OSs see | Gas: Excg. i@s. Cty, feck. Moy. CRC-Y6-13 Jul [4% TECHNICAL REPORT CERC-90-13 US Army Corps ANNUAL DATA SUMMARY FOR 1988 offEnginee'S CERC FIELD RESEARCH FACILITY Volume | MAIN TEXT AND APPENDIXES A AND B by Michael W. Leffler, Kent K. Hathaway Brian L. Scarborough, Clifford F. Baron Herman C. Miller -Coastal Engineering Research Center DEPARTMENT OF THE ARMY Waterways Experiment Station, Corps of Engineers 3909 Halls Ferry Road, Vicksburg, Mississippi 39180-6199 July 1990 Final Report Approved For Public Release; Distribution Unlimited Prepared for DEPARTMENT OF THE ARMY US Army Corps of Engineers Washington, DC 20314-1000 Under FRF Analysis Work Unit 32525 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. _.___Unclassified __ x SECURITY CLASSIFICATION OF THIS PAGE =< REPORT DOCUMENTATION PAGE arery are la. REPORT SECURITY CLASSIFICATION 1b. RESTRICTIVE MARKINGS Unclassified 2a. SECURITY CLASSIFICATION AUTHORITY 3. DISTRIBUTION / AVAILABILITY OF REPORT Approved for public release; distribution 2b. DECLASSIFICATION / DOWNGRADING SCHEDULE unlimited. 4. PERFORMING ORGANIZATION REPORT NUMBER(S) 5. MONITORING ORGANIZATION REPORT NUMBER(S) Technical Report CERC-90-13 6a. NAME OF PERFORMING ORGANIZATION 6b. OFFICE SYMBOL 7a. NAME OF MONITORING ORGANIZATION USAEWES, Coastal Engineering (if applicable) Research Center 6c. ADDRESS (City, State, and ZIP Code) 7b. ADDRESS (City, State, and ZIP Code) 3909 Halls Ferry Road Vicksburg, MS 39180-6199 8a. NAME OF FUNDING/ SPONSORING 8b. OFFICE SYMBOL 9. PROCUREMENT INSTRUMENT IDENTIFICATION NUMBER ORGANIZATION (If applicable) US Army Corps of Engineers 8c. ADDRESS (City, State, and ZIP Code) 10. SOURCE OF FUNDING NUMBERS PROGRAM PROJECT TASK WORK UNIT Washington, DC 20314-1000 ELEMENT NO. | NO. NO. JACCESSION NO. 11. TITLE (Include Security Classification) Annual Data Summary for 1988, CERC Field Research Facility; Volume I: Main Text and Appendixes A and B; Volume II: Appendixes C Through E 12. PERSONAL AUTHOR(S) See reverse. 13a. TYPE OF REPORT Final 13b. TIME COVERED 14. DATE OF REPORT (Year, Month, Day) }15. PAGE COUNT 205 report in 2 volumes | FROM_______ TO___ July 1990 (In two volumes) 16. SUPPLEMENTARY NOTATION See reverse. COSATI CODES 18. SUBJECT TERMS (Continue on reverse if necessary and identify by block number) GROUP SUB-GROUP See reverse. 19. ABSTRACT (Continue on reverse if necessary and identify by block number) This report provides basic data and summaries for the measurements made during 1988 at the US Army Engineer Waterways Experiment Station (WES), Coastal Engineering Research Center's (CERC's) Field Research Facility (FRF) in Duck, NC. The report includes comparisons of the present year's data with cumulative statistics from 1980 to the present. Summarized in this report are meteorological and oceanographic data, monthly bathymetric survey results, samples of quarterly aerial photography, and descriptions of 16 storms that occurred during the year. The year was highlighted by a severe storm in April that destroyed several oceanfront cottages. Waves with 5-m significant height were measured 6 km from shore. (Continued) 20. DISTRIBUTION / AVAILABILITY OF ABSTRACT 21. ABSTRACT SECURITY CLASSIFICATION GI UNCLASSIFIED/UNLIMITED (J SAME AS RPT. C1 otic Users Unclassified 22a. NAME OF RESPONSIBLE INDIVIDUAL 22b. TELEPHONE (include Area Code) | 22c. OFFICE SYMBOL DD Form 1473, JUN 86 Previous editions are obsolete. SECURITY CLASSIFICATION OF THIS PAGE Went UMN 0 0301 0091273 Unclassified SECURITY CLASSIFICATION OF THIS PAGE PERSONAL AUTHOR(S) (Continued). Leffler, Michael W.; Hathaway, Kent K.; Scarborough, Brian L.; Baron, Clifford F.; Miller, Herman C. 16. SUPPLEMENTARY NOTATION (Continued). A limited number of copies of Volume II (Appendixes C through E) were published under separate cover. Copies of Volume I (this report and Appendixes A and B) are available from National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161. 18. SUBJECT TERMS (Continued). Meteorologic research--statistics (LC) Oceanographic research--statistics (LC) Oceanographic research stations--North Carolina--Duck (LC) Water waves--statistics (LC) 19. ABSTRACT (Continued). This report is tenth in a series of annual summaries of data collected at the FRF that began with Miscellaneous Report CERC-82-16, which summarizes data collected during 1977-1979. These reports are available from the WES Technical Report Distribution Section of the Information Technology Laboratory, Vicksburg, MS. SECURITY CLASSIFICATION OF THIS PAGE PREFACE This report is the tenth in a series of annual data summaries authorized by Headquarters, US Army Corps of Engineers (HQUSACE), under Civil Works Research Work Unit 32525, Field Research Facility Analysis, Coastal Flooding Program. Funds were provided through the US Army Engineer Waterways Experi- ment Station (WES), Coastal Engineering Research Center (CERC), under the pro- gram management of Dr. C. Linwood Vincent, CERC. Mr. John H. Lockhart, Jr., was HQUSACE Technical Monitor. The data for the report were collected and analyzed at CERC's Field Research Facility (FRF) in Duck, NC. The report was prepared by Mr. Michael W. Leffler, Computer Programmer Analyst, FRF, under the direct supervision of Mr. William A. Birkemeier, Chief, FRF Group, Engineering Development Division (EDD), and Mr. Thomas W. Richardson, Chief, EDD; and under the general super- vision of Dr. James R. Houston and Mr. Charles C. Calhoun, Jr., Chief and Assistant Chief, CERC, respectively. Mr. Kent K. Hathaway, Oceanographer, FRF, assisted with instrumentation; and Mr. Brian L. Scarborough, Amphibious Vehicle Operator, FRF, assisted with data collection. Messrs. Herman C. Miller. Clittord f, Baron, John B.. Strider, Jr., James E. Martin, and Mark A. McConathy and Mses. Deborah R. Heibel and Wendy L. Smith assisted with data analysis at the FRF. The National Oceanic and Atmospheric Administration/National Ocean Service maintained the tide gage and provided statistics for summarization. Commander and Director of WES during the publication of this report was COL Larry B. Fulton, EN. Dr. Robert W. Whalin was Technical Director. CONTENTS PREFACE . PART PART PART PART PART PART PART PART PART I: INTRODUCTION . Background ait Organization of Report Availability of Data II: METEOROLOGY . Air Temperature Atmospheric Pressure Precipitation . : Wind Speed and Diceetion III: WAVES Measurement Instruments Digital Data Analysis and summarization ; Results IV: CURRENTS Observations Results V: TIDES AND WATER LEVELS Measurement Instrument Results VI: WATER CHARACTERISTICS Temperature Visibility Density . VII: SURVEYS VIII: PHOTOGRAPHY . Aerial Photographs Beach Photographs IX: STORMS REFERENCES 58 74 APPENDIX A: SURVEY DATA . APPENDIX B: WAVE DATA FOR GAGE 630 Datly Hy and 05 7 u Joint Distributions of He and > Cumulative Distributions of Wave Height : Peak Spectral Wave Period Distributions Persistence of Wave Heights Spectra . APPENDIX C™: WAVE DATA FOR GAGE 111 Datlys Hoo, and) 2). al Epi t) Gan Joint Distributions of fe and T Cumulative Distributions of Wave Height . Peak Spectral Wave Period Distributions Persistence of Wave Heights Spectra . APPENDIX D: WAVE DATA FOR GAGE 625 . Datily) “HEo, andy lamers Auliieguli ss ei Joint Distributions of Hee and T, Cumulative Distributions of Wave Height . Peak Spectral Wave Period Distributions Persistence of Wave Heights Spectra . APPENDIX E: WAVE DATA FOR GAGE 645 Datly, Hi, and) to. - é Joint Distributions of He and. T, Cumulative Distributions of Wave Height : Peak Spectral Wave Period Distributions Persistence of Wave Heights Spectra . * A limited number of copies of Appendixes C-E (Volume II) were published under separate cover. Copies are available from National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161. 