage No. 620 808 Go Gage No. 625 906 n ‘i —xX— Gage No. 112 784 (=) Se Oo re [=] “i ~ ° SH oO 3 | =i oO t 2 10 10 10 10 PERCENT GREATER THAN INDICATED Figure 15. 1980 annual wave height distributions No. Obsns. Gage No. Gage Name A 808 oO - 620 Offshore Waverider 707 + - 610 Nearshore Waverider 906 po —- 625 Pier-End Baylor (Bars) 870 18] - 615 Nearshore Baylor 784 Ay S82 Nags Head Period (s) Figure 16. 1980 annual wave period distributions 50 Table 6 Seasonal Significant Wave Height Statistics for 1980 No. No. No. No. Gage No. Jan-Mar Obs Apr-Jun Obs Jul-Sep Obs Oct-Dec Obs 620 Height (m) aay) 184 0.85 162 0.72 151 1.14 Sik: Standard deviation (m) 0.65 0.34 0.33 0.75 610 Height (m) P45 129 O27 2 172 Os71 76 102 330 Standard (None deviation (m) Oni 0.33 0.30 for 0.64 July) 625 Height (m) 121 203 0.69 218 0.63 170 107) 315 Standard deviation (m) 0.62 0.30 0.28 0.58 615 Height (m) 0.93 149 0.56 216 0.53 168 0.67 337] Standard deviation (m) 0.45 0.20 0.17 0.30 2 ~ Height 1.09 206 = 0.70 204 0.70 165 0.98 209 Standard (None deviation (m) 0.42 0.30 0.33 0.51 for Dec) Table 7 Seasonal Peak Wave Period Statistics for 1980 No. No. No. No. Gage No. Jan-Mar Obs Apr-Jun Obs Jul-Sep Obs Oct-Dec Obs 620 Period (sec) 9.30 184 8.12 162 8.71 151 0.27 311 Standard deviation (sec) 3.08 2253 QT. 2D 610 Period (sec) 10.08 129 8.79 ye 9.32 76 8.99 330 Standard (None deviation (sec) 2.56 2.60 2.39 for 3.00 July) 625 Period (m) 9.54 203 8.73 218 9.35 170 9.08 315 Standard deviation (sec) 3.05 2.49 2.97 2.95 615 ? Period (sec) 9.14 149 8.49 216 8.70 168 8.88 337 Standard deviation (sec) 3435 S22 3.56 3.56 112 ~ Period 9.37 206 8.50 204 9.15 165 9.00 209 Standard (None deviation (sec) 2.96 2.82 2.65 2.71 for Dec) ANNUAL 1980 N 20.0° 42.5° | 65.0° 83.0° Resultant Wave Height: 0.5m | FRF Direction: 77° (57° TRUE) PIER Reference: Beach orientation 94.0° at 0°-180° Pier at 90° y SN 110.0° Pasa A Wave Height (m) 132.5° © Po Oe °° rd oo" > Ee Cr Gg sie 155.0° 0 10 20 30 40 50 60 70 80 Frequency (percent) a. 1980 overall wave rose 120° b. Resultant wave magnitude and directions Figure 17. Directional wave summaries for 1980 32 angles are relative to the pier at 90° and the beach oriented from 0° to 180°. 110. Wave heights approached the beach most frequently (50 percent) from the north side of the pier, 5 percent were shore normal, and 45 percent came from the south side of the pier (Figure 17a). Although accounting for less than 2 percent, waves in excess of 2 m approached from angles greater than 60 deg north of the pier axis. The angles shown represent the frequency of wave occurrence in 22.5-deg intervals, 11.25 deg on both sides of the angle displayed; except for the interval which includes the pier, which is split into angles greater than 76.25 deg and less than or equal to 90.0 deg; i.e., includes the shore-normal directions and angles greater than 90.0 deg but less than or equal to 98.75 deg. 111. The resultant magnitude and direction of wave approach for the year was 0.5 m from an angle 13 deg north of the pier axis, respectively, as shown in Figure 17b. Figure 17b also indicates the seasonality of the wave climate: waves during the cold months of January through March and October through December showed a northeastern tendency, while during April through September the waves approached more nearly shore-normal or from south of the pier. 112. The seasonal wave roses presented in Figure 18 indicate there was a strong northeastern tendency during January through March. During the pe- riod from April through June, somewhat of a transition period, waves approached slightly more often from south of the pier, while waves in July through Sep- tember had a strong southerly tendency. Waves during October through December showed the greatest tendency for approaching from the northeastern directions. 113. The tendency for waves to approach from north or south of the pier was very well correlated to the variation in the tendency for northern or southern winds (see paragraphs 91-101). 114. Although no hurricane severely affected the FRF, high wave condi- tions associated with "northeaster" storms occurred regularly during the cold months. On 16 occasions, the significant wave height exceeded 2 m at the sea- ward end of the pier, 25 percent of which persisted for 3 or more days (see the persistence tables in Appendix B). Three storms were particularly severe and accounted for the extreme significant wave heights measured at each gage location. First, on 3 March, a low pressure system located off the Virginia- North Carolina coast produced persistent onshore winds and high waves (see Figure 9); the high water levels produced significant wave heights He in 23 JAN-MAR 1980 28, aot 94.0 155.0° Resultant wave height: 0.7 m Direction: 72° JUL-SEP 1980 155.0° Resultant wave height: 0.3m Direction: 95° APR-JUN 1980 20.0° 42.5° 65.0° a, i 83.0° Se ~ 132.5° 110.0° % 155.0° Resultant wave height: 0.4 m Direction: 90 OCT-DEC 1980 20.0° 42.5° M > oe Ps 94.0° ~ 110.0° 155.0° Resultant wave height: 0.8m Direction: 66 Wave Height (m) 0 10 20 30 40 50 60 70 80 Frequency (percent) Figure 18. Seasonal wave roses for the seaward end of FRF pier, reference beach 0 to 180 deg excess of 2.3 m at the nearshore Baylor location. On October 25th, peak condi- tions of H. = 3.5 m were experienced at the pier end Baylor; this resulted from a northeaster coincident with a local perigean spring tide (see Miller et al. 1980). The last storm of 1980 on 29 December produced significant wave heights in excess of 2.9 m at the pier-end Baylor location (Miller et al. 1980). Tidal data 115. This section presents the FRF tide and water level data. The var- ious tide height values and water level datums due to predominantly astronomi- cal forces of the sun and moon are discussed, followed by discussions of the extreme high- and low-water levels which were particularly influenced by meteorological conditions. 116. Monthly and annual tide statistics are shown in Table 8, with 1979 annual average and extremes included at the bottom for comparison. Tides at the FRF are semidiurnal, and the average tide range for the year was 102 cm. The average of all tide hights (msl) during the year, was 8 cm above NGVD. Mean higher high water (mhhw), the highest of the two daily high tide tide levels, was 68 cm and exceeded the mhw value by 9 cm; mlw was -43 cm, and mean lower low water (mllw) was -47 cm for the year. (All tide values unless otherwise specified are referenced NGVD). The annual tide statistics for 1980 were very nearly the same as those for 1979. 117. Mean and extreme tide levels are presented as a function of month in Figure 19. The 5- to 6-month periodicity in the rise and fall of the mean values presented are due in part to the inclination of the sun, a long-period astronomical tide constituent commonly referred to as Ssa , which has a pe- riodicity of approximately 6 months. An additional explanation for the pe- riodicity observed may be (a) astronomical forces with annual periodicity and (b) seasonal oscillation of the specific volume of the seawater as a function of temperature, called the steric effect (see Pattullo et al. 1955). The distribution of all hourly heights is presented relative to NGVD in Fig- ure 20. Since the 1980 local MSL is 8 cm above NGVD, one can see that nega- tive departures from the mean are larger than positive departures. Harris (1981) indicates it is not unusual for the magnitude of positive and negative departures from the mean to be unequal. 118. Figure 21 shows the distribution of the daily highest and lowest tide levels which occurred throughout the year. On 87 occasions, or 1 percent 55 y3ty awerzxe = ya fa8uer uesw = JW $19}eM MOT MOT UeOU = “LOYEM MOL VW9IQxad = [29 pue fusqem ATTW {19},e4 MOT UROW = ATW STaAaT eas ueow = TSU $[aAeT aptz ueow = [QW ‘$21a}eM YSTY UeoW = MYW ‘193eM YSTY YsTY UeoW = MYYW :suUOTJeTAaIQGGe Jo uOoTJeURTdxXY » das T° S6- q°d L°O¢T 0°OOT 9° €4- 0-67- T°6 S°3 0°09 6°89 6ZL6L rey 6° 8II- rey ESTEE L°I0ol GEO Osey= as BL L£°8S EVL9 O86l yquoy yquoy qeax &q aatqetnumg 6°0/7Z Cees €°€/Lt 8°28 1°86 IEA 9° 9%5 LG WAG G°Ts oF 9 990 La/s8 [LES L°8/%7 9° COL 9°O0I fA) L «Gis Che OL GaES 7°99 AON Hee] LC €°68- 6°L/%77 @° SOT 8° LOL 9° ey- 6° 6€- ie EL OREE 6°19 S°69 290 6°€7/7Z GAS 9°L/SZ Z°601 8° TOL Gacy= 6° 6€- €°tl O°TL 6°19 7° OL dag Gc/8e 3G CL- © OL/ Ge Cll POOL 1 rkG= 3G Ly—=" = OL T°9 7°6S 869° 89 3ny 0°S/E 1°99- G°07/62 9°68 LE GOL Sas "byl € 4 fe KS é°SS O79 Tue L°O1/Ot 8° EL- 7° S1/8 T° cot i col G0S= Wp Sue 8°S 8°S £°9S Ste) unt 6 TL/Et, ~“92GL= Z°02/1 CCl GAOL “6:66 46 9€= O°9h -2£°€l 9°79 TH AeW 6° 1/91 7°0/ST 6°8L- 0° 61/62 L°16 9°00T Ess Uh Gi 6°L 672 7°8S 8°S9 ady 6°71L/9L 6°8IL- G°61/Z JES TEN 7° COL €27S- Ga0S= 6°0 6°0 ES T° 6S rey €°€/61 8253= 0°3/LI 6° LOL Ge LOL Le Gi = 6° 6€- Carl L°Oor i LS) 8°69 qed GEGL/7CG -8¢S9- €°6/S 4° OLL SeLOL. —~2ach= sh°Se=" Gr¢v— -Si@r 21269 TL 7Z uer O86L 40F ATYWUOW agnoyq/Aeq [a anoy/Aeq yo sw AT Tw ATW Tsu [qu aqu Myyw 8 9T9UFL 56 Tide Height (cm) 120 A 4 EH A A A 0 4 Oo Oe ou un Oun) On ae o 8 4 9 (oO MR 90 4 4 0 0 A ; On man mec: Migiaee Ree F 0 MHHW 60 0 0 ON rRe 0 0 MHW 0 0 0 -Meon 4 - Extreme 30 = E °o : MSL nO . tS ° eS -30 MLW MLLW -60 o A & A 4 A A EH - Extreme High -90 MR - Mean Range A MHHW - Mean Higher High Water MHW - Mean High Water MSL - Mean Sea Level MLW - Mean Low Water MLLW - Mean Lower Low Water EL - Extreme Low E -120 L Jan Feb Mar Apr May Jun — Jul Aug Sep Oct Nov Dec Annual Month (1980) Figure 19. Monthly tidal means and extremes for the seaward end of the FRF pier, 1980 150 190 Datum NGVD 50 -100 0 1 5 10 20 30 40 50 60 70 80 90 99.9 Percent Greater Than Indicated Figure 20. Hourly tide height distribution, 1980 Dif Highest High-Water Level (cm) NS. i fo) @ Os noe es C110. |S 30>. 