3 ANNUAL DATA SUMMARY FOR 1988 CERG FIELD RESEARCH FACILITY PART I: INTRODUCTION Background 1. The US Army Engineer Waterways Experiment Station (WES), Coastal Engineering Research Center’s (CERC’s) Field Research Facility (FRF), located on 0.7 km? at Duck, NC (Figure 1), consists of a 561-m-long research pier and accompanying office and field support buildings. The FRF is located near the middle of Currituck Spit along a 100-km unbroken stretch of shoreline extend- ing south of Rudee Inlet, VA, to Oregon Inlet, NC. The FRF 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 complement labora- tory 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-diam steel piles spaced 12.2 m apart along the pier’s 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 the National Geodetic Vertical Datum (NGVD). The pilings are protected against sand abrasion by concrete erosion collars and against corrosion by a cathodic system. 3. An FRF Measurements and Analysis 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, which summarizes data for 1988, continues a series of reports begun in 1977. CHESAPEAKE ; BAY FACILITY A =e 0 10 20 30KM 1 CAPE SE ees HATTERAS Figure 1. FRF location map Organization of Report 5. This report is organized into nine parts and five appendixes. Part I is an introduction; Parts II through VIII discuss the various data col- lected during the year; and Part IX describes the storms that occurred. Appendix A presents the bathymetric surveys, Appendix B summarizes deep-water wave statistics, and Appendixes C through E (published under separate cover as Volume II) contain summary statistics for other gages. 6. In each part of this report, the respective instruments used for monitoring the meteorological or oceanographic conditions are briefly described along with data collection and analysis procedures and data results. The instruments were interfaced with the primary data acquisition system, a Digital Equipment Corporation (Maynard, MA) VAX-11/750 minicomputer located in the FRF laboratory building. More detailed explanations of the design and the operation of the instruments may be found in Miller (1980). Readers’ comments on the format and usefulness of the data presented are encouraged. Availability of Data 7. Table 1 summarizes the available data. In addition to the wave data summaries in the main text, more extensive summaries for each of the wave gages are provided in Appendixes B through E. Table 1 1988 Data Availability Gage Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec TD) 222394051 22304 Te 22 3h Te Qe3 verse 2eSna Li 2 Suey i 2u3NGn5 12 Susy 2° 3G) 2e3 nas 1e2nShanle2Es na Weather Anemometer 632k ke eR ea RK [Rf kk Oe Atmospheric Pres. 616 * * ¥ # KW woke Re] kok fe fe oo [tok io Air Temperature 624 RRR a a a [ka RK [RK Precipitation 604A AKA KARR RA al KR a a fk ek Waves Offshore Waverider 630 * * #¥ kw RK RK fo fe [eK fa fk fw ww] [foe fee / Pressure Gage VL ek a [a [ke ek Pier End 625 * kaa a af RK [ok ee WK Pier Nearshore 645 KR KR fe | a [kK [we [ok Currents Pier End a ed Pier Nearshore a a ee ee ad Beach ee a a a a a eed Pier End Tide Gage Se ee ee ee a ay Water Characteristics Temperature ee Visibility eo Density ee as Bathymetric Surveys * ied ae v LJ * Ce ok Photography Beach a ee eo Aerial * * * * * Notes: ™* Full week of data obtained. / Less than 7 days of data obtained. - No data obtained. 8. The annual data summary herein summarizes daily observations by month and year to provide basic data for analysis by users. Daily measure- ments and observations have already been reported in a series of monthly Preliminary Data Summaries (Field Research Facility 1988). If individual data for the present year are needed, the user can obtain detailed information (as well as the monthly and previous annual reports) from the following address: USAE Waterways Experiment Station Coastal Engineering Research Center Field Research Facility SR Box 271 Kitty Hawk, NC 27949-9440 Although the data collected at the FRF are designed primarily to support ongoing CERC research, use of the data by others is encouraged. The WES/CERC Coastal Engineering Information and Analysis Center (CEIAC) is responsible for storing and disseminating most of the data collected at the FRF. All data requests should be in writing and addressed to: Commander and Director US Army Engineer Waterways Experiment Station ATTN: Coastal Engineering Information Analysis Center 3909 Halls Ferry Road Vicksburg, MS 39180-6199 Tidal data other than the summaries in this report can be obtained directly from the following address: National Oceanic and Atmospheric Administration National Ocean Service ATTN: Tide Analysis Branch Rockville, MD 20852 A complete explanation of the exact data desired for specific dates and times will expedite filling any request; an explanation of how the data will be used will help CEIAC or the National Oceanic and Atmospheric Administration (NOAA) /National Ocean Service (NOS) determine if other relevant data are available. For information regarding the availability of data for all years, contact CEIAC at (601) 634-2012. Costs for collecting, copying, and mailing will be borne by the requester. PART II: METEOROLOGY 9. This section summarizes the meteorological measurements made during the current year and in combination with all previous years. Meteorological measurements during storms are given in Part IX. 10. Mean air temperature, atmospheric pressure, and wind speed and direction were computed for each data file which consisted of data sampled two times per second for 34 min every 6 hr beginning at or about 0100, 0700, 1300, and 1900 eastern standard time (EST); these hours correspond to the time that the National Weather Service (NWS) creates daily synoptic weather maps. Dur- ing storms, data recordings were made more frequently. The data are summar- ized in Table 2. Table 2 Meteorological Statistics Mean Mean Wind Resultants Air Temperature Atmospheric Pres. Precipitation, mm 1988 1980-1988 deg C mb 1988 1978-1988 Speed Direction Speed Direction Month 1988 1983-1988 1988 1983-1988 Total Mean Maxima Minima m/sec deg m/sec deg Jan 3.9 5.0 1024.2 1017.8 124 100 180 44 2.6 349 2.6 339 Feb 6.1 6.0 1018.8 1017.3 86 72 86 20 2 313 1.8 350 Mar 9.9 cee 1019.1 1016.2 Y/ 79 168 35 0.2 27 1.4 358 Apr 13.6 13/55 1010.8 1013.2 100 95 182 0 1.4 354 0.4 319 May 17.9 18.8 1014.8 1016.2 49 64 239 20 1.5. 64 0.4 173 Jun 22.2 23.2 1014.7 1015.5 118 80 130 27 0.5 246 1.0 199 Jul 25.8 26.0 1017.8 1016.5 60 81 200 19 3.0 208 aley/ 215 Aug 25.4 26.0 1015.2 1016.5 121 105 221 30 2.0 176 0.5 98 Sep 2S 22.2 1016.9 1018.0 35 72 160 5 30 25 9) 36 Oct alisy al 17.4 LOL} 1019.8 69 64 143 17 23) 352 2.5 27 Nov 13.9 13/53 1016.1 1018.6 120 93 145 26 0.6 331 ale) 357 Dec 6.4 8.2 1020.0 1019.8 16 62 131 4 2.2 301 2.1 335 Average 15.1 pha / 1017.2 1017.2 78 80 0.7 335 0.9 357 Total 935) 967 Air Temperature ll. The FRF enjoys a typical marine climate which moderates the temper- ature extremes of both summer and winter. Measurement instruments 12. A Yellow Springs Instrument Company, Inc. (YSI) (Yellow Springs, OH) electronic temperature probe with analog output interfaced to the FRF’s computer was operated beside the NWS'’s meteorological instrument shelter located 43 m behind the dune (Figure 2). To ensure proper temperature read- ings, the probe was installed 3 m above ground inside a "coolie hat" to shade it from direct sun yet provide proper ventilation. Results 13. Daily and average air temperature values are tabulated in Table 2 and shown in Figure 3. Atmospheric Pressure Measurement instruments 14. Electronic atmospheric pressure sensor. Atmospheric pressure was measured with a YSI electronic sensor with analog output located in the laboratory building at 9 m above NGVD. Data were recorded on the FRF com- puter. Data from this gage were compared with those from an NWS aneroid barometer to ensure proper operation. 