014,050 om 0.3 0:5)" 0!8I 2 BCs) ey A0@) 20 30 50 70 90 Percent Greater Than Indicated a. Daily highest high-water levels | | | Oo ips) pb oO oO lo) i fe) Oo Lowest Low-Water Level (cm) 0.1 O35), 7,0'50 10'8S! 2 Sat Sua HO 20 30 50 70 90 Percent Lower Than Indicated b. Daily lowest low-water levels Figure 21. Distribution of 1980 daily highest and lowest tide levels, referenced to NGVD of the daily highest tides, the level exceeded 111 cm (NGVD) (i.e., 102 cm above the 1980 msl); likewise, for 1 percent of the time the daily lowest tides were less than 98 cm below NGVD or 107 cm below msl. 119. The following tabulation identifies times during the winter storm season months of 1980 when spring tides caused by perigee-syzygy alignment of the planets could be expected to produce extreme tidal heights: Date (Mean Epoch) Type of Tide 18 January, 2200 hours EST Pseudo-perigean spring 16 February, 1600 hours EST Perigean spring 16 March, 1500 hours EST Perigean spring 23 October, 1230 hours EST Proxigean spring 21 November, 1100 hours EST Perigean spring 58 120. Wood (1978) discusses perigee-syzygy and the occurrence of coastal flooding (when coincident with strong, persistent onshore winds) associated with the reduced lunar distances during perigean spring tides. Wood attrib- utes this to the reinforcing effect of the alignment of the sun and moon's gravitational forces on the earth and gives many examples of the effects this may have on the coast. This perigee-syzygy alignment, Wood states, may cause tidal flooding within a period of 1 to 3 days following (or in some few cases, a day or so preceding) the mean phase or epoch of the perigee-syzygy align- ment. Tide heights in excess of 100 cm were in fact observed on 16-19 January, 17 February, 24 October, and 22-24 November. 121. The highest tidal heights, though, were not coincident with the perigean alignment but more nearly correlated to strong nonastronomical forces such as persistent onshore winds and high waves. The highest and second high- est water levels observed were 118 cm on 2 March and 116 cm on 5 January, respectively. 122. The lowest water level observed was -119 cm on 16 March, a time when tides were expected to be higher than normal. A high-pressure system and sustained offshore winds dominated the water level producing forces and resulted in the annual extreme lowest tide height. Water characteristics 123. Temperature. Daily sea surface water temperatures at the seaward end of the FRF pier are presented as a function of time in Figure 22, and the distribution of temperatures is shown in Figure 23. The difference in daily temperatures was greatest during July when a 9° C change was observed over a 24-hour period, see Figure 22. This difference is attributed to frequent off-~- shore winds which blow the warm surface water offshore allowing upward and landward circulation of the much colder bottom water. Onshore winds, on the other hand, reverse the circulation pattern, piling up surface water along the shoreline and creating a seaward return flow along the bottom. 124. As can be seen in Figure 23, for less than 20 percent of the time during 1980 the water temperature exceeded 20° C, while for less than 10 per- cent of the time the temperatures were lower than 4° C. Seasonal distribution of the temperature indicates the coldest temperatures occurred from January- March, while the warmest were from July-September as might be expected. 125. The monthly mean sea surface temperatures measured at the seaward end of the FRF pier (see tabulation below) varied in phase with the air oy) TEMPERATURE (°C) 20 TEMPERATURE (DEG C) 1s 10 5.0 10.0 15.0 20.0 28.0 30.0 35.0 0.0 WEEKS Figure 22. Sea surface temperatures, 1980, for the seaward end of the FRF pier 10° 10° 10° PERCENT GREATER THAN INDICATED JAN-MAR 80 APR-JUN 80 JUL-SEP 80 OCT-DEC 80 ANNUAL 80 Figure 23. Annual and seasonal distributions of sea surface temperatures, 1980, at the FRF 60 temperatures presented previously, but the temperature ranges varied inversely from those of air temperature. July was a time of maximum range in water tem- perature and minimum range in air temperature, while February's ranges were at a minimum for water and a maximum for air. Sea Surface Visibility Month 1980 Temperature, °C m Jan 6.8 3 Feb BAS 1.4 Mar Bya5) 1.0 Apr v4 259 May 16.2 De Jun T8ic5 sia) Jul 20eo 4.6 Aug *“ 3.4 Sep 22% 1) 29 Oct 19.0 1.4 Nov 13.2 1.0 Dec 8.9 0-9 * No measurement. 126. Figure 24 shows the daily difference between the surface water temperature and the air temperatures measured behind the dune 1.5 m above ground. This temperature difference can be important to coastal engineers when assessing storm surge and wave growth values because of the modification of wind stress and, consequently, the transfer of momentum from the wind to the sea surface. When the air is cooler than the water, increased turbulence causes increased momentum transfer for a given wind speed; conversely, when the air is warmer, a stable condition results and less momentum for a given wind speed is transferred. The largest difference was 16° C which occurred during August. During October through February, the water was warmer than the air occasionally by more than 10° C. March and September are periods of transition, with warming and cooling of the coastal waters occurring respectively. 127. Visibility. Visibility in coastal nearshore waters depends on the amount of salts, soluble organic material, detritus, living organisms, and in- organic particles in the water. These dissolved and suspended materials 61 Jatd qYyJ ay. Jo pua psemeas ay} oz ‘086 ‘saouazazzIp einjzeraduay r3aqeM/aty Wz: WOWS O31vWiis3 dW31 U31UM ————* paysnipo Gaaiinii’ "9% 9ansty 06 $8 08 SZ 01 $909 5605 Sh Ob pe szoz sions | sz oz si0i ¢ on onono er) ) auasayyig (Jo dwa) adojing das /aiy PESZO2 S101 ST sea, us Ae ee Aeq nvr mow JaWIOM 310m ae JOWIOM ay 62 change the adsorption and attenuation characteristics of the water which vary daily and throughout the year. Daily water visibility measurements made at the seaward end of the pier are shown as a function of time in Figure 25. 128. The daily visibility is highly variable. Fifty percent of the time the surface visibility at the seaward end of the pier is less than 2 m (Figure 26). Visibility in excess of 6 m occurred about 10 percent of the time (or 30 days) during 1980, predominantly in July, August, and September. The greatest range of visibility occurred in August when greater than 5 m changes over 24 hours were not uncommon. Visibility varies much the same as surface water temperature (see tabulation, paragraph 125); onshore winds tend to bring clearer surface waters to the coast, and offshore winds produce up- welling of more turbid bottom water. Current Data 129. Currents measured at the seaward end of the FRF pier and 500 m up- drift of the pier on the beach are discussed in this section. Monthly and annual summaries as well as time histories of the daily values (Figures 27 and 28) are presented. The monthly average surface current speeds (see tabulation on page 67) were strongest toward the south at the pier end during the winter months. These currents were caused by predominantly northerly winds and per- sistently high wave conditions. From April through September, the winds blew predominantly from southerly directions and more frequently produced north- wardly moving currents as was especially evident in the wave-induced beach currents. 130. Current speeds were generally higher and the seasonality of the current direction was more evident on the beach than at the seaward end of the pier. 131. Peak current speeds were generally higher and more frequent for southward flow than for northward-moving water except for the persistent northerly currents on the beach during the summer months (Figure 28). Survey results 132. Weekly pier surveys from both sides of the pier and time histories of bottom elevations at selected locations along the pier are presented in Appendix C. 133. Bathymetry. Figure 29 is a contour diagram of the 1980 beach and nearshore bathymetry; the offshore data are not included due to the question- able accuracy of the depth information. 63 VISIBILITY (MH) 4 (M) VISIBILITY WEEKS Figure 25. Water visibility, 1980, for the seaward end of the FRF pier JAN-MAR 80 APR-JUN 80 JUL-SEP 80 OCT-DEC 80 ANNUAL 80 l 10 PERCENT GREATER THAN INDICATED Figure 26. Distribution of visibility measurements, 1980, at the FRF 10° 64 22g AON ayi 3e 420 das zatd qyq ay. Fo pua premeas ‘0861 ‘peeds querino a0esans (0861) bay ine une Aow aBesane AjylUO,) Ge "LZ eansty vor Oll 00! 00! (S/wd) psomyynos (S/w2) Psomyys0ON 65 gatd qyq eyq Fo 3FTApdn w QOS YyOeeq ayq worz poinseow ‘Qg6l ‘UoTIDeATp pue paeds quazand aoezing “gz aan3Ty abeiane AjyJuOW) = =r (0861) Bny ine une uop Ol 00! ae HT TT Paina 00! (S/w) psoOmMyyNOS (S/wd) PsomuLJON \ 66 Mean Surface Currents, cm/sec* Pier End Monthly Monthly 1980 1979 1978 Average Beach 1980 Jan 26 15 15) 19 6 Feb Syl 22 37 30 19 Mar 8 20 37 22 4 Apr 4 10 15 10 6 May 15 13 10 13 3 Jun 2 21 -1 7 -19 Jul -1 6 4 3 -22 Aug 8 7 4 6 -10 Sep 4 14 12 10 -14 Oct 4 8 10 7 27 Nov 19 9 14 27 Dec 13 7 9 10 14 Annual Mean ala 12 11 ial 3 * + = southward; - = northward. Distance (m) -100 © 100 200 300 400 500 600 700 800 900 1000 1100 : ee ee ee Depth (m) Distance Seaward (m) Figure 29. FRF bathymetry for October 1980 134. Near the pier, contours deeper than 3 m were significantly modi- fied. The 7-m contour diverged some 250 m towards shore, but the 3-m contour was relatively unchanged showing only a 20-m change. This bending of the con- tours near the pier is persistent throughout the year, although the absolute depth of the trough under the pier changes as a function of changing wave and current conditions. 67 135. Pier profiles. Between April and September, the profiles under the pier had a consistent shape and only about a 1-m variation seaward of the local msl beach intercept (Figure 30). During the winter months January through March and October through December, the profiles exhibit a much more . varied shape and large changes all along the profile (Figure 31). 136. Figure 32 shows the magnitude of the change in elevation as a function of the distance along the pier. The development and movement of bars account for the largest of the changes. 137. The weekly profiles from both sides of the FRF pier presented in Appendix C show when the bar system developed, how it moved, and when it was no longer present. As the bathymetry shows, the pier's influence causes these profiles to be considerably different from those farther than 150 m north or south of the pier. 138. The variations of bottom elevations as a function of time through- out the year at a select number of stations are also presented in Appendix C. Large changes over a short time are generally attributable to storms which cause rapid bar movement and large changes in bathymetry. Gradual changes over a season are associated with pericds of varying wave conditions and re- flect accretional or erosional pericds. The largest changes occur nearshore where bar movement is the greatest. Photographic data 139. In this section, photographic data used to document the beach condition in the vicinity of the FRF are described. Figure 33 shows samples of daily photographs of the beach taken from the pier looking both north and south. The cut seen in the 20 August photograph is a summer feature and occurs after periods of persistent southerly winds. During 1980, the cut was less dramatic than in prior years and was evident for only a short time in late August. 140. In addition to the daily beach photographs taken, quarterly aerial photographic missions were flown. Table 9 is an inventory of the photography obtained during 1980, and Figure 34 is a sample photographic negative showing the FRF pier on the 16th of July. Sediment Data 141. In this section, results of sediment analyses of sand samples taken from the foreshore throughout the year are presented. In addition, re- sults are presented from one survey in October along a 30-km-long transect 68 ELEVATION ABOVE MSL (FP) ELEVATION ABOVE MSL (Mm) 100 200 300 400 YT) DISTANCE (AM) a. North side 100 200 300 400 500 DISTANCE (MAM) b. South side Figure 30. Pier profile envelopes, April-September 1980 69 600 ELEVATION ABOVE MSL (FM) e 100 200 300 400 500 600 DISTANCE (AM) a. North side ELEVATION ABOVE MSL (Mm) 8 100 200 300 400 500 600 DISTANCE (FI) b. South side Figure 31. Pier profile envelopes, January-March and October-December 1980 70 Change in Elevation (m) 5.0 — North Side ---- South Side 100 200 300 400 500 Distance Along Pier (m) Figure 32. Bottom elevation changes along the FRF pier, 1980 71 500 zatd gyq ay. worz yAIoU BuTYyooT sydea8oq0yd yoeag “EE aan3Ty O861 3ny OZ ‘AeTA YIION 0861 AeW OL ‘Meta YINog 0861 dad 4 ‘MaTA Y INOS O86 teWN SI ‘Mata YqION M2 Table 9 1980 Aerial Photography Inventory (Negatives) Date_ Flight Line No. 1 Flight Line No. 2 Flight Line No. 3 Film Format 16 Jan 2 miles north to 2 miles Color south (1:6,000) 2 miles north to 2 miles Color south (1:2,400) 16 Jan Cape Henry to Cape +2 miles north to the Currituck Sound to B/W Hatteras (1:12,000) pier (1:6,000) Atlantic Ocean (1:12,000) 15 Apr 2 miles north to 2 miles Color south (1:6,000) 2 miles north to 2 miles Color south (1:2,400) 15 Jul Corolla to Oregon 2 miles north to 2 miles Currituck Sound to B/W Inlet (1:12,000) south (1:6,000) Atlantic Ocean (1:12,000) 15 Oct Corolla to Kitty B/W Hawk (1:6,000) from the seaward end of the pier to the 33-m water depth. 142. Between 4 January and 30 December, 130 surface sand samples were taken from the upper swash zone of the foreshore, 500 m updrift from the pier. Weekly samples were taken from January through June and during December, while daily samples were taken from July through November. Table 10 presents sta- tistical parameters of the sediment distribution for each sample, and Fig- ure 35 shows the mean grain size as determined from CERC's Rapid Sediment Analyzer (RSA) analysis. Considerable scatter is evident, but a trend for smaller sizes during the relatively low wave conditions during July and larger sizes in December and January (times of high wave conditions) can be seen. Caution should be exercised when using the mean of a sample to infer typical grain sizes found on the beach. Frequently, the mean may not be a true indi- cator of a predominant size found in the sample, but simply an average based on the distribution of sizes. This is particularly true as the sizes become more coarse, since the analysis reports frequencies at 1/2-phi intervals and increasingly larger intervals of sizes occur between classification limits as shown in the tabulation on page 77. 143. As an example, a sample taken on 20 November 1980 is described on page 78. The frequency distribution, given in the tabulation, shows a 73 Og6L ATur 91 uexed AMA FO ydearzojoyd [etsae atdues "ye aansTy 74 Table 10 Statistical Parameters of the 1980 Foreshore Sediment Samples Standard Median Mean Deviation Skewness Kurtosis Date Phi mm Phi mm phi phi phi 0104 0.84 0.560 led 0.431 0.91 1.23 321 0109 1.71 0.306 1.79 0.289 0.54 0.74 2.87 0119 0.76 0.589 1.10 0.467 0.81 1.34 3.53 0123 0.98 0.508 1.06 0.480 0.80 0.41 2.99 0201 1.42 0.373 1.40 0.380 0.86 =0.17 2.49 0402 0.90 0.537 1.01 0.498 0.72 0.31 3.51 0413 1.33 0.399 131 0.405 0.76 -0.03 2.34 0503 1.12 0.462 1.24 0.423 0.63 0.37 3.49 0606 1.83 0.282 1.81 0.284 0.64 -0.90 4.58 0613 1.40 0.380 1632 0.400 0.80 -0.69 3.29 0701 1.46 0.364 1.58 0.333 0.53 0.45 2.59 0702 1.69 0.311 1.75 0.297 0.65 -0.54 4.97 0703 1.68 0.312 1.65 0.319 0.95 -0.44 3.05 0704 1.68 0.311 1.74 0.300 0.65 -0.21 3.46 0705 1.89 0.270 2.04 0.243 0.82 0.53 3.34 0706 1.45 0.366 155 0.342 0.67 0.41 2.66 0707 1.80 0.288 1.88 0.272 0.49 0.58 2.64 0708 0.41 0.752 0.62 0.649 0.87 0.57 2.13 0709 2.10 0.233 2.18 0.220 0.57 0.66 2.84 0710 2.20 0.218 223 0.213 0.41 0.06 2.95 0711 1.97 0.256 1.95 0.258 0.52 -0.72 4.49 0712 1.93 0.263 1.93 0.263 0.49 -0.11 2.91 0713 0.98 0.505 1.21 0.431 0.66 15727) 4.06 0714 1.37 0.386 1.48 0.359 0.49 0.53 2.70 0715 1.86 0.275 1593 0.263 0.47 0.67 2.86 0716 1.96 0.258 2.02 0.247 0.59 0.06 Sieih2) 0718 2.06 0.240 2.03 0.245 0.73 -1.26 6.51 0719 1.74 0.299 1.88 0.271 0.58 0.53 3.67 0720 1.87 0.274 1.96 0.257 0.47 0:57 2.96 0721 Pxeilal 0.232 217 0.222 0.49 0.54 2.89 0722 1.99 0.52 2.00 0.251 0.42 0.24 P3417) 0723 2.01 0.248 1.99 0.252 0.54 =1.92 10.20 0724 1.80 0.287 1.87 O7273: 0.46 0.19 3). 2i1. 0726 1.79 0.289 1.90 0.268 0.52 0.78 2.87 0727 0.78 0.584 0.98 0.506 0.54 ee) 3.41 0729 1.41 0.375 1.54 0.343 0.46 0.83 2.83 0730 1.25 0.420 1.41 0.376 0.74 0.39 Sil 0731 1.32 0.400 1345 0.366 0.63 0.40 2.83 0801 1.82 0.283 1.91 0.266 0.54 0.25 4.08 0802 Vid 0.293 1.88 0.272 0.61 0.05 3.32 0803 1.69 0.310 1.76 0.295 0.51 0.37 22, 0804 1.53) 0.347 352 0.348 0.74 =0)51 Syoaly/ 0805 1.97 0.256 1.99 0.252 0.49 0.04 34.23 0806 1.81 0.286 1.82 0.283 0.58 0.18 255 0807 1.39 0.381 1.55 0.341 0.74 0.77 3.04 0808 1.44 0.368 1.56 0.339 0.64 0.50 393) 0809 LO57, 0.337 1.65 0.318 0.69 (sala 3.29 0810 1.12 0.459 1.18 0.443 0.68 0.15 2.90 0813 1.58 0.334 1.68 0.313 0.51 0.57 2507 0814 2.10 0.233 2.08 0.236 0.47 0.07 235 0815 1.67 0.314 1.66 0.315 0.62 -0.45 3.92 0817 1,31 0.403 1.38 0.384 0.55 0.08 4.14 0818 Lye: 0.459 1.30 0.406 0.62 0.91 3.16 0819 1.10 0.465 Dalz 0.460 0.75 0.05 2.48 0822 1.05 0.483 i413 0.458 0.53 O33 3.34 0823 0.81 OFS 0.99 0.504 On73 0.61 2.66 0824 0.83 0.562 0.99 0.505 0.73 0.62 2.50 0825 0.83 0.563 1.01 0.495 0.67 0.75 3.56 0826 0.14 0.908 0.47 0.720 0.95 1.07 2.90 0828 0.39 0.762 0.49 0.714 0.43 1.49 5.47 0829 123 0.428 1.34 0.396 0.75 0.26 2.41 0830 178 0.292 1.78 0.292 0.62 -0.88 S25) 0831 1.29 0.409 1.33 0.399 0.69 0.15 1.96 (Continued) 75 Table 10 (Concluded) Standard Median Mean Deviation Skewness Kurtosis Date Phi mm Phi mm phi phi phi 0902 1.87 0.274 1.91 0.267 0.62 -0.68 5.73 0903 1.69 0.310 1.79 0.289 0.56 0.57 2.37 0904 1.69 0.310 1.79 0.290 0.60 0.49 2.76 0905 0.77 0.588 0.92 0.530 0.79 0.47 2.69 » 0908 0.15 0.899 0.46 0.728 0.85 1.86 5.10 0910 1.41 ONS Ti7 1.46 0.364 0.67 0.24 2.51 0911 1.26 0.416 1.34 0.394 0.56 0.47 2.94 0912 1.47 0.360 150 0.354 0.68 -0.46 3.87 0915 1.49 0.356 1.58 0.334 0.52 0.10 2.49 0916 1.43 0.372 1.56 0.339 0.64 0.59 2.99 0917 151 0.352 1.59 0.333 0.56 0.36 3.00 0918 1.43 0.371 eo 0.337 0.54 0.79 2.85 0919 1.01 0.497 15 0.451 0.78 0.38 2.88 0922 1.04 0.486 iat 0.464 0.93 0.17 2.51 0923 37 0.387 ESA: 0.351 0.67 0.49 3.24 0924 1.04 0.486 1.07 0.477 0.79 0.20 2.28 0925 1.38 0.383 1.49 0.355 0.60 0.55 2.62 0926 1.43 0.370 157 0.337 0.52 0.91 3.11 0929 1.76 0.296 bearer) 0.292 0.43 0.12 2.30 0930 525 0.420 1.32 0.400 0.58 0.43 2.58 1001 1.39 0.380 1.45 0.366 0.71 -0.06 3.01 1002 1.16 0.448 1.19 0.437 0.90 -0.04 2.16 1003 0.67 0.627 0.90 0.535 0.82 0.54 2225 1006 0.99 0.505 1.06 0.478 0.49 0.37 2.94 1008 0.43 0.741 053 0.691 0.43 0.63 3.86 1009 0.96 0.515 1.08 0.473 0.68 0.43 2.93 1010 0.97 0.510 Vers 0.456 0.76 0.18 2531 1011 2.41 0.189 2.45 0.182 0.29 0.68 2.61 1014 1.19 0.437 M27; 0.414 0.70 0.23 2.29 1015 159) 0.333 1.62 0.324 0.55 -0.27 332i, 1016 1.69 0.309 ea 0.302 0.48 -0.29 3.59 1017 Msi62 0.324 1.68 ONSTT 0.5) -0.09 3.06 1020 1.56 0.340 1.62 0.324 0.59 0.10 2.92 1023 2.38 0.192 2.39 0.191 0.06 Sarat 14.76 1024 1.49 0.357 15.6 0.340 0.37 0.48 2.34 1027 0.93 0525 0.92 0.528 0.79 -0.01 2323 1028 1.14 0.453 125 0.421 0.65 0.41 Zao 1030 1.08 0.473 122 0.428 0.72 0.49 2.90 1031 1.10 0.466 1.18 0.440 0.68 0.09 3.24 1101 1.45 0.366 1.58 0.333 0.53 0.74 2.90 1103 1.05 0.486 1.13) 0.457 0.50 0.63 3.04 1104 0.81 0.568 0.95 0.518 0.54 0.86 4.03 1105 0.93 0.526 0.98 0.507 0.62 -0.09 3.65 1106 23 0.427 37 0.387 0.58 0.53 2.73 1107 -0.04 1.030 =0)01 1.005 0.23 0.74 4.66 1110 1.53 0.347 1.59 0.333 0.57 =-0.38 3.94 1112 1.45 0.366 nAns yy 0.336 0.58 0.54 3.00 1173 1.44 0.368 1.50 0.354 0.52 0.26 2.96 1114 1533 0.397 1.41 0.376 0.56 0.29 3.18 1117 21 0.433 1.33 0.399 0.64 0:23 3.02 1118 0.96 0.513 ala 0.464 (eZA7/ 0.35 3.29 1119 0.94 02522 1.19 0.439 0.71 Le5 3221 1120 0.18 0.883 0.28 0.821 0.47 1.86 6.74 1121 0.40 0.760 0.61 0.655 On75 0.88 2.88 1124 0.58 0.670 0.63 0.561 0.73 101 3.40 1125 0.84 0.560 0.98 0.507 0.70 0.69 2.95 1126 0.48 0.717 0:71 0.611 0.59 1.31 4.10 1128 1.16 0.446 125 0.419 0.78 0.40 2S: 1201 1.44 0.368 1.5 0.350 0.65 =0',.12 3.90 1208 0.57 0.674 0.82 0.565 0.80 0.76 2590) 1215 1.34 0.395 1.48 0.359 0.65 0.42 2.60 1224 1.07 0.475 1.21 0.433 0.58 0.63 3.25 1230 0.98 0.509 1.14 0.452 0.60 0.97 Sie a 76 MEAN SIZE (MM) : 0.4 05 06 07 0.6 09 0.t ree Fea FAR FPR RAY JUN JUL FUuS sep oct NOV OEC MONTH Figure 35. RSA-determined mean grain size of the foreshore samples taken in 1980, 500 m north of the FRF pier Phi Size mm Size mm Interval -1.00 2.000 -0.50 i egie a 0.00 1.000 0.293 0.50 0.707 0.207 1.00 0.500 0 1G6 1.50 0.354 0.104 2.00 0.250 0.073 ZisoO OL177 0.052 3.00 0.125 0.037 3.50 0.088 0.025 4.00 0.063 ; dominance of the 0.707-mm size (0.59) with some 1.000-mm (0.09) sizes present. The mean, reported at 0.821, is not similar to either size present. The mean is useful for generally classifying the material sizes on the beach; i.e., for distinguishing between coarse, medium, fine, or very fine sand sizes in a sample. The standard deviation is useful for determining the sorting char- acteristics of the sample; i.e., the similarity of the sand sizes. 