15. Microbarograph. A Weathertronics, Incorporated (Sacramento, CA) recording aneroid sensor (microbarograph) located in the laboratory building also was used to continuously record atmospheric pressure variation. 16. The microbarograph was compared daily with the NWS aneroid barometer, and adjustments were made as necessary. Maintenance of the microbarograph consisted of inking the pen, changing the chart paper, and winding the clock every 7 days. During the summer, a meteorologist from the NWS checked and verified the operation of the barometer. 17. The microbarograph was read and inspected daily using the following procedure: a. The pen was zeroed (where applicable). b. The chart time was checked and corrected, if necessary. c. Daily reading was marked on the chart for reference. d. The starting and ending chart times were recorded, as necessary. e. New charts were installed when needed. taken _12 August 1988 & Hil 1:12,000 Baylor Gagef Bay lor No. 645 ME us co” a) iW 7] My HO ia WMT Figure 2. FRF gage locations 10 Year Mean,°C eel —x 1988 yal ons 5 @----© 1983-88 1537, W oa N o i) (2) Ww oO ren nnn ne i . 2 : 10 Air Temperature, °C a [mca hel ae LS Gear T Li T Te Ti 1 JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Month Figure 3. Daily air temperature values with monthly means Results 18. Daily and average atmospheric pressure values are presented in Figure 4, and summary statistics are presented in Table 2. Precipitation 19. Precipitation is generally well distributed throughout the year. Precipitation from midlatitude cyclones (northeasters) predominates in the winter, whereas local convection (thunderstorms) accounts for most of the summer rainfall. Measurement instruments 20. Electronic rain gage. A Belfort Instrument Company (Baltimore, MD) 30-cm weighing rain gage, located near the instrument shelter 47 m behind the dune, measured daily precipitation. According to the manufacturer, the 11 1040 Year Mean, mb *— 1988 1017.2 sis e----0 1983-88 1017.2 10354: £ ; 103042 “: : a Sree ee E é 1025 =) . . 10204-"-+ 2 O 4015 no, 2 4010 (os on E 1005 < 1000 995 A 0g aT a Sa Ina alee JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Month Figure 4. Daily barometric pressure values with monthly means instrument’s accuracy was 0.5 percent for precipitation amounts less than 15 cm and 1.0 percent for amounts greater than 15 cm. 21. The rain gage was inspected daily, and the analog chart recorder was maintained by procedures similar to those for the microbarograph. 22. Plastic rain gage. An Edwards Manufacturing Company (Alberta Lea, MN) True Check 15-cm-capacity clear plastic rain gage with a 0.025-cm resolu- tion was used to monitor the performance of the weighing rain gage. This gage, located near the weighing gage, was compared daily; and very few dis- crepancies were identified during the year. Results 23. Daily and monthly average precipitation values are shown in Figure 5. Statistics of total precipitation for each month during this year and average totals for all years combined are presented in Table 2. itz 22575 Year Total,mm *—~* 1988 935 @----© 1980-88 967 Precipitation, mm ” ~ = JAN FEB M 0 +. {+ —S AR APR MAY JUN JUL AUG SEP OCT NOV DEC Month Figure 5. Daily precipitation values with monthly totals Wind Speed and Direction 24. Winds at the FRF are dominated by tropical maritime air masses which create low to moderate, warm southern breezes; arctic and polar air masses which produce cold winds from northerly directions; and smaller scale cyclonic, low pressure systems, which originate either in the tropics (and move north along the coast) or on land (and move eastward offshore). The dominant wind direction changes with season, being generally from northern directions in the fall and winter and from southern directions in the spring and summer. It is common for fall and winter storms (northeasters) to produce winds with average speeds in excess of 15 m/sec. Measurement instrument 25. Winds were measured on top of the laboratory building at an ele- vation of 19.1 m (Figure 2) using a Weather Measure Corporation (Sacramento, CA) Skyvane Model W102P anemometer. Wind speed and direction data were 13 collected on the FRF computer as well as on a strip-chart recorder. The anemometer manufacturer specifies an accuracy of +0.45 m/sec below 13 m/sec and 3 percent at speeds above 13 m/sec, with a threshold of 0.9 m/sec. Wind direction accuracy is +2 deg with a resolution of less than 1 deg. The ane- mometer is calibrated annually at the National Bureau of Standards in Gaithersburg, MD, and is within the manufacturer's specifications. Results 26. Annual and monthly joint probability distributions of wind speed versus direction were computed. Winds speeds were resolved into 3-m/sec intervals, whereas the directions were at 22.5-deg intervals (i.e. 16-point compass direction specifications). These distributions are presented as wind "roses," such that the length of the petal represents the frequency of occur- rence of wind blowing from the specified direction, and the width of the petal is indicative of the speed. Resultant directions and speeds were also deter- mined by vector averaging the data (see Table 2). Wind statistics are pre- sented in Figures 6, 7, and 8. 14 N 337.50.0 995 315.0 45.0 67.5 292.5 i? a* 6 cae 90.0E 270.0 = ag nae Re 225.0 135.0 202.5 180.0 7"? S 1988 Speed 0.7 m/s Direction 335 deg N 337.50.0 995 315.0 45.0 67.5 292.5 q 1p a 2 ns 90.0E 270.0 = oat wy FG) Wad 112.5 Beis 135.0 202.5 180.0”? S 1980-1988 Speed 0.9 m/s Direction 357 deg 0 105) 20> SS 07he40 Frequency, % Figure 6. Annual wind roses 15 N N 337.50.0 995 337.50.0 995 315.0 is 45.0 315.0 45.0 292.5 Nw oe 292.5 RY 7 A oh 247.5 Cp i ~ 112.5 247.5 aT VY oes 135.0 SRG 135.0 202.5 180.0 97° 202.5 180.0 ©7"> S S JANUARY FEBURARY Speed 2.6 m/s Speed 1.2 m/s Direction 349 deg Direction 313 deg N N 337.50.0 99, a 337.50.0 995 315.0 315.0 45.0 292.5 y pe es 292.5 ah lal o gees W EW ~ E 270.0 S oe 270.0 = = eons oo ox 247.5 b, = 112.5 247.5 Sf ° 112.5 202.5 180.0 97° 202.5 180.0 97° S SS MARCH APRIL Speed 0.2 m/s Speed 1.4 m/s Direction 27 deg Direction 354 deg Speed, m/sec I Los a) ee ella A oe ice ——— 0 “10Me20 MISO NAZO Frequency, % Figure 7. Monthly wind roses for 1988 (Sheet 1 of 3) 16 N 33715 O10 Maan 45.0 292.5 xi i7 ee fe Zs pert = 90.0E 2 247.5 Zaks 112.5 225.0 135.0 202.5 180.07" S MAY Speed 1.5 m/s Direction 64 deg N 337.5 0.0 315.0 45.0 67.5 | 2925 8 y x on = 90.0E & ms, | ow 112.5 5.0 135.0 180.0 7-9 S JU Speed 3.0 m/s Direction 208 deg N 337.50.0 995 315.0 45.0 292.5 ot ‘9 ote A D WHoe = 90.0E : oy aU \ 112.5 ae 135.0 202.5 180.0 7° S JUNE Speed 0.5 m/s Direction 246 deg N 337.50.0 995 315.0 AS.0 67.5 92.5 oe rs e W —s 90.0E > 08 \ 112.5 Ll | \ 135.0 202.5 180.0 97° S AUGUST Speed 2.0 m/s Direction 176 deg Speed, m/s Gy es ne) 7 2 fe ate ait AG Len e2Mmeoang 0 10 20 40 Frequency, % Figure 7. (Sheet 2 of 3) N N 337.5 0.0 337.50.0 995 45.0 315.0 f 45.0 292.5 al C4 Pte 292.5 nail oa gre ‘ > zo Wests) oa! i $0.0 Wenn wp ‘ 90.0E _s oa a 247.5 Ci y AN 112.5 247.5 ff l o* 112.5 225.0 225.0 135.0 202.5 180.0 7-9 202.5 180.0 ©/"> S S SEPTEMBER OCTOBER Speed 3.0 m/s Speed 2.35. m/s Direction 25 deg Direction 352 deg N N 337.50.0 995 337.50.0 995 315.0 5.0 315.0 I 45.0 292.5 4a y Zz S79 292.5 ‘\s y ge nN co Sie, @ Ho a SOOT | Wika tan : 90.0E 247.5 vy] 112.5 247. L 225.0 a 135.0 225.0 135.0 927-3 02.5 180.0 Ss wsvetiaee DECEMBER Speed 0.6 m/s Speed 2.2 m/s Direction 331 deg Direction 301 deg Speed, m/sec Se Oi ne) oi Ge SIDI Bs Ut ire 2 SLO — oo 0 105.20, S0' 40 Frequency, % Figure 7. (Sheet 3 of 3) 18 N 337.50.0 995 315.0 45.0 292.5 aM i, Sz Wea = a 90.0E 247. ee l "| rea 112.5 295.0 135.0 202.5 180.0 7"> S JANUARY Speed 2.6 m/s Direction 339 deg N 337.50.0 99. 7 315.0 ia 292.5 a 23 eke Westae 90.0E 247. r¢,, fir 112.5 BESO 135.0 202.5 180.0 "> S MARCH Speed 1.4 m/s Direction 358 deg N 337.50.0 99. a 315.0 Lee 292.5 x Se oh Weare oe . 90.0E 247.5 We / 1 Ned 112.5 225.0 135.0 202.5 180.0 "> S FEBURARY Speed 1.8 m/s Direction 350 deg N 337.50.0 995 315.0 45.0 292.5 a4 ip oi a . W ie 90.0E 270.0 ee em 247. So, ae 112.5 225: es => Rg W 570.0 = OO Wee a a 90.0E e, i Vv 112.5 a7 / i \~ 112.5 225.0 4 135.0 225.0 yey 202.5 180.0 97° 202.5 180.0 97> S S MAY JUNE Speed 0.4 m/s Speed 1.0 m/s Direction 173 deg Direction 199 deg N N 337.50.0 995 337.50.0 995 315.0 45.0 315.0 45.0 67.5 67.5 292.5 2 292.5 4 7 - an 7 <* = Pe Re W 970.0 = oe 0) Colo me oe 21850) S a \V 112.5 112.5 Lv 7, hs 5.0 135.0 225.0 135.0 202.5 180.0 7:> 202.5 180.0 7-9 S S JULY AUGUST Speed 1.7 m/s Speed 0.5 ms Direction 215 deg Direction 98 deg Speed, m/sec N © OO me OO Tf He + Len Qreeag —— Frequency, % Figure 8. (Sheet 2 of 3) 20 N 337.50.0 99. i W N 337.50.0 995 315.0 a 315.0 f 45.0 292.5 Pe. 292.5 a3 vA i se ahhh Ss EW a cl 90.0E 270.0 oe ooo 270.0 = 247. ae pe a 112.5 247.5 ey ij j cad 112.5 295.0 135.0 295.0 135.0 202.5 180.0 7-9 202.5 180.0 7-9 S S SEPTEMBER OCTOBER Speed 1.9 m/s Speed 2.5 m/s Direction 36 deg Direction 27 deg N N 337.5 0.0 22.5 337.5 0.0 22. Pi 315.0 45.0 315.0 292.5 ah 7 4 ee 292.5 AM } 2, She 90.0E W es 90.0E 270.0 ba 270.0 aa i 247.5 yy f i at 112.5 O47. VA 1° ¥ 112.5 225.0 [eehe 225.0 Ree 202.5 180.0 97> 202.5 180.0 97-9 S S NOVEMBER DECEMBER Speed 1.9 m/s Speed 2.1 m/s Direction 357 deg Direction 331 deg Speed, m/sec oantea” tev gede Sp ee ee SS 0 10 20 30 40 Frequency, % Figure 8. 21 (Sheet 3 of 3) PART III: WAVES 27. This section presents summaries of the wave data. A discussion of individual major storms is given in Part IX and contains additional wave data for times when wave heights exceeded 2 m at the seaward end of the FRF pier. Appendixes B through E provide more extensive data summaries for each gage, including height and period distributions, wave direction distributions, persistence tables, and spectra during storms. 28. Wave directions (similar to wind directions) at the FRF are season- ally distributed. Waves approach most frequently from north of the pier in the fall and winter and south of the pier in the summer, with the exception of storm waves which approach twice as frequently from north of the pier. Annually, waves are approximately evenly distributed between north and south (resultant wave direction being almost shore-normal). Measurement Instruments 29. The wave gages included two wave staff gages (Gages 645 and 625), one buoy (Gage 630), and one pressure (Gage 111) as shown in Figure 2 and located as follows: Distance Offshore Water Depth Operational Gage Type/Number from Baseline m Period Continuous wire (645) 238 m 3.5 11/84-12/88 Continuous wire (625) 579 m 8 11/78-12/88 Accelerometer buoy (630) 6 km 18 11/78-12/88 Pressure gage (111) 1 km 9 09/86- 12/88 Staff gages 30. Two Baylor Company (Houston, TX) parallel cable inductance wave gages (Gage 645 at sta 7+80 and Gage 625 at sta 19+00 (Figure 2)) were mounted on the FRF pier. Rugged and reliable, these gages require little maintenance except to keep tension on the cables and to remove any material which may cause an electrical short between them. They were calibrated prior to instal- lation by creating an electrical short between the two cables at known dis- tances along the cable and recording the voltage output. Electronic signal conditioning amplifiers are used to ensure that the output signals from the gages are within a O- to 5-V range. Manufacturer-stated gage accuracy is about 1.0 percent, with a 0.1-percent full-scale resolution; full scale is 14 m for Gage 625 and 8.2 m for Gage 645. These gages are susceptible to 22 lightning damage, but protective measures have been taken to minimize such occurrences. A more complete description of the gages’ operational charac- teristics was given by Grogg (1986). Buo age 31. One Datawell Laboratory for Instrumentation (Haarlem, The Nether- lands) Waverider buoy gage (Gage 630) measures the vertical acceleration pro- duced by the passage of a wave. The acceleration signal is double-integrated to produce a displacement signal which is transmitted by radio to an onshore receiver. The manufacturer stated that wave amplitudes are correct to within 3 percent of their actual value for wave frequencies between 0.065 and 0.500 Hz (corresponding 15- to 2-sec wave periods). The manufacturer also specified that the error gradually increased to 10 percent for wave periods in excess of 20 sec. The results in this report were not corrected for the manufacturer’s specified amplitude errors. However, the buoy was calibrated semiannually to ensure that it was within the manufacturer's specification. Pressure gage 32. One Senso-Metrics, Incorporated (Simi Valley, CA), pressure trans- duction gage (Gage 111) installed near the ocean bottom measures the pressure changes produced by the passage of waves creating an output signal which is linear and proportional to pressure when operated within its design limits. Predeployment and postdeployment precision calibrations are performed at the FRF using a static deadweight tester. The sensor's range is 0 to 25 psi (equivalent to O- to 1/7-m seawater) above atmospheric pressure with a manufacturer-stated accuracy of +0.25 percent. Copper scouring pads are installed at the sensor's diaphragm to reduce biological fouling, and the system is periodically cleaned by divers. Digital Data Analysis and Summarization 33. The data were collected, analyzed, and stored on magnetic tape using the FRF’s VAX computer. Data sets were normally collected every 6 hr. During storms, the collection was at 3-hr intervals. For each gage a data set consisted of 4 contiguous records of 4,096 points recorded at 0.5 Hz (approxi- mately 34-min long), for a total of 2 hr and 16 min. Analysis was performed on individual 34-min records. 34. The analysis program computes the first moment (mean) and the 23 second moment about the mean (variance) and then edits the data by checking for "jumps," "spikes," and points exceeding the voltage limit of the gage. A jump is defined as a data value greater than five standard deviations from the previous data value, whereas a spike is a data value more than five standard deviations from the mean. If less than five consecutive jumps or spikes are found, the program linearly interpolates between acceptable data and replaces the erroneous data values. The editing stops if the program finds more than five consecutive jumps or spikes or more than a total of 100 bad points or the variance of the voltage is below 1 x 10-° squared volts. The statistics and diagnostics from the analysis are saved. 35. Sea surface energy spectra are computed from the edited time series. Spectral estimates are computed from smaller data segments obtained by dividing the 4,096-point record into several 512-point segments. The estimates are then ensemble-averaged to produce a more accurate spectrum. These data segments are overlapped by 50 percent (known as the Welch (1967) method) and have been shown to produce improved statistical properties than from nonoverlapped segments. The mean and linear trends are removed from each segment prior to spectral analysis. To reduce sidelobe leakage in the spec- tral estimates, a data window was applied. The first and last 10 percent of data points was multiplied by a cosine bell (Bingham, Godfrey, and Tukey 1967). Spectra were computed from each segment with a discreet Fast Fourier Transform and then ensemble-averaged. Sea surface spectra from subsurface pressure gages were obtained by applying the linear wave theory transfer function. 