77 120 1}e20"80 STATISTICAL PARAMETERS PHI M PHI MM,» FREQUENCY CUMULATIVE MEDIAN AA tees SIZE SIZE PERCENT PERCENT MEAN Kaan) seell 21.00 26000 0.00 O.O0STANDARD DEVIATIUN oa? 2.50 141d 063 063 SKEWNESS 1,86 0200 1.000 16.01 16564 KURTUSIS 6, 74 050 oT? 68,70 85034 1.00 500 6,25 91.59 1090 0394 2,77 94,37 2000 250 5463 100.00 2050 0177 0,00 100400 AUG PG 4,00 00603 0,00 100,00 144. In addition to the analysis of foreshore samples collected at regular time intervals, sediment characteristics were measured on one occasion as a function of water depth and distance offshore (Williams 1982). From 27 through 31 October 1980, grab-type sediment samples were obtained at 24 sites in a line parallel to the pier from -6.3 m water depths off the pier's end to -32.9 m water depths at the end of the transect some 37 km from shore (Figure 36). 145. The 24 sediment samples were visually and microscopically examined, and the primary grain size parameters were derived by analysis using the CERC RSA. The sediments were all fairly similar in color and composition and ranged from very fine to very coarse gray sand. In general, the samples from the -6.3 m contour seaward to about the -17 m contour (Figure 37) were gray, mod- erately well sorted, very fine to fine quartz sand, findings which are in agreement with the 1979 survey (Miller, 1982) of 13 short core samples taken from the shore seaward to a depth of -15.8 m. Sediments at sample site num- ber 14, taken near the crest of the second shoal, contrast the most with the other samples in the transect. The sediment in this sample was medium to very coarse quartz sand with rock fragments and broken shell fragments very similar to typical samples from the beach at the FRF. 78 for nt sample locations Figure 36. Sedime ey October 1980 surv Grain Size (phi units) Groin Size Std. Dev. (phi units) Depth (m) Coorse Sond \ 0.5 Medium Sond 2 0.25 = aah Fine Sond 3 0.125 3.5 Very Fine Sond 0.0625 0 0 Very Well Sorted 0.35 0.35 Well Sorted 0.50 0.50 Moderately Sorted 0.80 0.80 Moderately Sorted 1.40 1.40 0 5 PIER END I 0 Dp 6 7 15 t ore Ore 070 Ore 040 0SY 0SZ Ore 0zE a4 09€ ore Ore 0S0 0S0 0zE OcE 0S0 0S0 0zE 061 0S0 Oce 0€7 0zE OzE 0S0 0zE 0zE (N enz) uotq -2211¢ put puey 68 8's V/ € 6 Z° 6101 c'9 T= OFt= 0°T- Se 4 97S T9101 S LL v= 0°C- OF T= ca 9 4 c°9c0L 0 c'8 6 ey) 0°9 € l €OL 9° 0ZOT 0 oy) Sal Sé Sls, c 9 LTE c’6lol 5 c°8 v/ 0°” 0°97 9 L €0€ é Stor I c'8 iS os $9 9 cl 7€7 8° 910L 0 LSS q o's 0°9 c- ey) vAes €°9001 0 ol We 0°¢- Oats Gs 8 Lez L°Ttol € Ea9 8 0°83 o'e 8 vat 00S 6° 166 6 eS 7, 0°9 0°83 € 8 £09 S°LIOl 0 LEG € 0°” Sie 9 6 LOZ S°0z0I 0 9°E € o's One I 6 LTE 0°9¢0T 0 a9 9 0's c°S S Il 9°Icol 9 ove 8 0°8 0°83 L Or €OL c°€Z0l 0 I's s°9 s°9 One Wt) 6 00% 6°720L 0 U's € 0°47 0°S0 Uf val LIZ 9°420I 0 78 S°8 S°8 ¢°80 8 val viral 8° LIOL vat Ove Lil OT O'IT 9 IT Les 8°clol 9 78 9 o's 0°90 S Il 00 ETEOL 0 9 l 0°8 0°6 8 02 0€7 f° 6101 €1 Ess c°8 S°8 0°6 " IT O18 L° L201 0 c'8 A OnE 0°6 9 L 977 T° 9€01 0 l orl ol 9 8 £09 9°9c0I W 9°¢ 9 0°9 0°9 € Il 02c 9°ccol S Ea I 0°? 0°€0 c- uy) LOL 6° €Z01 0 bee) Seca Sac 0°é= c- S LEZ S°0zOoT y GL S o's o°s £ 7 £0€ 6° €00I 6 ESO 9 OL 0°8 if 8 00S 9°?cor 0 I OT OT I 8 Lec 9°ICOL 0 o'r I 0°? Ove 4 IT 0€z L°Olor 6 000 L°Oror 0 9es/W Do Jo Jo Jo Jo Spusisy qui ung “uot? peedg yutog aanqe ainze ainqe ainje aanssaig ainssaig -eqtdtoa1g putq Maq -dtadway -szadway -sadway -sadway dtaayd jo unouy puey qing qing MOT u3TH ~Souny 129m Aig suotzeArasqg TedTs0ToOIOaqaW ATTeq Og6l Azenuer ev 2T4deL LT (4 9 "7 "7 91 oT 97 9 8 97 9 "7 ot € 61 97 S I 97 "7 8 "7 S "7 "7 oI 91 oT 8 wy AATT{ Iq -TSTA Oot oor oot Oot oot Oot Oot Oot 00 06 0 Gz 001 % 19Aa09) pno[) %00T-0 AyTsuequy :[e303 ATYyQuoy taseraae ATYyQuoy s a SUOTJIpUO) z3ayqeamM 8ut[teaeig 0€Z0 0€20 0€Lo 0€L0 0€Lo 0€LO 0€L0 0€LO 0€Lo 0€L0 0€L0 0€60 0€Lo 0€Z0 0€Lo 0€Lo 0€L0 0€LO 0€L0 0€L0 0€LO 0€Z0 0€LO 0€20 0€LO 0€lo 0€LO 0€lo 0€L0 0€LO 0€LO aut, T€ oe 62 82 LZ 97 mN OT WH NANNNN | ANMNTN OM DNO ANM~TN OR ANDO =) An re ee ee ee A3 99 >T2303 ATYQUOW 0°9 c- c- € 7° 610L 61 64 :e8eraae ATYAUOW O€e 8°OL (Ge 0°I- 0°0 Ue S 192 z° 6101 0 "7 os O€LO 62 os eS I- O°? 0°” I 6 700 8° 7101 0 9% Oot O€L0 882 Oz £9 S- O°T- o'r c= 9 0cL z*T2oL 0 97 0 0€L0 =e Ore (an:) c- 0°0 ha & 0 L L497 £° LOOT 9 91 oot = ss 0€40 92 07 £°6 S 0°9 OL € 6 LOS T° 2tot 0 91 oot 0€L0 8 SZ Oze I's L OL O°L L or Lee 8°9TOL 8 I oot + i O€L0 842 0¢2 9°€ ol O°rT 0°?L 6 61 Ole T° 2L0t 0 "7 0 0€L0 8=E@ 0¢2 9°E ol 0°OL 0°OL 9 SI LOL 8°STOL I I oot i O€L0 2 0€z Sy, S 0°9 OL M7, a LIE T° 710t 0 91 0 O€L0 =z 0v Duy € 0°49 0°s (ES 8 00” 7° LOL 0 I os + i O€L0 802 04 ly I 0°? Oe 8- 9 019 €°SZOt 0 97 06 o€40 «6 Ole 9°? cI- 0°6- 0°8- T= I LZ €°9Z0L 0 "7 0 oc€LoO 81 as £°6 o= S°t- 0°9- €= Il Lez 7° €LOL 77 9¢ 06 o€40 =OLT OLT co q 0°9 Gicd z or oel 9°€00I 0 Wi4 oot a 1 o€40 «91 of Sy) I 0°? Ove c- 6 004 9°?@zoL 0 91 SL 0€40 = =ST OLT T°¢€ Se 0°€- 0°?- Op € €° 6201 0 "7 0 o€l0 = WT 0c c°9 95 0°?- 0°0 VD 9 022 €°620L 0 Le 0 o€L0 «ET 0zE lees €- O'T- 0°0 Y= S Let zc Ltol 0 97 0v o€40. ZI Ore ey) 8- 0°S- OF7= S= A LTE f° OcOT 0 97 0 ocLo- OTT Ofe Sil 0 0°0 0°0 Le € 971 7° 600T 4 8 oor = ss 0€loO- OL O€ce Te BG O'I- 0°0 9= € 004 0°920L 0 8 oot O€40 6 OcE a9 Es Onis 0°€- YP S LIZ L° 6201 9 97 0 o€L0 «8 Vix 8°LIOL €l oczo LL 07 Te c- 0°0 O'l 9= 4 00S €°9Z0L 0 "7 oor o€L0 9 0ze a9 L= 0°S- O:7= C= 0 Ole 0°LZ01 0 "7 ol ocLo 86S ote c9 (6 05 9= 0275 Or- 0 004 6° €ZOL 0 97 09 o€L0 4 00€ a9 i= O°l- Osl= 8- iS VAS 0° 2201 0 97 OL ocelzo 6€ Ole (an: ) i= 0°8- O°l- 8- c- 0272 €°97Z0l 0 Vi4 0 o€lLo0 72 Ole £°6 L= ORe= OMe= l= c= LOL 8°LIOL 8 97 or oezo OL UY od (Nanay) das/m D, Jo Jo do Jo spuer] qu um “UOT? wy % Aqtsuequy suotztpuop auty Aeqg Voda uot? paadg yutog 9 aainjze ainqye ainye aainje aansseig oeinssaig -eqrdtsaig AQITIq 1aao0g9 zayqyeaK A A -991TG putm aAaq -iJedway -zedmay -1zadmay -iadway dtzayd jo qunowy -ISTA pnot9 But[teasig putm puey qing qrng MOT y3tH -soujy %00T-0 puey 32M Arq €V eT9deL SUOTJEATASGQ [eOTSOTOAOazaR ATTeq Og6lt Arenagayz A4 >otel 062 Ost OST 09 02 o£ 00€ 047 Oce 00€ 002 OST 0” 0%7 002 08st O€e 062 OL 0” 00€ OL 07 08T O8T 4 O8T 027 O€e 02 02 (N enz) uot -291TG pUutM puey fon) mn Ww woo DO AMOMr~OMT DANE NO ONnTMNN ADATOTN OMNNNN OFPMND S ” (al €1 0°! O°€L 6 val LOL or 0°Or S‘Oor 6 LT LOL or 0°Or 0°Or 8 él "19 9 OL 0°8 9 OL Ort € o's OL 9 8 Le (E 0's Ga9 9 LT VAG 8 0°Or ‘er 8 oT 1972 9 0°8 0°Or 6 6 LIE (4 ONE Oey) € at LtZ I o°s 0°83 9 (a6 01d IT O'rT O°IT Or 1e4 EL 6 0°OL O°IT 9 IT L08 € o's Ge € 91 VKG ST o°ST 0°ST ST 1¢ Ie OL O°€! S°91 8 LT L09 9 OvL 0°8 7) vA’ OLT 0 Ove 0°S 4 rai Lee € 0°47 o°s € 81 0€z 9 OL 0°8 c 8 0€L {62 a4 Wy) 4 IT 027 9 0°83 0°Or L €1 LEZ S 0°9 O°L 4 9T €or OL 0°OL 0°OL 6 ST LTE IT 0°?r 0°€I € 81 L09 4 Ove 0°" Or L 00% € 0°” 0°s € 6 L4Z 7] 05S 0°9 Te 8 LOT We 0°C- 0°T- b= I £01 c- 0°0 OT eas I LOL (Be Ors 0°0 7 y= I £00 ES Ony= ORES T= c £0€ Jo Jo Jo Jo Jo spueiy UTO ainye ainqe ainye ainje ainssaig aeq 4 -Jedway -izadway -szedway -a1adway 4nd qIng MOT 43TH 394 Aaq 68 9° 8I0l 9° 7001 €1 8° CLOL 0 L°Tror €1 €°8zol 0 0°920T 0 6°0ZOL 0 0° L00T 6°0ZOL 9°1cOl €° SOOT 9° €00I €°SZOl L°O€OT T° TLol €°97OL L° €or €°8zol L°600T TOL cT2or €° LOOT 7° 710L 7° 600T 8° LTOT 9°970L 9°eZ0L 6°0ZOT 9° €Z0T ZOOL 8° ELL L°O€OL qu wu “UOT ainssaig -eq4tdtse1g dT1ayd jo JuUnouy -sowjy - ooonro NMOOr - - Ie ie CI) moowuo 7nOoOtmMo suoTzeArasqg [edTsoTo10a3aRj ATTeEG Obl YoIeW “Vv 9T9eL AIT -TSTA SZ Oor + oor = SZ OoL = oor 0v Oot 0or OoL my AQtsuaju] 1aao9 pnot9 %00T-0 :[e103 ATYy.UoP :aBeraae ATYyQuoy fy fy, SUOTITpUOD 13ay3e3q But[teasig 0€L0 0€L0 0€L0 0€L0 0€20 0€Z0 0€L0 0€L0 0€Z0 0€20 0€L0 0€Z0 0€L0 0€Z0 0€20 0€L0 0€20 0€L0 0€L0 0€LO 0€L0 0€LO 0€L0 0€L0 0€20 0€Lo 0€LO 0€L0 0€L0 0€Lo 0€Lo aut T€ 0€ 67 82 Lé 97 SZ 97 x4 (a4 1Z 02 61 8I LI 91 SI vas €1 8] Amann OmDAHO AN a ot te A5 a5 NNONM OCODOANR FBPOROMmM NANROSO O mAINWO WITT ODOO FFT NTD DETMN MO ooo oooo9o ocoo0od ooooo cooooo oomnon FAD HONOF NNAMNA DNAMNA NAF NMN NOWTNA Onn ane Ae ae Bt COO RA FARRAR ANA Ae “Oo - - 0°40 -22I1TG put pueyT putmM puey tod “aq ainye -Jaduay qing 29M It S*4t val 0°91 Il o°ST €l 0°62 Zl O°ST €L S°SI OL 0°91 €l 0°6L SL O°9L ot O°4vI 6 He! 6 Sey L ras 6 0°40 9 O'rT 6 O°€L rat O°4T IT 0°02 LI O° EC SL o€L0 92 oS + a OELOs 52 SC 09 0€L0 642 ot oclLO 8 €2@ 0 o€L0 2 0S 0€lo Iz 0” o€L0 02 0 ocLo- ot cL o€L0 8 OL ocLo =—LT 0 o€4o 809 ol oeLo 8 ST OoL - i o€lo 8 =4T oot ocLo ET 0” oc40 8a 0 o€Lo- =odTT SZ oelLo~ OL 06 ocL0 6 06 ocLo 8 SL oe4o 86k 0 oc4o0 9 0 OFZOrS Ss ool ocL0 = SL = i oc4o OE 0 = i oel0 82 Oot o€4o =O x: Aqtsuajuy ~4«suotztpuop owt Aeqg 1aa09 19y7e2q pnot9 But[teasdig %001-0 A6 > tal eho] 6€ :Te309 ATYQUOPW yee) ST ST 9¢ S*STOT 8S :a8ereae ATYIUOW 0€z [Eafe 02 G‘IZ 0°Sz 1e4 0€ LIL 9°€cOL 0 ST or ogso si TE O€T eG) 81 S‘6r 0°¢@ 02 62 IST c°ccor 0 SI 06 ST80 O€ 002 mL 81 S12 0°82 LT 82 vat 6° 6101 0 91 00 S70I 62 062 ay, ST 0°8t 0°€? SI x4 vaat 6° 6L0T 0 9¢ 00 O€L0 882 Ov 1°9 (al 0°ST S*6L IT 17 Via4 8° 9LOT 0 97 00 0€40 Lz 0v 1°38 oT OFEL S"6l LT VARs 7° OLOL 0 91 00 oocl = 92 m4 0°27 0°9¢ 6r E 9° COOL 0 IT . o€L0 8 Sz 21K G1é 0°¢? OL (a4 €Or 8° cLOL 0 91 0€L0 842 O8T LES 6T 0°61 0°02 81 97 €0€ 8°8L0L 0 91 Oot = i O€L0 8&7 0” c LT 0°8T S°02 a1 9c vr? c°0zOr 0 8 0v = i O€L0 2 61 0°02 i 4 61 82 0€7 L°Orot vK4 "7 06 O€L0 8172 0477 S21 Sale i 4 i KA 91 T€ £0€ 8° EOL 9 oT Oot 0€L0 02 097 6°€ 02 0°12 0°€? 