36. Unless otherwise stated, wave height in this report refers to the energy-based parameter H, defined as four times the zeroth moment wave height of the estimated sea surface spectrum (i.e., four times the square root of the variance) computed from the spectrum passband. Energy computations from the spectra are limited to a passband between 0.05 and 0.50 Hz for sur- face gages and between 0.05 Hz and a high frequency cutoff for subsurface gages. This high frequency limit is imposed to eliminate aliased energy and noise measurements from biasing the computation of H,, and is defined as the frequency where the linear theory transfer function is less than 0.1 (spectral values are multiplied by 100 or more). Smoother and more statistically significant spectral estimates are obtained by band-averaging contiguous spectral components (three components are averaged per band producing a 24 frequency band width of 0.0117 Hz). 37. Wave period T, is defined as the period associated with the maximum energy band in the spectrum which is computed using a 3-point running average band on the spectrum. The peak period is reported as the reciprocal of the center frequency (i.e., T, = 1/frequency) of the spectral band with the highest energy. A detailed description of the analysis techniques is presented in a report by Andrews (1987).° Results 38. The wave conditions for the year are shown in Figure 9. For all four gages, the distributions of wave height for the current year and all years combined are presented in Figures 10 and 11, respectively. Distribu- tions of wave period are presented in Figure 12. 39. Multiple year comparisons of data for Gage 111 actually incorporate data for 1985 and 1986 from Gage 640, a discontinued Waverider buoy previously located at the approximate depth and distance offshore as Gage 111 and data for 1987 from Gage 141, located 30 m south of Gage 111. 40. Refraction, bottom friction, and wave breaking contribute to the observed differences in height and period. During the most severe storms when the wave heights exceed 3 m at the seaward end of the pier, the surf zone (wave breaking) has been observed to extend past the end of the pier and occasionally 1 km offshore. This occurrence is a major reason for the dif- ferences in the distributions between Gage 630 and the inshore gages. The wave height statistics for the staff gage (Gage 645), located at the landward end of the pier, were considerably lower than those for the other gages. In all but the calmest conditions, this gage is within the breaker zone. Consequently, these statistics represent a lower energy wave climate. * M. E. Andrews. 1987. "Standard Wave Data Analysis Procedures for Coastal Engineering Applications," unpublished report prepared for the US Army Engineer Waterways Experiment Station, Vicksburg, MS. 25 44 Jan Jul 2744 0 44 Feb Aug 24 OE May EIU Os ) ral Mar Sep Seal 5 CS) ce lo ea = 0 D nel Apr Oct © 41 4 May Nov 2 6 Pa NON DURA SANA Noe 4 Jun Dec 2. 0 — == 1,35 7 9 1143 18 17°19 212325 27:29 1 3) 5 7. 9) 111315) 17, 19),21/23)25\ 27,2983 Day of the Month 20 Jan Jul 10 () 20 Feb Aug 10 wt NW 0 © 20 Mar Sep YD 10 UP eee IN Nay uae To 2 20- Apr Oct = 14 Wind Oo Ny oo 1 May ' Nov St N oo a c 3 : i ! uw a o oOo 13 5 7 9-11 13.15 17 19 2123252729 1 3 5 7 9 11 13\15\ 17 19) 2123 25.27 29131 Day of the Month Figure 9. Time-histories of wave height and period for Gage 630 26 Height, m Height, m ui bh i) SFT ec ir Sr a ee Earareerr) Ww = 7 ul i nN Ww PS a Er) = 10° 10 Percent Greater Than Indicated Figure 10. 1988 annual wave height distributions Percent Greater Than Indicated Figure 11. Annual distribution of wave heights for 1980 through 1988 27 40 Gage 630 1988 Gage 630 1980—88 20 VAP Viv, 7 V7 Z Be __o Abedin __ oe e oo 5 Gage 111 1988 Gage 111 1985—88 5 20 7 © 7 Ain 7 : Ar ae _ealfablbao_|_.otbolben E ‘< Gage 625 1988 Gage 625 1980—88 & 20 = VA : AV | --o8e0000.2_|_.abalaan Gage 645 Gage 645 1980—88 20 Figure 12. Annual wave period distributions for all gages 41. Summary wave statistics for the current year and all years combined are presented for Gage 630 in Table 3. 28 Table 3 Wave Statistics for Gage 630 1988 1980-1988 Height Period Height Period Std. Std. Std. Std. Mean Dev. Extreme Mean Dev. Number Mean Dev. Extreme Mean Dev. Number Month m m m Date sec sec Obs. m m m Date sec sec Obs. Jan ee 0.6 a) 8 8.5 Soul 124 alse 0.7 4.5 1983 8.0 2.8 950 Feb ital 0.6 2rd: 28 7.8 2.6 116 a2) 0.7 Byaal 1987 8.5 2.6 905 Mar 1.0 0.4 pane 11 7.8 2.2 121 ales 0.7 4.7 1983 8.6 2h) 998 Apr aba} 0.9 Bar 13 8.9 S51 116 al eet 0.7 O73 1988 8.7 2.8 975 May 1.0 0.5 252: 7 8.6 1.6 alatst 0.9 OFS) 323 1986 8.1 2:3) 983 Jun 0.8 0.5 2.4 4 8.0 2.0 101 0.8 0.4 2.4 1988 Uc 2.2 927 Jul 0.7 0.2 Lil 1 7.9 nays 121 0.7 0.3 Dyed: 1985 8.1 Aa) 948 Aug 0.8 0.3 1.6 31 7.4 Paeiah 119 0.8 0.5 B16) 1981 7.9 2.4 949 Sep ako OS) Qin: 8 7.8 20, 111 1.0 0.6 6.1 1985 8.5 2.6 960 Oct 1.0 0.5 2.6 8 9.3 PART) 108 ate) a7/ 4.3 1982 8.7 2.8 1039 Nov algal 0.5 2.4 24 6.8 Qi 94 12) Ol, 4.1 1981 7.9 2.8 861 Dec 1.0 0.5 2.6 4 7.6 e\Gr4 118 beget 0.7 5.6 1980 8.3 3.0 887 Annual 1.0 0.6 Sa? Apr 8.0 2.6 1360 1.0 0.6 6.1 Sep 1985 8.3 Any salable}: 42. Annual joint distributions of wave height versus wave period for Gage 630 are presented for 1988 in Table 4, and for all years combined in Table 5. Similar distributions for the other gages are included in Appendixes B-E. 43. Annual distributions of wave directions (relative to True North) based on daily observations of direction at the seaward end of the pier and height from Gage 625 (or Gage 111 when data for Gage 625 were unavailable) are shown in Figure 13. Monthly wave "roses" for 1988 and all years combined are presented in Figures 14 and 15, respectively. 29 Height (m) 00 - 0.49 50G—810).:99 00 - 1.49 50 = 1.99 00 - 2.49 SOF=—92599 00 - 3.49 50/="3.99 00 - 4.49 50 - 4.99 00 - Greater Ur rwWWNNRRPOO Annual Joint Distribution of H,, versus 0=553)0= 259) 329 88 22 66 147 154 169 Percent Occurrence(X100) of Height and Period O=9e5310= 4.9 529 22 103 301 662 184 515 22 265 29 7 S298 158i 1331 Table 4 10.0- 12.0- 14.0- 1213 213 T, for Gage 630 16.0- Annual 1988 Period(sec) 7.0- 8.0- 9.0- 7.9 8.9 9.9 96 301 301 610 1051 904 221 206 199 74 110 74 44 S1 15 7 5 15 22 7 7 15 7 : 7 1074 1748 1522 Table 5 Annual Joint Distribution of H, versus Height (m) 00 - 0.49 50 - 0.99 00 - 1.49 50) —915.199, 00 - 2.49 50) 7725.99 00 - 3.49 D0 eS..99) 00 - 4.49 50 - 4.99 .00 - Greater UF eFWWHNHPRPPRP OO Total Period(sec) O=5 03)/40= Zo 5 28 18 39 128 10 67 156 O= ,0= 4.9 PAC) 28 62 254 499 134 402 13 156 2 26 al 431 1146 Annual 1980-1988 Percent Occurrence(X100) of Height and Period 9).10- T, for Gage 630 (All Years) 10..0— 12.0—"14..0= 16 .0- AO Mar Sri9 200 76 812 151 360 39 139 35 70 29 38 abil 17 4 10 4 7 1 3 F : 2 1656 352 15.9 _Longer 134 4 213 15 132 4 77 4 41 2 23 9 4 2 1 0 636 29 1988 Height 0.7 m Direction 59 deg 1980-1988 Height 0.8 m Direction 66 deg Height, m oO. FO i) Oo N be) bse wo 0 20 40 60 80 100 Frequency, % Figure 13. Annual wave roses Sil N 0.0 99.5 0.0 99.5 45.0 45.0 : 9. 67.5 af 67.5 vy = 112.5 V3s) S S JANUARY FEBRUARY Height 0.9 m Height 0.8 m Direction 59 deg Direction 57 deg N N 22.5 0.0 99.5 45.0 45.0 iP 67.5 7 oy 67.5 SES -_ = 2 any 11255 % VAS 15725 157.5 S S MARCH APRIL Height 0.7 m Height 0.9 m Direction 54 deg Direction 54 deg Height, m Oo. (O. Hom ro Pe oninein Opel) 07 207 40) 60" 80) 100 Frequency, % Figure 14. Monthly wave roses for 1988 (Sheet 1 of 3) 32 13 —__ E ~ 112.5 S MAY Height 0.7 m Direction 75 deg 45.0 67.5 eee 90.0E ~ 112.5 135.0 S JUNE Height 0.6 m Direction 54 deg AUGUST Height 0.5 m Direction 91 deg Height, m Creer Re ES eto) eesti iat 40 60 80 100 Frequency, % N 22:5 f . CN 135.0 S JULY Height 0.3 m Direction 85 deg ° [o) (o) — (0) 20 Figure 14. (Sheet 2 of 3) 33 N D259 45.0 ly 67.5 —— 90.0E gS Ass S SEPTEMBER Height 0.8 m Direction 50 deg N 0.0 992.5 45.0 3 gy yo 67.5 S NOVEMBER Height 0.8 m Direction 55 deg 45.0 q 67.5 Wicca 90.0E 112.5 S OCTOBER Height 0.8 m Direction 48 deg N 0.0 92.5 45.0 V4 67.5 cS ox | a 90.0E 2 S 112.5 135.0 S DECEMBER Height 0.7 m Direction 54 deg Height, m 1 8O) BO GO t w © oO ro) = N Mm 0 20 40 60 80 100 Frequency, % Figure 14. (Sheet 3 of 3) 34 N 0.0 99.5 45.0 a 7 vA 67.5 oy ¢ 112.5 135.0 S JANUARY Height 0.9 m Direction 57 deg -7f, el] oe 112.5 135.0 15725 S MARCH Height 0.9 m Direction 66 deg 2 ° 0 Figure 15. 45.0 vA ie ay Ss 112.5 155.0 157.5 S FEBRUARY Height 1.0 m Direction 63 deg APRIL Height 0.8 m Direction 67 deg Height, m ° S > S S SG De) v To) 20 40 608.0) 9100 Frequency, % Monthly wave roses for 1980 through 1988 (Sheet 1 of 3) 35 MAY Height 0.7 m Direction 74 deg JULY Height 0.4 m Direction 80 deg JUNE Height 0.5 m Direction 75 deg AUGUST Height 0.6 m Direction 75 deg Height, m Oe COLO Sy Oni = a > Hg: CN GUN acim L OF 5205, 540 "607, 480) 10.0 Frequency, % Figure’ 15) )(Sheet 2) of 3) 36 N 22.5 0.0 92.5 45.0 45.0 67.5 67.5 Bee ae so Sey oy 112.5 . 112.5 135.0 135.0 S S SEPTEMBER OCTOBER Height 0.8 m Height 1.0 m Direction 67 deg Direction 66 deg N 0.0 99.5 0.0 99.5 45.0 45.0 s » 2 67.5 a ip. 67.5 eH 90.0E Si 1 90r0\b ay oy bi 112.5 112.5 135.0 135.0 S S NOVEMBER DECEMBER Height 0.9 m Height 0.8 m Direction 61 deg Direction 59 deg Height, m S) ro) ° o = Ss) o ame oy Nn + Tey 0 20 40 60 80 100 Frequency, % Figure 15 (Sheet 3 of 3) 37 PART IV: CURRENTS 44. Surface current speed and direction at the FRF are influenced by winds, waves, and, indirectly, by the bottom topography. The extent of the respective influence varies daily. However, winds tend to dominate the cur- rents at the seaward end of the pier, whereas waves dominate within the surf zone. Observations 45. Near 0700 EST, daily observations of surface current speed and direction were made at (a) the seaward end of the pier, (b) the midsurf position on the pier, and (c) 10 to 15 m from the beach 500 m updrift of the pier. Surface currents were determined by observing the movement of dye on the water surface. Results 46. Annual mean and mean currents for 1980 through 1988 are presented in Table 6 and in Figure 16. Figure 16 shows the daily and average annual measurements at the beach, pier midsurf, and pier end locations. Since the relative influences of the winds and waves vary with position from shore, the current speeds and, to some extent, direction vary at the beach, midsurf, and pier end locations. Magnitudes generally are largest at the midsurf location and lowest at the end of the pier. 38 Table 6 Mean Longshore Surface Currents* Pier End, cm/sec Pier Midsurf, cm/sec Beach, cm/sec 1980- 1980- 1980- Month 1988 1988 1988 1988 1988 1988 Jan 7 16 10 20 4 13 Feb 15 18 3 11 15 12 Mar 14 16 3 14 33 14 Apr 8 11 =19) 1 6 8 May 21 alg 14 -4 =3 -1 Jun 4 5 -15 -8 -10 =n) Jul 10 3 12 -16 ie} -9 Aug =10 8 bl -12 -28 -5 Sep 4 7 -26 -6 —30 =] Oct 18 9 al 0 5 2 Nov als} 14 16 8 7 ats Dec Al 14 -13 14 7 8 Annual 9 alat =£) 2 1 4 * + = southward; - = northward. 39 Pier End r Mean, cm/s 8 9 o-88 11 North South are re Current Speed, cm/s Mean, cm/s ar —« 1988 =-3 1980 = = ef @=-=--0 -88 2 5 Sh os: z ies . ars . . Ss fs . a as ir BST ex a eioiciue . . & o * * - ¢ o eM + . > Me © * ie : . + - VM, . + ere ° . + . sete y® + tr ee, + ° a iS ° ney Pet kD * pad Lohse. OS a + ra aS . S + + . . . = = - 7 a (3S * —BR> CH = sO) == 7 * = eA Sr Se =€pe e)- -. ere * > + * ©) 5 +* * + . * ey * + ay 4 * . aul ce a fet + MO. <> ot et + ° . +. + Ble Gan ee ee . 5 * 5 oe R “ . = . . Pars fs . . SS . : . + * os . . n . * . . 7 + ° es _ oe + * 3 Beach (500 m Updrift) \.,, Mean, cm/s —« 1988 1 = = — = @=---01980-88 4 5 ‘ + 3 me > ¥ + + ° ee *, * + . * bd . we . 2 ° + a e -¢ cud oF * oat + - + * ° O * + i or ** ue ¢ ‘+ -, V . + + ¢ 2 be . . ene, + ct + + + Cy + oF ° * + o% 5 + . a of « oe a + + = t r= + +, o te - = — = om oof = =n —S——=—=—=-- = SO . . . Py * -7O- . * *, = A, + ¢ mt +¢ 0 * fs * * * CLO ON +e . So + * * ©. 2 oe * © ee e + + M4 * + > > . + A+ vi * one . . . + = = Gage Inoperative = = = = Feb 47 7 7 -33 80 85 28 -69 14 Mar 42 2 3 -37 79 80 19 -58 20 Apr 58 19 19 =21 79 129 13 -62 18 May 51 10 11 -30 81 88 6 =55 14 Jun 50 10 10 -29 79 112 3 a) 6 Jul 42 1 2 -39 81 74 1 =55 30 Aug 46 5 -36 82 77 31 -60 29 Sep 46 6 UH -34 80 89 26 -60 23 Oct 46 8 8 3s 77 83 25) -63 26 Nov 42 3 4 -36 78 93 24 -62 20 Dec 37 = 2) = -41 78 73 ak) -72 rast 1988 46 6 7 -33 79 129 Apr -72 Dec Prior Years 1987 55 15 16 -24 79 113 Jan -63 Nov 1986 60 13 13 =—35 95 123 Dec -108 Jan 1985 59 10 pl =37 96 136 Dec -93 Apr 1984 64 16 16 -32 97 147 Oct -77 Jul 1983 68 19 19 -30 98 143 Jan 73) Mar 1982 58 8 9 -42 99 127 Oct -108 Feb 1981 59 8 9 -42 101 149 Nov —110 Apr 1980 59 8 8 -43 102 118 Mar 119) Mar 1979 60 9 9 -43 103 i272 Feb -95 Sep 1979- 1988 59 tz 12 -36 95 147 Nov 1981 -119 Mar 1980 * Measurements are in centimeters. 43 Water Level, m Water Level, cm » MSL MLW EL ti Vimsinn T a T T ae ro T =) 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 Year Figure 17. Monthly tide and water level statistics relative to NGVD 1988 0.01 0.10 1.00 10.00 25.00 50.00 75.00 90.00 99.00 99.90 99.99 Percent Greater Than Figure 18. Distributions of hourly tide heights and high- and low-water levels 44 1979-88 PART VI: WATER CHARACTERISTICS 52. Monthly averages of daily measurements of surface water tempera- ture, visibility, and density at the seaward end of the FRF pier are given in Table 8. The summaries represent single observations made near 0700 EST and, therefore, may not reflect daily average conditions since such characteristics can change within a 24-hr period. Large temperature variations were common when there were large differences between the air and water temperatures and variations in wind direction. From past experience, persistent onshore winds move warmer surface water toward the shoreline, although offshore winds cause colder bottom water to circulate shoreward resulting in lower temperatures. Table 8 Mean Surface Water Characteristics Temperature Visibility Density deg C m cm 1980- 1980- 1980- Month 1988 1988 1988 1988 1988 1988 Jan 4.6 a0 1.4 12 1.0227 1.0234 Feb 5.6 4.7 PPA nla?) 1.0237 1.0231 Mar oe) 6.6 2.7 15) 1.0243 1.0229 Apr 10.5 10.8 ate} alge) 1.0242 1.0226 May 15.5 15.2 Zee 7ai8) 1.0219 1.0222 Jun 18.9 19.3 225 3.4 1.0220 1.0215 Jul 2153 PALS T/ 3.8 3.8 1.0241 1.0218 Aug 21.9 23% 2) 4.7 3.2 1.0239 1.0209 Sep 21.6 22.6 yaaa 23 1.0230 02721) Oct ae AS T/ 18.9 pbGE) 15 1.0237 1.0218 Nov 14.7 14.7 1.5 1.0 1.0250 1.0230 Dec 9.1 10.1 Ls abel 1.0259 1.0235 Annual ala 14.4 2.4 eco L 1.0237 1.0223 Temperature 53. Daily sea surface water temperatures (Figure 19) were measured with an NOS water sampler and thermometer. Monthly mean water temperatures (Table 8) varied with the air temperatures (see Table 2). 45 Temperature 30.0 Year deg C *—x 1988 14.1 e----© 1980-88 14.4 25.0 O oO oO AS) Sele XK) 6) oa >) ie} 2 RO Q E © - 10.0 oO aut) ie} = 5.0 T maylp mT y aaa JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Month Figure 19. Daily water temperature values with monthly means Visibility 54. Visibility in coastal nearshore waters depends on the amount of salts, soluble organic material, detritus, living organisms, and inorganic particles in the water. These dissolved and suspended materials change the absorption and attenuation characteristics of the water which vary daily and yearly. 55. Visibility was measured with a 0.3-m-diam Secchi disk and, similar to water temperature, variation was related to onshore and offshore winds. Onshore winds moved warm clear surface water toward shore, whereas offshore winds brought up colder bottom water with large concentrations of suspended matter. Figure 20 presents the daily and monthly mean surface visibility values for the year. Large variations were common, and visibility less than 1 m was expected in any month. Monthly means are given in Table 8. 