0c VKG Ole S°LIOT 0 91 os o€40 «61 002 lots 81 0'6r 0°1z ST 1@ OTL 9°T2OL I 91 oot o€L0 81 09 LES €1 0°FT 0°9L €T 81 Ole €° 6201 0 viG Sz OfZ0R EL 09 [EAS IT 0°€T 0°9L cl 81 CC 0°970L 0 iA 00 o€lL0 «OL 0¢ o9 ral O°€L 0°ST vA! 82 Lee 8° 8I0L T Vi4 oot o€Z0 ST 097 WEY) 61 0°02 S°ce (a4 T€ LOE T° 2ror 0 91 oot o€L0 3841 047 Dey. Ié 0°€7 0°82 1e4 0€ 004 9° VOL 0 ViG os ooct €T 04¢ eS LT 0°61 0°c? 61 9¢ Ole c° Stor 0 "¢ SL 0€40 =I 002 Oa €1 0°9I S°02 cL 1e4 TLE S° 6101 0 97 SL o€Lo. =OdIT ral I 6 0°CL 0°9L 6 LI 907 c°O0cOL 0 97 Td o€40 OL 02 CL S 0°6 S*€l IT LI O€e 8° €10L I 9¢ SL 0cL0 6 02 I's €1 0°FI 0°9T 91 iG Ore €° LOOT 0 € OOL = x o€L0 «8 Seer S*9I a 4 61 8¢ Lee €° 8001 0 91 04 S x o€zo OL ST O°LT 0°12 81 67 004 0°900T 0 91 0v = x o€lo 9 ST O°LT a 4 val Via 007 7° OLOL 0 91 09 2 >I og€zo 6S rai O°ST 0°61 6 £2 £0€ T° TloL € 91 09 = rt ogl0 4 6 O°?r 729% 6 IZ 00% 9° Y10L 0 9¢ 09 ogc40 OE (ai CooL 0°ST a val VAM 8° cor é 91 os O€Z0n ¢ It 0°cr S°€L (ai 61 00% 9° SOOT I 91 Oot o€zo =O (N eNI[) Jas/m 9, a5 Jo a6 76 spusly qu wu “UOT wy % Aqtsuequy ~«suotzIpuon auty Aeg uot? peedg utog aainje ainze ainye ainjze asinsseaig einsseig -eqtdtdaig AAITIq daaog 1ayq.eaq -291TG Pulm Maq -iedmay -iadmay -1admay -1zadmay dT1ayd JO YUNoWy -ISTA pnot9 8uT[TeAeIg putM puey qing qing MOT 43TH =souny %00T-0 puey 324 Arq es se suoTJeAIasqg [edTsoToroajay ATTeEG Og6l AeH ov 2T9FL A7 a9 LT 8t L@ T° LTOL £7 0°92 S°SZ 61 9€ 0Sz 9 "C 0°Sz 0°Lz 97 €€ £09 7° €LOL 0sz GES "¢ 0°97 S°497 €Z LZ £0r T° STOT 062 T€ G°te S°tz G°€z 81 9¢ LIZ S°*STOL 060 Ey 6t 0°61 0°6r 81 97 00S 9° CLO OIL Te 6t 0°02 0°€2 uy, 82 00S S°6tort 002 ey 81 0°02 0°97 1Z 67 L0z 9°7@coL 0Sz T’€ Lt 0°6r 0°€2 €1 9% 717 6°7coL 020 ty val O°ota!l 0€ Cay, 1é 1 62 S‘81ol 9S 1? O°1? 0°¢¢ 1é £7 £09 8° EOL q 91 Oot 91 0°OL 00°C? al (a4 £08 c T2or 0 0¢ 06 Il val S°8I 81 67 LIZ 9°49C0L 0 "¢ Oor 062 OES (a4 0°€? 0°SZ (46 87 71Z T° ZTOL € 91 GL 0Sz IT’S Sac Sale Sauce (54 9C £0€ S°LIOL BG or Oot os L9 IZ Baa PKG (KG €€ 0cl T° ZTOL 0 91 Oot 0Sz 9) x4 0°9¢ 0°92 9¢ (fs Oot €°€ ol 0 91 GL 0Sz (eet) (a4 0°€2 SeSé 17 T€ 004 8° LTOT 0 00 0L eS (a6 0°Le 0°97 £7 6c LIT €°9720r 0 OL 0€7 Tee 97 0°12 0°0€ Sc €€ £08 S°LIOL 0 GZ 002 AS €7 0°97 0°9¢ SG 97 LOL 8°STOT 0 Ov OL [eey) 1é 0°¢? 0°4¢ (a4 67 LTE ST LLOL 0 os 0Sz qiy, (a6 0°€% 0°92 1é 0€ 00% £°600T 0 0v os Lecé 61 0°02 WAKE IT LZ OTE 6° 6L0L 0 00 os Eye 91 0°8I Gece IZ 0€ VLE S°LIOL 0 00 0Sz [EAS IZ 0°¢? S° 9% 0¢ 67 £0€ T° LTOL 0 SL 0S i? 91 0°61 0°92 (a6 8c vans ¢°1cor 0 00 09€ Eat 61 0°02 0°€? 61 0€ LOZ S°8toL 0 0v 06 lsat SZ 0°SZ G°SZ 6r 67 004 9°C7OL 0 Ov OL Ty 9¢ 0°92 OeSe, (44 67 val €°77or 0 Oo- 062 Ory) £7 0°97 0°9¢ SZ UAS OTE S*0201 0 OoL 0SZ 9 7¢ 0°SZ 0°82 €¢ cE OIT (am FA 0 SZ 3) (N enIZ) as/w 9, Io Ie an 6 spuels] qu wu “UOT wy Oh a uot} paadg yutog aanqe ainqe ainjze aanje ainsseig ainsseig -eqtdtsa1g AQITIq Jaaog A -99ITG putiM = Maq = -seduiay -1adway -sadway -xzadway dts9yd JO qunouy -ISTA pnot9 puTM puey qing qing MOT u3TH -Souny %00T-0 puey 23M Aaq suoTjeArasqg [edTs0ToOIOaaW ATTeG 0861 Aequiaqdas OIV 919eL AQtsuejuy :[Teq037 ATYQUoP ta8ezaae ALY QUoOW SuOT}Tpuo) zay.e94 Sut[Teaeig 0080 0060 0020 0€L0 0080 0€80 0€L0 STLO 0€60 EOL 00L0 0080 0020 0020 S790 S790 S790 0020 0020 SILO STLO 0€L0 aut] I€ 0€ 62 87 L@ 9% SZ iG £7 ce IZ 0c 61 81 LT 91 SI val €1 él EE Bs] Amati Oor~ ano a a] All >t al emo! 062 002 062 0s OLZ 0Sz (N eniy) uot? -d91TQ putm puey OT Ve das/u paads putm puey 02 81 €I IT 8 val 61 6r 0c Jo qutog aag 0°T? 0°8t 0°ST S*€L 0°Or 0°9T 0°6t 0°6L 0°02 Jo ainye -lJadway, qing 224 0°€? 0°6r SSAL o°ST ar | 0°6L 0°02 0°02 S02 Jo eine -Jadwey, qing Arq 81 61 1@ Jo sinye -Jadmay, AOT 17 €°0zOl él £08 9° 1ZOL 1 LOE €°SZoL 12 9€7 6° T20L 9L org c'LItOl 81 yA €°SZOl (G6 LTE 6° ZOOL LI €0L 0° Lz0T 61 07 L°37¢ol 14 €0€ 7° 6101 LI vaes 6° 6101 92 HET IT°Vt0l 6 004 €°7Z0L (x4 €0€ 0°920L LT LOE €°SZOL LZ LIE 6°720L Le HIL T'Itol 97 OLE ¢°SIOL 97 007 0° L901 1Z 007 c°LTOL 61 007 @°1col 97 HLE (Geraayyt YA €0€ 0°OL0L CG LOE L°6001 (x4 Ole 7° 8001 J6 spueir] qui ainje ainsseilg aainssaig -ieduay, odtiayd y3zty -soujy oo oo NOOCOOCO SO 0 € val ———— wu “uot -eytdtoaI1g jo yunouy €l 8 91 fi AqtTtq -TSTA 06 09 Oot a I9a0g pnot9 %001-0 :yTe 303 ATYyQUOW :a8ezaae ATYQUOW 0OOL Te oelo Oe 0£60 67 STLO 87 0060 LZ 9¢ o0oot GZ 0€L0 42 O€L0 £2 S790 (6 0080 «IZ S160 07 61 81 SILO LE 07/0 89T = x 0020 ST 003s0= 80 WI SE (al Ba » Ocol IL 0€90 ol $290 6 + a S190 8 S790 E 0060 9 S 9 + i o00gso0 =O€ + i ocelo 4 0€80 IT Aytsuequy 4«suotztpuoj awry eq zay.e9M SuT[teAelg ITV 919eL SUOT}EAIASGQ [eITSOTOIOaqa_ ATTeq Obl 22940390 Al2 96 :[e@309 ATYyQUOPW 6°S L gt €°0ZOI LL 6€ :a8ereae ATYIUO_ oe 67 0Sz [eats 9 81 £04 L°LOOL 6 ©) 0OT SS60) = 82 LZ 0c £°6 £ €1 LIZ L°O€0L 0 VG SL 0080 92 09€ a6 IL LI rat @°120l LI 91 07 OOor GZ O€T [BAS [5 vas EL 8°8IOL 8 Oot 00cI VIG €Z (Kb OnE LES 6 IL L08 7° 7Z0l S 4 oor + u o€lo IZ 062 LES Se 9 VARA €°6201 0 VIG 0# 0S60 02 OvE (Gove € Il vAw4 €°SZoL 0 91 06 OOoLT 6. 062 Oy) 8 61 £0€ 0°900T (Ai) 91 os ST80_—s 8 Ol 9°83 8 61 €0L 9°9Z20L 7 91 14 elelene LI OL SI 0SZ 9 Lt val 918 9°2Z0L 0 VAs 0 O€fIL 41 062 TY € IT 97E 0° L201 0 WKG 0 S¥80.—s ET OVE €°6 € (K6 vag 6°0Z01 0 WE 0” SSl0-—s 2 IT 062 Gul OL €7 OIL T°2rol 0 91 0 0060 ~=—OOL 6 8 002 Cad) Il vat €0€ ¢°ZIOl 0 9T 0 oczo iL 09€ (am) Il 91 977 8° 8I0L 0 97 0 St80 9 OVE eS (as €7 LIZ T° Itol 61 A GZ 0080 S 08I [Ets (al IZ UE f° 0zOL 0 WK6 0S 0060 «= OL 9°€ 7 S°8 0°?I E 8I L0Z 0°0€0L 0 97 OL ooso =O € c 062 LES (4 s°9 S°6 8 SI v AG é°LTOl 0 Che 0 0€lo I Yod (Nenzy) des/m 9, oy an je Jo spuei] qu wo ‘uot wy oh Ajtsuaqul suotjztpuop amity Aeg Voda uolz paedg jutog aanqe aainye aanze ainje aimssaig einsseaig -eqIdtse1g AQI[Iq JaAog aq.eamM A AM -991I¢ putm aq -szedmay -1zadway -1adway -1admay otaayd jo juNowy -ISTA pnot9 SurT[Teaaig puIqM = pueT qind = ating AoT = yBTH -Souy %001-0 puey 22M Aaq NN eae ee aR ee Oe ee ees clv PTdeL SUOTJeATaSGQ TeITSOTOIOa}aW ATTe Obl AJequaaoN Al13 >cteml 09€ 002 09€ OL 002 002 09€ OL 0SZ 0S 0Sé 0SZ 0SZ Ove OzE 0zE 0sz 0SZ (N anzz) wot -2aITq put pueyT das /w paads putA puey Jo qutog aq Jo oinye -Jadway, qing 79M Jo ainye -iaduway, qing Aug € ral == See ol O18 o's cl ras CaL= tS £09 oC ed) OcL (an4 0°OL £02 E26= 8°21 00% 9°S 9°OL Ole Gac- 0°Or 00% 6°8 ama €0€ 87 0°ST £0€ 9°0- €°8 LOE o°s UY AL 7C eel €°8t £0€ 0°OL 0°02 LOE cS 0°ST 00% (Ee gil Ole (E\ 9°OL 717 o°s €°81 9 E290 00% 6'€ 8°CL OIt Jo Jo spuery, ainye ainze aanssaig -Jadway -i1adwaj, MOT 43TH c°0coL I°STOL T°€tol L°orol S°9TOl €°7col 8° 9€0L 8° LIOL @°0col L° LOOT am gains 6°?zor 6° T20l EeLor S°9T0L c°ccol €°9c0L L°O€ot 6° 1201 9° €ZOL qui ainssaig otzayd -souqy wrvyrwaro oOo o owroo oocoo wu “uot -eytdtoaI1g jo qunowy SuoT}eAIasSqg [eoTsOTOTOa qa AT Ted O86I Jequiedaq ELV 9T9eL 91 61 MON OO Td 92 92 91 LZ UD] AATITG -TSTA :[Te 303 ATYyQuoy oS :a8ezaae ATyqUOL Oot oocr =itTEe 06 M OOIT O€ oot + a S70OL 62 82 LZ 97 SZ oot + d (OS AG oor = u O160 £2 GZ 0080 7 Iz j 0z 0 Sz8o0.—s«éOT. 0 0760 =8I LT oot + 4 sts0)—s OL 04 0€60 ST val €L 0 = a o€L0 =a 0v stg0.—osdT Oot -/+ w/a 0080 =O os o€80 46 SZ = a Ssts0. 8 L 9 09 ocso 30S 0 0060 0 sts0 OE 09 0080 =—@ 0 soor =o 9 Kytsuaquy 4 suotztpuojp owty Aeg 12A09 1ay.eaM pnot9 Sut[TeAaig %001-0 Al14 APPENDIX B: WAVE DATA The wave data are summarized in the following forms: a. Ke) | Gage histories. Table Bl includes information about the gage, gage installation, and major interruptions in the data collec- tion. Short interruptions in the operational status of the gage are not mentioned. Time histories. All significant wave height and peak spectral wave period values are plotted as a function of the time through- out the year (see Figures Bl, B4, B7, B10, and B13). So that the sequence of the data can be followed easily, solid lines connect consecutive data points for times when there is a gap smaller than 24 hours between observations. Annual, seasonal, and monthly maxima, mean, and standard deviations of significant height and peak period. Mean signifi- cant wave height and standard deviation, mean peak wave period and standard deviation, and the extreme significant heights are listed in Tables B2, B6, B10, B14, and B18. Also included is the total number of observations obtained; at four observations per day, the maximum number of observations per month (based on a 30-day month) is 120. Frequently during 1980 the backup re- corder was used and only two observations per day were recorded (except during storms and special events), or 60 observations during a 30-day month. Maxium, mean, and standard deviations of Significant height and peak period. The data presented in the tables described above are also graphed (see Figures B2, B5, B8, Bll, and B14) for each month and for the year. The standard deviations are presented as "T" bars originating at the mean value and extending to the mean plus one standard deviation value. The extreme values are plotted above. No extreme period values are presented. Joint distribution functions of significant height versus peak period. Joint distribution tables are presented for 1980 (Tables B3, B7, Bll, B15, and B19) and for each season (Ta- bles B4, B8, B12, B16, and B21). Each table gives the frequency (in parts per 1000) for which the significant height and peak period were within the specified intervals; these values can be converted to percent by dividing by 10. Marginal totals are also included. The row labeled "Total" gives the total numer of observations out of 1000 which fell within each specified peak period interval. The column "Total" gives the number of observations out of 1000 which fell within each specified significant height interval. Annual and seasonal cumulative distributions of significant wave height. For each gage, annual and seasonal significant wave height distributions are plotted in cumulative form (see Figures B3, B6, B9, B12, and B15). Bl Persistence of significant wave heights. Tables B5, B9, B13, B17, and B22 show the number of times throughout the year that the specified wave height was equaled or exceeded at least once during each day of the duration (consecutive days) indicated. For example, for Gage 620, the Waverider located 3 km from shore, wave heights equaled or exceeded 0.5 m 45 times for at least 1 day; 39 times for at least 2 days; 30 times for at least 3 days; etc. Therefore, on 6 occasions one would expect the height to have equaled or exceeded 0.5 m for 1 day exactly; on 9 occasions for 2 days; on 3 occasions, 3 days; etc. Note that the height exceeded 1 m 48 times for 1 day or longer, while heights exceeded 