46 Year Mean, m 7.0 *—x 1988 2.4 a o----0 1980-88 2H 6.0 Feitytt 5.0 he Tne 4.0 : ; : Re Water Visibility, m 2.0 =n T T T em UZ Leas Fe JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Month Figure 20. Daily water visibility values with monthly means Density 56. Daily and monthly mean surface density values, plotted in Figure 21, were measured with a hydrometer. Monthly means are also given in Table 8. 47 3 Density, g/cm Year Mean, g/cm* *—* 1988 1.0237 @----© 1980-88 1.0223 Figure 21. Ts AR Um T Ss rt JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Month Daily water density values with monthly means 48 PART VII: SURVEYS 57. Waves and currents interacting with bottom sediments produce changes in the beach and nearshore bathymetry. These changes can occur very rapidly in response to storms or slowly as a result of persistent but less forceful seasonal variations in wave and current conditions. 58. Nearshore bathymetry at the FRF is characterized by regular shore- parallel contours, a moderate slope, and a barred surf zone (usually an outer storm bar in water depths of about 4.5 m and an inner bar in water depths between 1.0 and 2.0 m). This pattern is interrupted in the immediate vicinity of the pier where a permanent trough runs under much of the pier, ending in a scour hole where depths can be up to 3.0 m greater than the adjacent bottom (Figure 22). This trough, which apparently is the result of the interaction of waves and currents with the pilings, varies in shape and depth with chang- ing wave and current conditions. The effect of the pier on shore-parallel contours occurs as far as 300 m away, and the shoreline may be affected up to 350 m from the pier (Miller, Birkemeier, and DeWall 1983). SA. ORG a Figure 22. Permanent trough under the FRF pier, 8 July 1988 49 59. To document the temporal and spatial variability in bathymetry, surveys were conducted approximately monthly of an area extending 600 m north and south of the pier and approximately 950 m offshore. Contour maps result- ing from these surveys along with plots of change in elevation between surveys are given in Appendix A. 60. All surveys utilized the Coastal Research Amphibious Buggy (CRAB), a 10.7-m-tall amphibious tripod, and a Zeiss electronic surveying system described by Birkemeier and Mason (1984). The profile locations are shown in each figure in Appendix A. Survey accuracy was about +3 cm horizontally and vertically. Monthly soundings along both sides of the FRF pier were collected by lowering a weighted measuring tape to the bottom and recording the distance below the pier deck. Soundings were taken midway between the pier pilings to minimize errors caused by scour near the pilings. 61. A history of bottom elevations below Gages 645 and 625 is presented in Figure 23 for their respective pier stations of sta 7+80 (238 m) and sta 19+00 (579 m) along with intermediate locations, 323 and 433 m. 9 —_]| Distance ot (m) =o 238 -3 [Sey < ee _ -5 Qa a -é 323 433 -8 579 -9 JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Month Figure 23. Time-history of bottom elevations at selected locations under the FRF pier 50 PART VIII: PHOTOGRAPHY Aerial Photographs 62. Aerial photography was taken quarterly using a 23-cm aerial mapping camera at a scale of 1:12,000. All coverage was at least 60-percent overlap, with flights flown as closely as possible to low tide between 1000 and 1400 EST with less than 10-percent cloud cover. The flight lines covered are shown in Figure 24. Figure 25 is a sample of the imagery obtained on 12 August 1988; the available aerial photographs for the year are: Date Flight Lines Format 6 Jan 2 Color 3 B/W 25 Apr 2 Color 3 B/W 12 Aug Part of 1 B/W 3 B/W 27 Sep 72 Color 9 Oct 3 B/W 2 Color Rest of 1 B/W Beach Photographs 63. Daily color slides of the beach were taken using a 35-mm camera from the same location on the pier looking north and south (Figure 26). The location from which each picture was taken, as well as the date, time, and a brief description of the picture, was marked on the slides. 51 Not RUOEE INLET SCALE 1-12,000 CAPE HATTERAS . FIELD RESEARCH : | FACILITY Figure 24. Aerial photography flight lines 52 Scale = 1:12,000 Figure 25. Sample aerial photograph, 12 August 1988 53 North View South View ~~ \\ \ ES: ae _ ’ c. 11 March 1988 Figure 26. Beach photos looking north and south from the FRF pier (Sheet 1 of 4) 54 North View South View Wx ae 2 Apriiea9s8s ee 2 Tuner 11988 Figure 26. (Sheet 2 of 4) 2) North View South View b. 12 August 1988 c. 3 September 1988 Figure 26. (Sheet 3 of 4) 56 North View South View a. 13 October 1988 b. 14 November 1988 c. 15 December 1988 Figure 26. (Sheet 4 of 4) oil PART IX: STORMS 64. This section discusses storms (defined here as times when the wave height parameter, H,, equaled or exceeded 2 m at the seaward end of the FRF pier). Sample spectra from Gage 630 are given in Appendix B. Prestorm and/or poststorm bathymetry diagrams are given in Appendix A. Tracking information was provided by NOAA Daily Weather Maps (US Department of Commerce 1988). 3 January 1988 (Figure 27 65. Early on 2 January, strong onshore winds (from north-northeast) generated by a high pressure system centered over Illinois began to affect the FRF. Late on 3 January, the maximum wind speeds exceeded 14 m/sec and the maximum H,, (Gage 625) of 2.19 m( T, = 7.53 sec) was recorded. Precipita- tion totaled 27 mn. Atmospheric Pressure, mb Gage 616 Wind Speed, m/sec Gage 632 ; AU) 0 —— == —— - - -——- 360 Wind Direction, Deg True N Gage 633 270 180 90 1505 Wave Direction, Deg True N Gage 21 25 : 2 — ee peas Aan -30 ae Wave Height, H,,,,™ Gage 625 pull (Eee Se Capes = SS == = Sass = 1 25 Wave Period, Tp sec Gage 625 Up] fee LL PLU UT UL 2 3 4 5 JANUARY 1988 Figure 27. Data for 3 January 1988 storm 58 7-8 January 1988 (Figure 28) 66. Onshore winds, generated by a Canadian high pressure system, were reinforced by the formation of a storm off the NC coast late on 7 January. The storm moved rapidly up the coast and reached Maine by 9 January. winds (from northeast) exceeded 16 m/sec at 0242 EST on 8 January. hours later, the maximum H,, (Gage 625) of 2.85 ( T, = 7.76 sec) and minimum atmospheric pressure of 1011.3 mb were recorded. Precipitation totaled 25 mn. 1040 Atmospheric Pressure, mb Gage 616 Wind Speed, m/sec Gage 632 3 Wave Height, H,,,,m Gage 625 25 Wave Period, Tp sec Gage 625 . Sa Ne ra et o 2 Water Level from NGVD, m Gage1 1 t) Tolls gle ala = rel lg tle | oa oe eo ol lt tT ol Tolar] 6 7 8 9 10 JANUARY 1988 Figure 28. Data for 7-8 January 1988 storm 59 14 January 1988 (Figure 29) 67. A strong high pressure system centered over Illinois produced strong onshore winds (from northeast) at the FRF beginning late on 13 January and continuing through the 14th. The maximum wind speed (exceeding 17 m/sec) and the maximum H,, (Gage 625) of 2.50 ( T, = 7.11 sec) were both recorded at 0700 EST on the 14th. 1040 Atmospheric Pressure, mb Gage 616 Wind Speed, m/sec Gage 632 1505 Wave Direction, Deg True N Gage 21 90 liens z TT 304 rl 35 Wave Height, H,,,,.™ Gage 625 of - 25 Wave Period, T,, sec Gage 625 20 15 Banaue ak NAAN 5 ° 1 2 Water Level from NGVD, m Gage 1 1 0 —— -1 =2 Le LF Te Fo er ST Toten galine oanl meatmlnn!, USL Foal 13 14 15 16 JANUARY 1988 Figure 29. Data for 14 January 1988 storm 60 12 February 1988 (Figure 30) 68. This storm formed over Texas early on 10 February and rapidly intensified as it moved to the north-northeast. By 12 February, it was located over Lake Erie, and two weak secondary lows formed in the Atlantic (one off Cape Hatteras, NC). All three lows merged over New England by 13 February. Maximum onshore winds (from east-northeast) approached 7 m/sec at 0134 EST on 12 February followed several hours later by the maximum H,,, (Gage 625) of 2.25 m (at = 9.14 sec). Minimum atmospheric pressure was 1006.8 mb, and precipitation totaled 25 mm. 1040 Atmospheric Pressure, mb Gage 616 1030 1020 1010 1000 990 1 25 Wind Speed, m/sec Gage 632 20 15 10 5 0 1 360 Wind Direction, Deg True N Gage 633 270 180 90 to) 1 150 Wave Direction, Deg True N Gage 21 90 ne eae = — 30 -30 3 Wave Height, H,,,,m Gage 625 2 ee, ee ne 1 0 1 25 Wave Period, T,, sec Gage 625 20 15 10 Wi ONS 0 7 2 Water Level from NGVD, m Gage 1 1 ° 1 ae ae LAL aI LS RLS PTL OR] al SS) PE oe] a ef LPL Lr a Ta | a] 12 13 4 FEBRUARY 1988 Figure 30. Data for 12 February 1988 storm 61 28 February 1988 (Figure 31 69. Generically known as "Alberta Clipper," this storm roared out of Canada on 26 February and was located off Cape Hatteras, NC, by 28 February. Northerly winds exceeded 16 m/sec early on the 28th with the maximum H,, (Gage 625) of 2.76 m ( T, = 8.00 sec) recorded the same morning. The minimum atmospheric pressure of 1004.4 mb occurred at 1442 EST on 27 February. There was no measurable precipitation with this storm. 