0.5 m only 45 times for this same duration. This occurred because the longer durations of lower waves may be interspersed with shorter, but more frequent, intervals of higher waves. For example, the one time that wave heights exceeded 0.5 m for 29 days may represent 2 or 3 times that the height exceeded 1 m. B2 “0861 Jaquacaq y8nozy, Azenuer 8uTInp uayeq saTtyoad azatd wo1rz yqdep uetpay yy *Aaains ITzVaWAYAeG OSI 1940990 WoIF pauTwiajap yydeq yx % atqeottdde jou = yN :9390N 9°0 ¥9°0 wy ‘vt0ys wor aoueyst( (panutjuo)) os6t ime 2 OL silatyttdwe aiTm snonutjuod 78 ee 46 pesewep suru ysty og6l Ime € BL6T AON = Mu0S,S70SL x NuS,OLTo9€ - qoyheg “2 “N ‘Mong “(uaatg saqeutp100) Fo GNA W 6S) etd WAI UO 0O+61 wotze3s “(Gz9 “ON adeg) AoTAeg pug tatd uoTJeT[eISUT MON O86 8ny ZIT yoraq uo puno} Aonq - aIn[tey Burr0o Obl UNG ZI O86 FEN EL watqoid astou/iatyttdwy Og61 IEW S O86l IRN 72 watqoad astou/ratyttdwy 0861 dad 72 O86 49d ZI wat qoid Jaqyaworeaytaose L snonut quo) VN astou/itatyrtdwy 0g6l qed I 8L6L AON ML 970SL x NT ITo9€ - Aong “ON “Mong ‘aud “(OT9 ‘ON 9829) Japtzeaem ar0ysieay aioys wolj wy 9 Japti9aeM 61 snonutquo) 3utiojztuow uesag O86 29d I Ja[UT u08e19 AiesU punoj - Jau ut Kong 3y8ned tapMerL O86l AON ZZ OBL IML 9 SQTUOI}IeTa Jazauwiolayaoje 281 snonutquo9 YN pasewep SuruzystyT og6l IML € 8L6L AON Ai7'70SL x Ni LTLo9€ - Song “7 “N “ONG “aud “(0729 “ON 29eD) JoptiaremM a10Y4SFIO ysw Tw [su “uw im uotjeue[dxq uot}ze19d9 uotze1adg Sa}euTp100) “"eseg yo adh, yidoq asuey yqsuey dodoig jo dadoig jo 19 eM a3e9 a8e9 jo pug Sutuutsag 0861 10F SatIOYSTH aden aaeK [ld 91qeL B3 ‘w 672 ‘yasueT tatTg 4 “0861 Jequacsaq 03 Arenuer Wory Uayeq sazTtyoid zatd worz yjdap uetpayy xy (paqeutwisy uotzeTTeysuT a3e3) pettey Jaonpsuety, Og6l 4ON 72 O86T IML IT (aatd jo apts yqiou ZuG.209) Zaonpsuelsy aitM snonutjuo0d uo) 1°0 GaS 7 o= 92 pegewep suruqystyT og6l Tr € S960 The M.9€oSL x NiGSoSE - Jojheg "O"N “PeH sen | Jatd surysty Sajyjauuer “(ZIL “ON a3e5) aotAeg peoq sden os6t ime Z slatyttdwe pegewep ButuyystyT og6l IML 0861 99d 42 orl 07 9° I- s'8 pagueys y38uayt a8eg = 6 GAA YZ ~=—OBET UPL BI od wa [qoid a1Tm snonutjuod (arn) Sain 9a 0= QoL astou/aaryrttdwy ogel uer 9 8L61 AON MuOS.S70SL & NutS.OTo9E - zoyheg "DN ‘yond “(UaATO SazeUuTpIOOD JO INA WEST) Fatg ddd uo Oz+9 wot eIg “(S19 “ON 98eD) AO{Aeg ar0ysIeON uy fosoyg psu Tw “Tsu fw w uoljeue[dxy “uo1qe10dg uotqeiodg Sa }eutp100) ase9 yo adky worj yqdaq osuey y3suey tadoig jo dadoig jo aoueqstg 1372 age9 a3e9 jo pug Sutuut3eg (papntouog) 1a alqeL B4 PERIOD, SEC HEIGHT, M LH aj fab da ir JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Nu Wo & WwW 1 Figu a poe time history of ae eight and for the offshore Waveride ae ae No oe OLE 990 92S 8°C Sel 8°0 Ul 990-290 ISI dag (er4 6°Z €°8 €°0 £20 das-[ne Z9L ady [ee 9°72 hey! €°0 8°0 unc-idy 781 Tey 9°€ Ese 8°83 9°0 el Jep-uer yeuoseas L08 290 9°S 6°7 I°8 9°0 0.0 yenuuy III 82 9°S O'€ 9°L o'r er 2aq 78 Il GAC (aa 6 6°9 SO o'r AON LIL GZ 0°47 ES c°8 9°0 O'T 290 847 0€ 0°72 O°€ 8°8 7°0 3°0 das 0S LI c‘t 7G 0°38 z°0 9°0 any ES 8z 9°T O°€ 0°8 €°0 9°0 rae 8€ II Gel cl 6°9 €°0 L°0 une 6S if Tis 9°Z 6°9 €°0 L°0 Aew G9 i 122 Ge c’8 €°0 6°0 ady 79 €L 9°€ 8° 0°OL £20 eo rey 84 Ol €-¢ o°€ Gg S°0 I'l qed GE 91 610 g°€ c8 ED Cr uer AT YQUOR suotjeAsrasqo a7eq w 4y48Tayq das ‘potiag das ‘potieg w %4y3TOH w Qy8ToH Jaquny QWIITXY uoTzetasgg ueopl uot elaAag ueoj pazepueqs pzepueqs 029 “ON 98e5 TOF SOTISTIEIS SAM OZ6I ZH PL4eL B6 Significant Wave Height (m) Peak Period (s) Jan ® Extreme Mean + | Std Dev Mean Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month a. Significant wave height 1980 Mean + | Std. Dev. Mean Jan Feb Mor Apr May Jun Jul Aug Sep Oct Nov Dec Month b. Peak wave period Figure B2. 1980 mean, extreme, and standard deviations of significant wave height and peak wave period for gage No. 620 B7 C) € € $s v tet = 6 98 tut) 06 eee SED Get set 8s ez 8 qW40L 2 ° ° ° t o v ® ° ° ° ° ° ° ° ° ° waLvawd = @ ° e ° e ° ° ° ° ° e e ° e ° ° ° 66° ps b ¢ ° ° ° ° ° ° t ° ° ° @ ° ° e ° ° Br°v = v ° ° ° e ° t ° 2 ° 14 ° ° ° ° e ° 66°E — 8 ° ° ° ° e t e t ° 9g eo ° e e ° ° 6y°E SS €t ° e e r= ° V2 ° v é t e e e o ° °o @6°2 a 9v J : 9 : 8 t § v S é et 2 id $ ° 6¥°2 - [333 : : : 2 : et t ry 9% St 6 62 st 2 s ¢ @6°T = eee : g : 6 t ge v e2 ee 6 at 2b ev 92 2 ¢ 6r°T - Ory : : t 6% 2 22 123 ty es Ett ee av €9 92 ot ry 66° = vEt : 2 e TS t 92 % 9 st ey et 9 8 » 2 t 6b° = BOND] 6°91 6°ST GPT G°ET 6°2T GIS 6°@t 66 6°8 G6°L 69 6S 6°¥ BE G62 ~e°2T -@°9T -@°ST -O°bT -@°ET -0°23 -O@°TT -O°@T -0°6 -O°B -O°L -@°9 -O°S -O°H -O°E -0°O WLOL ($@N093S)G01N3d ( SMS3LSu) 4HOT SA G@OIY3d GNY LHOIZH 40 (@TX)ZONSUUNISO INSOIUSd oy ei ee eee nl 0Z9 ‘ON 2385 TOF pOTieg Yea snsr39A qusTay yUedTFIUSTS FO UOTINGTAISTG JUTOL [enuuy O86l cd eTdeL B8 HEIGHT (METERS) ‘ome Figure B3. 10 10 PERCENT GREATER THAN INDICATED 1 JAN-MAR 80 APR-JUN 80 JUL-SEP 80 OCT-DEC 80 ANNUAL 80 == Annual and seasonal distribution of significant wave height for gage No. 620 B9 ¥§ VLOL WLOL YIONO1 6°9T 6°ST 6°pt —O°LT -O°S9T -O°ST -O°HT -@ ee as YZON01 6°93 -@°2t -O°9t (penutjuo)) e ° e e e 9 ° e e ° e e e e e 2 et ‘ 9 9 et 2 et Z 9 : i 9 2 ° £ 9 $2 te et 6y te te 9 s se q 89 e 9S 9S edt se eg 89 gs se = = z 9 io x et vd es 9 9 et : 6°et -2t 6°33 6°Ot B66 6°8 6°L B69 6°S 6h B°E "ET -O°eT -O°TT -@°eT -@°6 -O°S -O°L -0°S -O°S -O°d ($0N093S)G01u3d GOLU3d GNY LHOISH JO (@TX)SONSUBNIIO LNSIWad NAL=8d¥ -T1YNOSYIS ® cot @ @6t e Ett oer Ser de cot 8st 6y ot e ° e ] e e ° s ° e ° e e e e ° ° o ° ° sg °° ° ° ° ° e a4 ° ot ° S ] ° oe e ° e @ - de 2 22 91 tt s s tt 133 2 : rf €€ - de % 13 6¢ tt S Ey 9% * ¥ = ee 8 28 x 9S ep 9T 13 ee e9 ee Ss : Ss : 13) ° 22 ee ee a3 de te 9t $s ° g ° de ° § e €€ e e e @ e 6°St G°ot GES 6°2T 6°TS 6°et 6°6 6°8 6°2 6°9 6°S 6°P 6°E -O°ST -O@°ht -@°ET -O°eT -O°TT -@°@r -@°6 -@°S -@°L -O8°9 -O°S -O°P ( SGNO0I3S ) COI wad 3WSToH JUeITFIUSTS Fo SuOTINGTaqSTg JUTOF TeUOSeaS OgéI @OIY3d GNY LHVIZH 40 (OTX)ZINSWYUNIOO INIIWSd BUW-NVE -TWNOSY3S ! @ ° ” ® WLOL a WALvayo - @0°S 66°r - OS’ < 6y°b - 60°r 5 66°E - @S°E cS By°E - O@°E i 66°2 - es°2 e 6y°2 - e0°2 ° 66°T - O9°s : 6h°T - GO°T % 66° - @S° 6y° - @0°@ 6°e -0°e@ (S83L3M) LHOT 3H j=) ce © WLOL -Q ° BILEBWD - 06°S : 66° - 6S°b e. 6y°v - 00° sf 66°E - OS°E i Bh°E - 00°C a 66°2e - eS°2 i 6y°2 - 60°2 © 66°T - OS°3 fe 6r°t - 80°T S 66° - @S° 6y° = - @0°e 6°e -0°e@ ($83.13) LHS 13H 029 “ON a8e5 TOF potiog yeag snsiaf 7€@ 9TdeL Table B4 (Concluded) JUL-SEP SEASONAL- PERCENT OCCURRENCE (X1@) OF HEIGHT AND PERIOD TOTAL PERIOD( SECONDS ) HEIGHT (METERS ) 16.9 LONGER 1S.@- 16.@- 17.@- is 13.@- 14.e- 13.9 14.9 9.0- 10.0- 9.9 16.9 ONG ~- ©C@OGC@ aoov 3-0 eee eee eo oo o@® Me 6 © 6 © 6 oo ow of eee eee eo oo o@® WMM -2eecre ee un~ & ee ee ee co ow oe o@® WOOF 2 c © © 0 0 © o® ues & eee eee er ee o o® YT ee yy ~u ~ er -“ 2 QQAQ®QQQQaQaa eee ee eaosse eee eoerececeece AsadnaweSs SM 5 eee e L AN [oe TT Tee) @ =xanunnvTw Bll @) OF HEIGHT AND PERIOD OCT-DEC SEASONAL- OCCURRENCE (x3 PERCENT TOTAL PERIOD( SECONDS ) HEIGHT (METERS ) 16.9 LONGER 16.@- 17.0- 11.0- 12.@- 13.@- 14.@- 15.@- 11.9 12.9 13.9 14.9 15.9 9.9 10.9 9.0- 10.0- VQ 8.0- 7.9 BETBELAeree Tow RMU ee eee eee oo o® Meee ee oe co o of WM ee oe 0 6 oo o@® MDW > ee oo oo om WMWOM > -M « o omMwM « 1”) mReanM ee of 0 ow = w eaece Ah OS 4 i) iy) ry eA La a ~ MWMRWWMM o « og MOaw Ww « oO born RC AU ™ Q ° v BERS yg ~ WEMM - 2 oo o o o ine ¢ = PMARM ce oe oo og 8 B al ha air eM ee eo 0 0 ow ow = ~ @ = AQAQQQQQARE PEt St tt tt eecee cece ee AMUUNAMT?T 000000000 0 0 e& < oO s3sasszazss" © AnUNMMTTH *skep aATyNdasuOD Fo aaqunu patytoeds ay 103 Aep e aou0 yseaT 7e papascx%e Sem y8tay aaeM YuRITFTUSTS UdATS ay} TeaA ay. BuUTInp sat, Jo JaquNN yx ee ee SS SS ee 4 0°4 ”) Gre T tees Ove Ie Doe 28 Sz I lo 0°2 I. % ”) 8 9 9€ crE I 4 € 4 9 @ %@ ze BF O'l ‘oer Z & 4 Ss. 6. <4 6 Ol UL “i Ol Iede oc 66> SP S‘0 WC Ge 82 eos SE ne C7. ee OEE OT «SEE St ttt Ol. 68 8 Ge ee skeq 9AT ndasu0) papacoxy 243TH 0Z9 “ON 285 TOF SZYStTaHY aAeM QUeITFTUSTS OBGl FO y90USzSTSIIg Ga 9T9®L B12 PERIOD, SEC HEIGHT, M -_ Nw (eA) oO -_ (=) Nu wo £& WM JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Figure B4. 1980 time history of significant wave height and period for the nearshore Waverider (gage No. 610) B13 O€E 390 8°€ O°€e G83 9°0 o'r 99q-290 gL dag S71 GS 8°8 €°0 L°0 dag-[nc ZLI ady (ard 9°Z o3 €°0 4°0 unp-ady 6cL uec WJeAS [ENG 9°6 8°0 HT zeyj-uec yTeuoseas LOL 290 8°E€ 8° L°8 9°0 6°0 yTenuuy 901 62 (SS EAS 7°83 (EXD) o'r aq 6IT 57 Gc Le 9°8 s°0 O°1 - AON SOL GZ 3°€ SiG 9°8 9°0 6°0 320 ey 0€ gI 9°Z 8°6 €°0 Lo dag €€ Ge GT ct GL €°0 9°0 any e7ep ON Tne 61 4 8°0 9°T S°9 20 S°0 une 18 I 9°T 9°Z 6°L €°0 9°0 Aey GL I EZ 9°Z Z°6 4°0 3°0 ady 9S Z 5°€ 9°Z E70t L°0 eT rey LI lid exe 0°z 6°6 S‘0 6°0 qed 9S oI y°€ 1EG L’°8 8°0 9'T ue AT YWO_ suoTqeArasgo a7eq w 443TH das ‘potiag des ‘potieg w *34sTay w “4y48toy Jaquny QW9I4XY uotjzetasgg ueoyq uoT}etasgg ueoy piepueqys piepueqs O19 “ON 98e9 TOF SOTISTIEIS FAeM OBET 9a PTqIeL B14 Significant Wave Height (m) Peak Period (s) X Extreme 5 Mean + | Std. Dev. | Mean 4 x X X x X 3 X i : 2 x: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec] 1980 Month a. Significant wave height 14 I Mean + | Std. Dev. Jon Feb Mar Apr May Jun Jul Aug Sep Oct Nov’ Dec} 1980 Month b. Peak wave period Figure B5. 1980 mean, extreme, and standard deviations of significant wave height and peak wave period for gage No. 610 B15 WLOL 0 4 € 69 2 @ 6t 22% str set 18 Get eS yh ft ° e ° e ° e e t e ° ° e ° ° ° e e ° 15 ° 9 ° Ae t y ° e ° e e ° ° e € ° ag ° 9g 9 zd 4 t e e e : : ety a ew EY ee EB eS : : : : : - @t tr j-er °° §* 8 8s ef SF 9 | & : ; : - g tt §@ 9 € tt te te s€ 82 e€ 3% é t+ ce € € #82 8 8 2 tt S2 wy Lo CC q 9 ° 2 S$ ve » sf t€ s8 8 € E * : y30N01 6°93 6ST G'hT GET Get G6°ts GO 66 68 6s G69 6S BY GE ~e'et -@°9T -@°ST -O°vT -@'ES -C°2t -O°TT -O°QT -O°6 -@°S -O'L -O°9 -O°S -O'H -O°E ($GN0935 )d01u3d GOIN3d GNY LHOIZH JO (OTX)JONAUWNIIG INIIVSd OL9 ‘ON 28e9 TOF pOTtag Yeaq snsr9A Jystoy yuUeITFTUSsTS Fo uoTINqraystg yuTor Tenuuy Og6l L@ PTIeL eM © 0 6 oe 0 0 8 OM WLOL YILVSYO - 00°S 66° - 68°” Bh°y - 60°r 68°E - OS°E 6r°E - 60°E 66°2 - @S'2 6y°2 - CO°2 66° - OS't 6r°t - 6O°t 66° - @S° 6y° - 60°@ (S¥U3L3M) LHOISH B16 HEIGHT (METERS) 3.0 4.0 5.0 6.0 7.0 2.0 1.0 0.0 ah Figure B6. i 10° 10 PERCENT GREATER THAN INDICATED JAN-MAR 80 APR-JUN 80 JUL-SEP 80 OCT-DEC 80 ANNUAL 80 Annual and seasonal distribution of significant wave height for gage No. 610 B17 RAGUNSOCOVS aM on WLOL WLOL coer eee ee eo o® a ey) YZINO1 6°9T -e°2dt -e°9 ¢ 8 Y39NOT 6°93 -e@°2t -0°9 -« (penutjuo)) 2 e e e et e e e e ° ° ° ° e ° 9 ° 9 e ° ° 9 ° et e e @ : Z > et i : et dt Ee zt et ey 9 s! ty in ty © Ott 8s vet ty 79 se 8s dt ° dt . €e i 9 8s Set €2 9 9 © o 6°St 6°ot BET Geet 6°ts 6°et 6°6 6°8 6°L 6°9 6°S 6° 6°E -0°ST -O°ot -@°ET -O°ST -O°TT -@°et -@°6 -@°S -@°L -O°S -O°S -O°R -O°E (SGN0I93S ) GOI ¥3d GOIY3d GNY LHDIZH 30 (@TX)ZINIVBNIIO LNIIWId NNF-UdY -T1YNOSY3S 9 6et @ vee e vot Bt vet 9S €6 €9 93 8 : 8 : as . 8 8 : ° ° ; . ® 9t i 8 y ee 9t 9t 8 : : © . 4 te re gt . 9t 9T 8 8 . . ‘ £ s ee = 6E 2 TE ee €e 8 ee 8 . - S te ° S38 ; dp te €e 8 TE 6E 9t 5 y 4 ‘ i> Ec te TE €e 9t 6E 9} 2 : * i 6E ‘ 9% ee ce 8 z s i 6°St 6°vt G°ES 6°et B°TT 6°et 6°6 6°8 6°L 6°9 86°S 6°R B6B°E -O°ST -O°Pt -@°EL -@°2T -O°TT -@°@T -@°6 -@°B -@°L -@°S -@°S -O°H -@°E (SQN093S )d01¥30 GOIU3d GNY LHOISH JO (OTX)ZONINBNIIO LNIIU3d B-NeF = -IONOSHIS eee ee 0 0 0 oo o@® 6°2 -6°e@ coco ec ee oo o@ WLOL YALY3NS - 60°S 66°o - 0S°h 6y’r - C0°r 66°E - OS°E 6y°e - G6°E 66°2 - @S’°e 6r°e - ee°e 66°% - eS°t 6y°t - 6O°t 66° - @S° 6p° —- 60°O@ (S¥3L3M) LHDT3H WLOL BILVBN - @0°S 66° - OS’ 6r°r - 68°r 66°E - OS°E 6h°E - BO°E 66°e - OS'2 6y'°2 - G02 66°3 - eS°t 6r°t - eO't 66° - @S° 6y° —- 60°0 ($¥83L3W) LHOT 3H OL9 ‘ON 98e5 TOF poti9g Yeog snsiap qYystay JUeITFTUSTS FO SuOTINqTaysTG JUTOF TeUOSe|g OZ6T 8d 91deL B18 . ) st 9 tS 8p ec ey at t v8 vst 96 6et at 3 ey et -) ° o ° e ° e ° ° e ° J e e ° e e ° ° e e ° ° e ° ° ° e e ° oe > € e e e ° e e ° € ° ° ° ° ° ° e st e 1) e ° ° 8 ° € °e 9 7 e U} ° e Te e . e e e ° e € 9 6 ° € ° e e be g g . € € is € : 9 € € € hi is ect 3 ‘ 6 ve € Zi a 6 et ve 6E 6 € 2 ete ° g € € et et GE 9 (x ce ey SE et Z cS€ % € 9 st 9 6 8t 8y 6E Sy ve 6E ez de es eee 6 et ‘. te et 2p 6 CE Bt es te € . i : B3IN01 6°9b 6°ST 6°>s 6°ET 6°es 6°tt 6°eTt 6°6 6°8 6°e 6°9 6°S 8°» 6°E -O°L3 -O°ST -O°ST -O°wt -@°ET -@°2T -@°Ts -6°@T -@°6 -O@°S -O@°L -@°9 -@°S -O°r -@°E WALL (SdNO093S )GOlv3ad GOI¥3d GNY LHOI3BH 40 (@TX)3JON3YINIIO INIOWIA 930-190 -TYNOSY3S , i a od e. a eee es Bit . : © et . et 2 ie ° 2 et €s et ey 2 2€9 © © i €s i 62 x 62 eet tte ES g2 et 92 . 602 3 : ° ge 2 et * 6E Set ey : et : : B30N01 6°9T 6°ST G6°Hs GB°ET 6°e2t 6°tt 6°el 6°6 6°8 6°2 6°93 6°S 6°D 6°E —O°LT -@°ST -@°ST -@°bt -@°ES -@°2T -O°sT -8°@T -@°6 -@°S -e@°2 -9°9 -0°S -O°r -@°E WLOL (S@N093S)G01YN3ad GOIU3d GNY LHOI3H 30 (@1x)3Z0N3NNNDI0 4IN3983d d3S-1Nf -T¥NOSY3S TO ee ee ccc oe ow ey | (Pepny{suc05) gg etqey oo ee eee PPL PT Hs Hs 3 Se =qjxanunnmnnms ( S83L3) LHO13H B19 *skep aATyNdasuoa jo Jaqumu patjtsads ay Joy Aep e adu0 yseayT ye papaaoxe sem YysTay aaem queostjtusts uaaT3 ay} AJeah ay. B8uTInp saw Jo Jaqumy y (4 fe Sy Sl. 21 OL 6°E 6°2 —O°LT -O°9T -O°SE -e°bT -@-EyT -®°2Tt -O°TT —O°0T -@°6 -6°B -@°2 -0°9 -O°S -@'yp “e°E -0°e WLOL (SENO093S ) dOIY3d (S$831L3M) LHDI3H @O1Y3d GNY LHDIZBH 40 (@TX) 3ONBYYNIDO 4N3DY3d d3S-INf -TeNOSYaS (pepn[sueg) Zig aTqer B27 zaqunu patyroeds ayy 103 Aep e a0U0 yseaT 3e pepsedxa sem IY Stay SAeM 4UeDITJTUSTS UaATZ ayy ea 94. BUTINp SeWT Fo z9quMN x *sAep aATyNIasUOD Fo i o'4 I GG 4 O'€ I € 8 SZ (A eee! OrZ aes i "GL 9z Cur [ese oe 4 9.0L 61 s6%2 €Y O°l 4 e ) 9 Love 36. OL TE BEL 2a, Zee Se. 0€ - £6- 44 S*0 OGarGU mee ia 00 GG she 0 ce 1 Oe OTOL OR SE Eh cL fide le ey Se ee es a skeq eat noesu0) pape2sdxyq qy8teH GZ9 ON a3e5 JOy SQUSTOH SAeM WEITFTUSTS QYbI FO €Td 91921 ydIUIYSTSI9ag * B28 HEIGHT, M PERIOD, SEC 7 | i a , i! JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Figure B10. 1980 time history of significant wave height and period for the nearshore Baylor (gage No. 615) B29 (bss 190 Pa 9°€ 7°83 C0 9°0 3ag-190 891 Sue ila 9°€ €°8 z°0 S°0 dag-Tn¢ 91Z idy et Gale 0°8 Ga0 S‘0 unp-ady 641 rey Cz G’€ 9°83 S’0 6°0 Jey-uer yeuoseas 0L8 rey Cag GE €°8 €°0 9°0 Tenuuy Z0L 0€ C7 Les ied €°0 9°0 92d SII vid eal Lg (it €°0 9°0 AON Ge GZ Lt Ogee 16 €°0 9°0 320 nh 0€ [1 5° € €°OL oO 9°0 dag 8S Ce 8°0 Geg 6°L 10 7°0 any 89 LZ bet Ce Ga G0 S*0 rae LS GZ 6°0 Cx 9°9 70 S°0 une L8 I reall Ge 4°83 G20 S°0 Aew Gi 1 sea! ous Eee z‘0 9°0 ady LL € e¢ BSS S*6 S'0 6°0 1ey ey LI Lat 6° E23 7°0 6°0 qed 62 81 0° 8°72 8°9 S'0 6°0 ue AT YQUOY suotjeArosqg 27eq w 6 zYsTaH Sas ‘potiag das ‘potiag w ‘YysToH w ‘ys Toy Joaquny QWIIXY uOTIeTAII ued uOT Je TAI uel paepueqs paepueys G19 “ON ade) TOF SOTISTIEIS DAeM OB6T yld P19eL B30 Significant Wave Height (m) Peak Period (s ) x Extreme 615 I Mean + | Std Dev Mean Jan Feb Mor Apr May Jun Jul Aug Sep Oct Nov Dec} 1980 Overall Month Year a. Significant wave height 615 | Mean + | Std Dev Mean Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec} 1980 Month b. Peak wave period mean and standard deviation Figure Bll. 1980 mean, extreme, and standard deviation of significant wave height and peak wave period for gage No. 615 B31 t 8t é vot =v 88 Lt 26 SL 9€t 69S €6 tsi = 6B 6e é WLOL e ° ° ° ° e ° ° ° ° ° ° ry e ° ° e waLeaye9 = @e°s C) ° ° ° ° ° ° ° e ° ° ° ° ° ° ° ° 6B°v - OS’ C) e ° ° ° ° ° ° ° ° ° ° ° e ° ° ° 6y°R = CO°r e ° ° ° ° e ° e ° ° ° ° ° ° ° ° ° 66°E - OS°E C) e ° ° ° ° ° ° ° ° ° ° ° ° ° ° ° By°E - CO°E @ ° ° ° ° ° ° ° ° ° ° e ° ° ° ° ° 68°2 - eS°2 € ° e ° 2 ° t ° ° ° ° ° ° e ° ° ° 6e°sS - ee°2 6t . : 9 3 t t € z s t 2 : y 66°T - OS°t Lot s 2 € ot 8 lal € ot s tt 8 9t et 4 t e 6y°T - e0°s ees : e t ee e €e 9 6y 9€ ts 62 2s set €9 te s 66° - @S° S9E t vt € Sv vt 6y re 92 ve 69 Cs gt ee ve é 2 6y° - 60°@ YZ9NO1 6°9T 6°ST G6°hHt GES Get 6°tt 6°et 66 6°83 6°L 6°9 6°S 6% GE 6°2 -@°239N3YBNII0 LNIONId 930-190 -IwNoswas @ . ee ert 18 ee oo fs eS YS OG LEN TET Se b4 : , . : . . : : : : : : ° : : 5 . : : : : ° : ° : : : : : : : Q@ e ° oJ ° ° e e ° e e ° e ° ° ° t) ° ° e e e e e ° ° ° e ° e ° e D4 ° . : : ° ° j . j : . : : . : Q@ ° ° ° e ° e e ° ° e e ° ° e e Q ° ° e ° e ° e ° ° e ° e ° e ° GE ° . e e e ° e ° ° gt et ° e e e LTb : : : so: vein ft st #2 S€ @€ 2 e€8 te v2 9s5 : ee ke eo ey e@€ TET 2 8 65 @9 at BIONO] G.9l G-St Girl GE Get 6°It Gel 66 68 62 69 6S 6 BE ~“O°LT -O°9T -O°ST -@°bT -O'ET -Ovet -O'IT -@°@T -@'6 -0°8 -6°L -0°9 -0°S O°» -6°E 1104 (SQN093S)G0Iuad GOIY3d ANY LHOIZN 30 (OTX)IONSYYNIIO ANBIVId d3S-INf -TWNOSYRS -6°€ we WW ee ee eo 0 © 0 = 6°e -0°e@ a a rey) Ne VLOL YaLvaN8 - 60°S 66°h - OS’ 6y°y - C0°r 66°E - @S°E 6v°E - @O°E 66°2 - es°2 6v°e - @9°2 66°T - @S°t 8y°t - CO's 66° - @S° 6y° - @0°e@ (S83L3W) LHOI3SH WLOL B3L0399 - 00°S 66°h - OS’ Br’ - 80° 66°E - @S°E Br°E - CO°E 66°e - eS’°2 6v°e - C0°2 66° - eS°t 6r°t - CO°t 66° - @6S° 6b° - 60°e ($8313) LHOI 3H (PSPNTIU0D) Gig eTqeL B35 *sAep aaATyndasuod Jo aaqumu patjtoeds ay tof Aep e adu0 yseaT 3e papeadx%e sem qyZtay aaem quedTyTUsTS UaATS ayq A1eaA ayy BUTINp sawT] Fo JaqumN y 7 s’€ ove Gz L. 2 0-2 - 972201 ia I 1 Le Uh “Shen 97 o'l I Counce 4 8 Geek 6 sec. 06. thee TS S°0 De 6c Sz Oe cr ene eee ec SOU GO ee OTe GT pie Chan OR 6 ee ON Ge 22 w skeq aAtTyNdasu0) pepaaoxq qy3TeH C19 “ON o3e5 OF SPYSTOH SAM JULITFIUSTS OBGl FO yadU9qSTSIag LT@ 9T92L B36 PERIOD, SEC HEIGHT, M At ‘ hh i At i AP hl q bsisncily tay, ; JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Figure B13. 1980 time history of significant wave height and period for the Nags Head Baylor (gage No. 112) G8Ec 0861 390 €8°C I8°¢ 60°6 17°0 6L°0 O86 AON-ZZ6T UeL aatqepnuny 89€ uer 06°L 0S*Z 47° 6 Se“0 9L°0 6L6L E8E idy EC OE2 97 °6 8e°0 S6°0 8L61 0S8 29d €L'Z 98°7 Z0°6 870 S9°0 LL61 73 390 68°72 [SG 00°6 47° 0 Z3°0 0861 yenuuy 76 ail S6°T iS 9% Z7°8 0S°0 66°0 AON cI GZ E8°c (SY herd L7°6 zS°0 96°0 490 GY 0€ 73°1 OL°Z cl OL L¢-0 08°0 das 19 oC GEL 79°Z 6S°6 LZ°0 z9°0 sny 6S 87 Hee GI°% 00°83 oe 0 69°0 rn¢ tS €l Le Sit 97° L 87°0 CEO unc 78 T 89°T 10°€ Ly°8 8Z°0 €9°0 Ae 89 if 16°L G82 0S°6 €€°0 8L°0 ady 7 7 SAGA I0'€ 10°O 67°0 vila rey €S 97 6/1 69°Z 96°8 9€°0 LO eT qed 6L L1/91 76°T LOZ? 90°6 6€°0 60°T uec SuoTyeAresqg | o7eq)~—Ss I qYSTay ODS “potsadg das ‘potiad w 4y3TOH w %443tey AT QUO Joquny QWIITXY uoTzetAsg uel uot ze lTAdg uel pazepueqs pzepueqs ZIL ‘ON 9885 TOF SOTISTILIS VAeM stad 2T9deL B38 *° 101 t 1) Ve 69 gt set 7192 62h 6 VWiloOl £ Ly S 6°9b= 0°95 ¢ t 6°she 0°sct 1 8 9 ot 6 ct ray o°nl= O°nt t i f a°ghbe O°et ct 6 ge gt 9f g ac2te 0°et t J t n S S ot e°the ort f 9 ot nt 62 6\ H°obe 0°05 7 8 nt gt 62 ee t 6°6 © 0° I ot gt 02 nS Tes & a°e 2 0°S r S nt ot nt nt 2 t a°L © 0% & ) 02 92 ne 92 4°79 = 0°9 if tt chs én ot 6°S = 0°S g ims 72 g 4°n © 0° ¢ ot t a°s = 0°¢ b if Gee aa Oe. 6° = 5021 a° = 0°0 + €5 Et=2b ates TheO0t Ole6 OB Bel 409 92% gen et L£=2 2el bed ($338) (1d) LHOTSH °OTS aoluad ($90 0005 Yad SNOTLVANSSHO NI) GOTe3d SA LHOTAR LNVIISINOTS 30 NOTANSIYisTa ZIL ‘ON 9889 TOF pOtitog Yeog snsi9A Jqstay queoTyIustg Fo WoTynqraystq JuTor Tenuuy Og6l otd 2L4eL B39 Significant Wave Height (m) Peak Period (s ) X Extreme | Mean + | Std. Dev Mean Jon Feb Mor Apr May Jun Jul Aug Sep Oct Nov Dec} 1980 1979 1978 Overall Jan Feb Figure B14. Month Yeor a. Significant wave height | Mean + | Std. Dev. Mean Mor Apr May Jun Jul Aug Sep Oct Nov ODec| 1980 1979 1978 1977 Overall Month Yeor b. Peak wave period mean and standard deviation 1980 mean, extreme, and standard deviation of significant wave height and peak wave period for gage No. 112 B46 *°101 2 ot on S6 295 USe 08k Ih Wil + 0°T2 1 6°0e= 0°02 6°ob= 0°6] 6°ebe 0°aQl 6° Lb= O°Lt g I 9 6 4 6°9b= 0°9T ‘ o°Sb= 0°st b & U7 S 9 ut en 7 6° rhe O°nt ‘ 6°cb= OFF] ¢ Z 8 et el 9€ 9 6ce2be20S et I 2 2 g 6°tb= O°TT ro S fh gt ay oF t 6°0b= O° OF & S ot ud id 9S S 676 "2 0%6 £ et et £2 9S 921 91 6°8@ = 0°98 é Z gt gt oT ee & Qin/e Ostieyh 2 S 7B ie 22 22 é 6°9 = 0°9 é nt 92 9¢ has 6°S = 0°S I et Lt 9 6° = 0°h ‘ 2 9 n 628 2=02¢ & 6°2 = 0°2 (Sisal Sea Haan ( 62° == 020 + Fb &Te2b ectoll Ih=Ol Ul"6 oy wed Leg 92S Gen net tee gh teu (s93S) (144) LHOTISH POTS voluad (So 000) 44g SNUTLVANSSGO Ni) QoTuad SA LHSI39H ANVILSINSDIS 40 NUTian&laasia ZI “ON A8eD TOF potsag yeag snsiaj WTI UeITFTUsTS FO uoTInqraastq TOP (OS6I-LL6L) T1eIdAO Ocd FTGFL B4l Significant Wave Height (m) 4.3 Jan - Mar 184 Apr - Jun 162 Jul - Sep 151 Oct - Dec 311 + X A 0 0.1 0.2 0.5 | 2 5 10 20 50 Probability (Pct) Greater Than Indicated Figure B15. Seasonal distribution of significant wave height for gage No. 112 B42 100 #°101 4+ ¢t Eteel atoll (penutjuo0)) S oF im nie ele nel 9¢1 ot Wink OT 6°9T= N°Qq] 6°Sh= 0°ST S st ne 6 rd S 6°hle N°nt 6°ehbe O°E] ne ne €S 02 gs! OT 6°2le neat 6°tbe nett S ne ne OT S SI 6°0Te 0° OT S st ne gt ot ns S 46°6 = 0° st ne fn ol 6F S 4°R © 0°9 S gs! ot ot S S 4°L = 0°% S 62 AL ng 6t 6°9 = N°9 ot 89 6¢ oT 6°S = 0°S S 62 6°h |= 0° S 4° = N°¢ 6°2 = 0°2 (yee el) Hl § 62 ——=020 Tl-0t 0126) 6-8 gel L-9 9=S Sen het ged Ze] bev ($94s) (14) LHOTIH °OTS anla3d 08 HVW HINNHH) O8 Nv HO4d ANVWAIIS (SAN 9000 dad SNOTIVANSSAN NI) ONTHad SA LHOTIH INVIIGINITS 4M NOTINGTYLSTO ZIL ‘ON 98e5 JOF pOTrag Yeoag snsi9p [cd 9L9eL yYStayyueOTFIUsTS Fo uotyINqTIAASTG JUTOL TeUOSseI|S B43 st nS *°10L + ¢b gteet 2tett tv=<01 O16 (san 0005 6-8 ve ane (peanut zu09) ot gt 0S Let ot gt OT ot ot ot st st ot ne S S S ot S2 S gt ot (14) LHOT3H °OIS HONOYHL O8 Ydv YO4 AYWVWHIIS nee ve vg 9Sn S 62 16s 02 Poreoorer 7700S ° =-NUMITNOYF DS eco soooaoc[3ao ° SCeKNMIANOF DS (sJ4s) gold3id Yad SNUTLVANSSAHO NL) GOTY3d SA LHOIIH INVII4SINOTS 3D NOTINULYLSsta (panutquog) izq FTqeL B44 Tet ese *° 104 + a. North side (to 10 March) 288 b. South side (to 10 Ma FRF profiles for March 1980 (Sheet 1 of 2) DATES 28 FEB 88 4 MAR 88 S MAR 88 7 MAR 8& 18 MAR 88 408 DISTANCE FROM BASELINE CM) rch) 688 608 = eS ro] w £ uJ > 3 2 < 2S [o) _ te coq a au -S lu -19 10 ELEVATION ABOVE MSL (M) ® -10 d. 288 DATES 18 MAR 8& 14 MAR 8& 19 MAR 88 24 MAR 82 420 DISTANCE FROM BASELINE CM) 200 DISTANCE FROM BASELINE (A) South side (10-24 March) Figure C3. North side (10-24 March) DATES 10 MAR 80 14 MAR 80 19 MAR 80 24 MAR 80 400 (Sheet 2 of 2) C5 ELEVATION ABOVE MSL (M1) iss] 10 ELEVATION ABOVE MSL (M) @ wm 0 Nn -10 DATES 24 MAR 88 2 APR 88 11 APR 88 18 APR 88 2S APR 88 288 488 682 DISTANCE FROM BASELINE CM) a. North side DATES 24 MAR 8@ 2 APR 80 11 APR 80 18 APR 80 2S APR 80 200 400 600 DISTANCE FROM BASELINE (fM) b. South side Figure C4. FRF pier profiles for April 1980 10 ELEVATION ABOVE MSL (Mm) © ea] 1 nn -10 @ 200 400 600 DISTANCE FROM BASELINE (M) a. North side ze DATES 25 APR 80 2 MAY 80 10 MAY 80 17 MAY 80 22 MAY 80 wi ELEVATION ABOVE MSL (FM) ©e t nn -10 @ 200 400 600 DISTANCE FROM BASELINE (M) b. South side Figure C5. FRE profiles for May 1980 (7 10 wi ELEVATION ABOVE MSL (Mm) © 1 nm -18 1® nn ELEVATION ABOVE MSL (M) © i) wn -108 DATES 30 MAY 80 16 JUN 80 19 JUN 80 25 JUN 80 30 JUN 80 200 400 DISTANCE FROM BASELINE (M) a. North side DATES 30 MAY 80 16 JUN 80 21 JUN 80 27 JUN 80 30 JUN 80 200 400 DISTANCE FROM BASELINE (fA) b. South side Figure C6. FRF profiles for June 1980 ca 600 600 ELEVATION ABOVE MSL CM) ELEVATION ABOVE MSL CM) 2288 422 628 DISTANCE FROM BASELINE CM) a. North side 2282 428 692 DISTANCE FROM BASELINE CM) b. South side Figure C7. FRF profiles for July 1980 C9 © ELEVATION ABOVE MSL ¢M) a ELEVATION ABOVE MSL (MD a DATES 27 JUL 88 3 AUG 88 {1 AUG 89 18 AUG 89 25 AUG 89 289 420 688 DISTANCE FROM BASELINE CM) a. North side 288 429 688 DISTANCE FROM BASELINE CM) b. South side Figure C8. FRF pier profiles for August 1980 C19 ™ eS =| 2) = lJ a om 28 < Zz fo) A | oe << iu aly -S uJ -12 1%) 229 488 628 DISTANCE FROM BASELINE CM) a. North side 18 mm” =) 5 a) 7) x= uJ ras mo 2 < Zz ro) A tk < iu ayy -S ul 2) 288 428 682 DISTANCE FROM BASELINE CM) b. South side Figure C9. FRF pier profiles for September 1980 Can 18 ™ GS al 2) = lJ re oa 8 << =z fo) ima kK < io Et as lJ -18 10 ELEVATION ABOVE MSL (M) © -10 288 488 6288 DISTANCE FROM BASELINE CM) a. North side 200 400 600 DISTANCE FROM BASELINE (A) b. South side Figure C10. FRF pier profiles for October 1980 ELEVATION ABOVE MSL (MI) ELEVATION ABOVE MSL (fM) Figure Cll. DATES 27 OCT 80 3 NOV 80 20 NOV 8e 200 400 600 DISTANCE FROM BASELINE (fA) a. North side DATES 27 OCT 88 3 NOV 86 1®@ NOU 80 20 NOV 80 26 NOV 80 200 400 600 DISTANCE FROM BASELINE (fA) b. South side FRE pier profiles for November 1980 C13 10 -5 ELEVATION ABOVE MSL (M) -10 10 ELEVATION ABOVE MSL (mM) e 200 400 600 DISTANCE FROM BASELINE (fM) a. North side 200 400 600 DISTANCE FROM BASELINE (MAM) b. South side Figure C12. FRF pier profiles for December 1980 C14 (uotjed0T ToTAeg at0YsitesuU W 68L 2e Uayeq SUOTIeADTS WORIO0G FO apts yynog -q “I"N WONO* 4Y3 DY39 18 69 3NI7 31150Yd YOS NOILBASIS NI SONBHD 930 AON 130 d3S Onb Inf NA ABW Ydd YUN 834 NUP SS 00°681 | {NW )39NbLSIO ONISSIN HLbG >, ‘ MYBNHINIG FHL SI WALBO WLNOZ1YOH mISNeS TWA LOG atO Set ao Avene on enitae cin ae ngs mse On mets ewan ee oe Ll- (CH 2 NOLLYARI3 :07+9 woT}zeqs Jatd) SOTIOISTY UIT], "€LO vansTy apts yqoN “ek “ON \ 18 89 3NI7 3114504d Wo4 NOTLBASIZ NI SONBHD (=) @ D a 930 AON 190 d3S nd Wr NAP AUN Ydd YUN G34 NU SSS SSS SS 00°681 {W )3ZONHLSIO ONISSIN YlbO | MYBHIONIA SHL ST WALYO TWLNOZTYOH TSW SI NALYO-THITLESA~ €- (HW 7 NOILYART3 C15 (OZ+L uotqeys Jatd) W 6IZ 2e Uayey suUOTJeAaTa WORIOG FO SaTIOISTY sWTYL “FIO ainsty “2 NOLLBASTA NI 3ONBHO AHN Ydd SBN 835 NEF apts yyn0g “q apts YyIJION "O°N MONO’ 4Ys 939 “OTN MONO‘ 5H4 9439 ib 69 ANID 311S0Yd YOS NOLLYASIZ NI 3ONBHI 1H 89 3NID 311450Y¥d YOs opel 0861 930 AON 190 43S on’ Ar NAP ABH Ydd YUN 834 NYC 330 AON 190 das on’ TAP Nar L- s- (NW ) NOILYAII2 ’- O0°61z {W )30NULSIO ra) oo" 6tz (NW JZONBLSIO ONISSIN YlbO *, SN ONISSIN BLbO we MYBNHINSG SHL WYBNHIN3E JHL SI NALYO TWLNOZ1YOH ST NML¥O WWLNOZIYOH SW ST WNLWO THOLTLYSA ie sh SI WALUO TWSELY3A | y L- (Wo) NOILHAI13 C16 (O8+L uoTqeqs Jatd) W gezZ ze Usye} SUOTJeAaT|A WOJ}J0G JO SaTIORYSTY JWT] ‘“S{[9Q ean3Ty apts yqnog -q apts yWoN “e “ITN MOO’ 4Y4d D359 SosN ae a* 444 39439 1B 69 3NI7 311450Y¥d YOS NOLLYAZI3 NI JONBHD 1B 89 3NI7 3) ) O¥d YOS NOILHAS13 NI 3ONBH 0861 og6t 930 AON 190 d3S Onb WT NAT AUN Ydd YEN 834 NUP 230 AON 130 d3S ONB INF NAF ABN Ydd YUN 834 NUT SS m |= mi 4 < - D> 4 3 z 5 4 00° 8Ez2 (W )Z9NBLSIO 00° sez (W )3O0NULSIO ONISSIN HLUO +, ONISSIN WiboO *, ‘ ‘ MYBNHINZS JHL MYBNHIN3G BHL SI NN1¥O TWINDZIYOH SI NALYO TWLNOZIYOH ISH SI WNLYO WWOTLY3A ' ASN SI NALYO IWOILY3A - 7 NOILBAR13 tw C17 (00+6 UoTIe4s Jatd) W/Z 3e Uaye SUOTIeASTS WO}0G FO SaTIOASTY UT], apts yynog “q "O°N MINDS JYs 939 1b 69 3NI7 31140Y¥d O35 NOLL Bt 930 AON 190 43S on¥ nr NAT AWN Yds YBN 834 NUP OO" ¥L (UV JZ9NULSIO ONISSIN BLBO . MYBNHSN38 SHL ST WNLBO WLNDZ1YOH Vsh ST WALBO TIWOLLY3A BA313 NI 3ONBHI — — i ' oe 6- (HW) NOILBAIT3 N 1H B89 3NI7 311308d "919 eansty apis yAZON ‘ke yel)R NO‘ 443 3439 ? ent cor NOILYAIIZ NI 3ONBHD oe6t 930 AON 100 43S On¥ Jar Nar ABN Ydd YUN 833 NUT 00° Le {W JZ9NULSIO ONISSIW BLUO MY MYBNHINIG SHL ST WALWO WWLNOZIYOH sl St WALYO WOTLY3A Ll- s- (W 7 NOILBAR13 C18 (09+01I uotzeqs tatd) Ww €z7E ze Usye SuUOTIeAaTI WOIQOG FO SaTIOYSTY oUWTT "419 ean3sty apts yynog “q apts YON ‘ke “ON MONO’ 3YS 9439 “O"N “483 9439 1b 69 3NI7 31140¥d YO NOILBAIIZ NI 3ONBHI iy 89 antsy sar awe Woy RO SERE NI 3ONBHI OB61 oBst 230 AON 190 43S ONb ON NA AYN Udy YBN a3 Nur 00° Eze {W )3Z9NbLSIO a Oo° Eze nm nh ae (WH )ZONULSIO Fs] 3 z ae Re ' w ' % ONISSIN dJlbO >, ONISSIN ULUO *, N MYBNHINZE ZHL MYBNHOINSE SHL SI WNL8O WWINDZTYOH SI WALYO TWINOZIYOH VSN SL WNLBO WUILYZA os YSW ST WALYO WILLY3A 930 AON 190 d3S ONY Wr NNF ABN Ydb SYN 834 NUP i — + — + Se o S- (Wo 2 NOTLYA3T3 t- C19 (O8+€1 uoTIeqs taTd) W TZ7 37& Usxe} SuUOTJeAITa WOJJOG FO SaTIOJSTY aWT, “gIQ aan3ty apts yynog -q “O°N MONO* Ys 9439 1b 69 3NI) 371404¥d YOS NOILYAS13 NI 3uNBHI 086? 930 AON 190 d3S on nr NNf AUN Ydd SON G34 NUP 00° t2y (W )39NBLSIO | ONISSIN YlbO >, . SI NNL8O WLNOZ1YOH TSW ST WALYO TWOLLY3A @- (WJ NO*LBA313 apts yWION -‘e J WONO* 4y¥45 9439 “ON 1B 89 4NI7 311504¥c YOS NOITLBAI13 NI 3ONKHO 930 AON 1590 43S OfMb IT NAF ABH Ydd YBN 834 NEF So ee eo OO* Lz (No 3Z9NBLSTO ONISSIN YleO *, MYBNHINIG FHL SI WNLbO IWLNOZIYOH TSH ST WALWO WWOLTLYSA 6- e- (Wo) NOTLBA373 C20 (O7+71 Uotqzeys JaTd) ui ¢€y Je usyeq suoTJeAVTS Woj}Oq FO satTioysty out], apts yynog *q “I°N MONO 44 IN3D Jb 59 3NID 31140¥d YOJ_NOLIHAS13_NI_3DNBHD OBST 930 AON 190 d3S On WAr Nar AWN Ydd YBN 835 NUP Si IT cS) ' lie }é o | 3 O° ger t |e (WH )3ONBLSIG | ' an ID 2 ONISSIN BlbO *. N MYBWHINSG FHL SI WNLbO WWLNOZIYOH TSH SI WALYO WWOILLYSA = €- (WH) NOILBAZT3 "619 aansty apts yWION “ke ah N MONG‘ 3¥3 IN39 F11s0Nd YO NOTiBAIIZ NI ZONBHO 930 AON Lvo d3g ond nr NAP ABW Ydd YBN g3j Nur OO° eer (WH )3ONULSIG ONISSIN B1LbO ay WYBNHINSS BHL ST WALYO WWLNOZIYOH sh SI WNLHO WOIILY3A t a Q y- {WH ) NOTLBAZT3 C21 (09+¥1T wotqeqs tatd) W Cy Je Usye} suUOTJeASTa WOIIOG FO SaTIOASTY JWTL “Q7Z) san3Ty apts y4ynog -q “I°N MONO* 4Y4 3439 16 69 3NID 311404d YO4_NDLLHA313_NI_39NBHIV 230 AON 190 43S 9nd FSS SS SS OO*S+r {NW )JONBLSIO ONISSIN UlbO MYBNHINSS FHL ST WO1WO WWLNOZIYOH TSH ST WALYO IWOILYIA ogst Tar Nar AUN Ydd YBN 634 Nor ot- (WH NOILBAR13 2PTs YAION -e “I°N MONG* 3y¥4d 9N39 V a11508d YOS NOTLBUAIIZ NI JONWHI OB6T lb 89 4NI 930 AON 190 d3S Od INF ANF ABN Ydd YBN 834 NUP OO°S+4 (NW )3DNKLSIG ONISSIN BtbO |. MYBNHON3S SHL SIT NALYO TWLNOZ!YOH TSW SI WALBO WIILY3A as (WH J NOILYAI13 C22 (uotze50T AoTAeg pua Jatd) W 6/G 3e Uayeq SUOTJeASTS WO}}OG FO SaTIOYSTY suUT] apts yqnog -*q at MONO’ 444 439 1b 69 3NI7 311450Yd YOS NOILBASIS NI 3ONBHI 930 AON 190 d3S Ob Nr NAP AUN Ydd YUN 834 NUP 00°6LS {NW J39NeLs10 ONISSIN UlbO ‘ MYBHHINIS FHL SI WALBO WLNOZ1YOH TSH ST WALUG WWOIILYSA (WH) NOILBART3 "17O ean3stTy apts yWION ‘e “ITN YONI! Jus Y39 al d 1H 89 3NI7 311450Y%d YOI NOTLBAS1Z NI 3SONBHD og61 . £30 AON 190 3S on’ “InP NAP AWN Ydy YUN 834 NUP 3 O0°6LS .. | (WH )ZONBLSIG ONISSIN b1UO *. . MYBNHSN3G BHL SI WNLUO TWLNOZIYOH TSH SI WALBO WOTLY3A S 6- (HW 7 NOILBAR13 C23 (07+61 UoTjeqs JaTd) W [6S 3 UayeQ SUOTJeAVTA WOR}OG FO SaTIOASTY awTy “779 asan3ty apts yqynog -q “S°N MONG’ dus 9439 18 69 3NI7 311304¥d YO4 NOILBASIZ NI SONBHI 930 AON 190 d3S Ond INT NAr AWN dd YBN 833 NOP 00° t6s (W )ZONULSIO 00 (Wo 35N (WH) NOILBA3R13 ONISSIN Bilbo *, MYBNHINIS FHL SI NALBO WLNOZTYOH TSH ST WALYO WOITLY3SA as ‘s' apts yqION ‘eke “O°N MONS aud 9N9D 1B 89 3NIT 311S0¥d YOs NOiLUASIa NI 3ONBHO oa61 930 AON 190 d3S ON’ TNF NAC AUN Ydd YUN 834 NEC “16S HLSIa ONISSIN BLlbO . MYBNHINSA 3SHL SY WAl¥O TWLNOZIYOH ST WALYO WOITLYIA (4) NOI18A313 C24 p \\ ij ; Ns i