1040 Atmospheric Pressure, mb Gage 616 1030 1020 1010 1000 990 1 25 Wind Speed, m/sec Gage 632 20 15 10 5 0 7 360 Wind Direction, Deg True N Gage 633 270 180 90 ° 1 1507 Wave Direction, Deg True N Gage 21 904 304 Ve \/ V / ~304 3 Wave Height, H,,5,™ Gage 625 i a t) 1 25 Wave Period, Tp sec Gage 625 20 15 eo Nee 5 i) 1 2 Water Level from NGVD, m Gage 1 1 0 = 1 —2 Le en a os fr T T T T T T T T T T T T, T T Tool Ling frac Unc La Lie Liar inate | 27 28 29 1 FEBRUARY 1988 Figure 31. Data for 28 February 1988 storm 11 March 1988 (Figure 32) 70. This weak storm formed over Texas early on 9 March and tracked east. Centered over North Carolina on 10 March, the storm quickly moved offshore. Maximum wind speeds (from north-northeast) exceeded 15 m/sec at 2342 EST on 10 March. Wave heights exceeded 2 m only 3 hr with the maximum He (Gage (625) of 22'm (CE, =16.9 sec) occurring)/at 0208) EST) on 11\March. The lowest atmospheric pressure of 999.2 mb was recorded at 0842 EST on 10 March. Precipitation totaled 4 mn. Atmospheric Pressure, mb Gage 616 | Wind Speed, m/sec Gage 632 Be Akg et 360 Wind Direction, Deg True N Gage 633 270 180 20 ee a 0 a) 150 Wave Direction, Deg True N Gage 21 te oe ee 3 Wave Height, H,,4,™ Gage 625 25 Wave Period, Tp sec Gage 625 0 1 2 Water Level from NGVD, m Gage 1 1 ie) Sa ET, a —2 LLL aL] (LL a LO a Far | 10 ab} 12 13 MARCH 1988 Figure 32. Data for 11 March 1988 storm 63 8 April 1988 (Figure 33) 71. This storm formed over the southwestern United States on 30 March and slowly strengthened as it approached the Great Lakes. It dropped to the southeast passing over the Virginia coast early on 8 April and rapidly moved into the Atlantic. On 8 April at 0734 EST, the maximum wind speeds (from north) neared 16 m/sec and the maximum H,, (Gage 625) was 2.8 m (Ge = 9.85 sec). The minimum atmospheric pressure of 994.7 mb occurred early on 7 April. Precipitation amounted to 30 mn. 1040 Atmospheric Pressure, mb Gage 616 1030 1020 1010 1000 es0}—_— 1 25 Wind Speed, m/sec Gage 632 20 15 10 : EN lian SN ee ) 1 360 Wind Direction, Deg True N Gage 633 2704 7-#~— 180 80 0 150 Wove Direction, Deg True N Gage 21 90 ne hot ane GGEmErunaumin i Scr N -30 3 Wave Height, H,,5,m Gage 625 2 1 = OS pet i) =———1) 25 Wave Period, T,, sec Gage 625 20 15 104 A NN 5 0 1 Water Level from NGVD, m Gage 1 LLL LLL USSU US pal eg LIS UL PLL aL Co 9 10 " APRIL 1988 Figure 33. Data for 8 April 1988 storm 64 12-14 April 1988 (Figure 34) 72. After forming over the Gulf of Mexico on 10 April, this storm continued to strengthen as it tracked across the southeast. By 12 April, it was still well inland over Alabama; however, strong onshore winds were being generated at the FRF. As it continued to intensify, the forward movement of the storm slowed, finally moving offshore at Cape Hatteras, NC, on 13 April. This northeaster caused coastal erosion (resulting in the demise of several beach cottages) and flooding at a number of locations along the Outer Banks. Peak winds (from northeast) exceeded 21 m/sec early on 13 April with winds above 15 m/sec continuing for 37 hr. The minimum atmospheric pressure (1001.0 mb) occurred at 0700 EST on 13 April, and the maximum H,, of 4.96 m (T, = 10.24 sec) at Gage 630 occurred several hours later. Total precipita- tion was 47 mm. 1040 Atmospheric Pressure, mb Gage 616 1030 1020 1010 = ee es Sea eT 1000 990 ~ 25 Wind Speed, m/sec Gage 632 20 15 10 5 0 1 360 Wind Direction, Deg True N Gage 633 270 180 90 t) 1 150 Wave Direction, Deg True N Gage 21 90 30 -30 6 Wave Height, H,,,,m Gage 630 5 4 3 2 1 i) 1 25 Wave Period, Tp, sec Gage 630 20 15 10 5 t) 1 2 Water Level from NGVD, m Gage 1 1 C) 1 -2 "1 12 13 14 15 16 APRIL 1988 Figure 34. Data for 12-14 April 1988 storm 65 19 April 1988 (Figure 35) 73. This weak low pressure system began as a cold front over Louisiana on 18 April, rapidly moved to the northeast, and by 20 April moved well offshore. Maximum winds (from north) exceeded 19 m/sec on the afternoon of the 19th while the maximum H,, (Gage 625) of 2.17 m ( T, = 6.92 sec) was attained several hours later. The minimum atmospheric pressure was 1000.8 mb, and precipitation totaled 19 mn. SE a eee mR ee errme pe ea racy 4040 Atmospheric Pressure, mb Gage 616 1030 1020 25 Wind Speed, m/sec Gage 632 20 15 10 5 ° 1 360 Wind Direction, Deg True N Gage 633 270 180 90 0 1 150 Wave Direction, Deg True N Gage 21 Wen a Wave Height, H,,,,™m Gage 625 (oe a Wave Period, Tp: sec Gage 625 oe a Water Level from NGVD, m Gage 1 ee YES ONE We EA Ly LL Lh OP 18 19 20 21 APRIL 1988 Figure 35. Data for 19 April 1988 storm 66 3-5 June 1988 (Figure 36) 74. This small coastal storm developed off Cape Hatteras, NC, early on 3 June and rapidly moved offshore. Maximum onshore winds (from north- northeast) exceeded 15 m/sec at 1934 EST on 3 June. This was closely followed by the maximum H,, (Gage 625) of 2.40 m ( T, = 7.53 sec). Also on 3 June, the minimum atmospheric pressure of 1005.3 mb was recorded at 0842 EST. Total precipitation was 27 mn. 1040 Atmospheric Pressure, mb Gage 616 1030 1020 1010 7s eI Er aa a oro 1000 990 = 25 Wind Speed, m/sec Gage 632 20 15 10 5 oO 1 360 Wind Direction, Deg True N Gage 633 270 180 90 0 =i 150 Wave Direction, Deg True N Gage 21 Wave Height, H,,5,™ Gage 625 Wave Period, Tp. sec Gage 625 0 2 Water Level from NGVD, m Gage 1 1 0 Talesteotolen [alles tesle alla aa allan alain og lator] 4 5 6 JUNE 1988 Figure 36. Data for 3-5 June 1988 storm 67 4 October 1988 (Figure 37) 75. On 3 October, this storm developed in the Gulf of Mexico off the Florida coast, quickly intensified as it moved up the eastern coast, and was located off Cape Hatteras, NC, early on 4 October. By the morning of 5 Octo- ber, it was located off the New England coast. Maximum winds (from north- northeast) exceeding 16 m/sec peaked at 1000 EST on 4 October, and the maximum Hig (Gage 625) of 2.29 m Ge = 6.56 sec) was recorded at 0842 EST on the same day. The minimum atmospheric pressure of 1008 mb was recorded at 0/00 EST on 4 October. Total precipitation was 25 mm. Atmospheric Pressure, mb Gage 616 Gage 632 3 Wave Height, H,,,.™m Gage 625 ie lee ie pe ee 25 Wave Period, Tp» sec Gage 625 0 2 Water Level from NGVD, m Gage 1 1 0 LEE] [oe a Pn og Lea LT 3 4 5 6 OCTOBER 1988 Figure 37. Data for 4 October 1988 storm 68 8 October 1988 (Figure 38) 76. Following the small storm on 4 October, winds continued onshore. With the addition of a strong Canadian high pressure system on 7 October, waves briefly exceeded 2 m. Maximum wind speeds (from north) recorded on 7 October exceeded 13 m/sec at 1334 EST; maximum H,, of 2.07 m (T, = 6.92 sec) at Gage 625 occurred at 0208 EST on 8 October. 1040 Atmospheric Pressure, mb Gage 616 25 Wind Speed, m/sec Gage 632 10 5 ———sra| Wind Direction, Deq True N Gage 633 150 Wave Direction, Deg True N Gage 21 3 Wave Height, H,,,,™m Gage 625 Ua 25 Wave Period, T,, sec Gage 625 0 ee 5 0) 2 Water Level from NGVD, m Gage 1 1 C) UU UM aU ae P| 8 9 10 OCTOBER 1988 Figure 38. Data for 8 October 1988 storm 69 1 November 1988 (Figure 39) 77. Forming off the Georgia coast early on 1 November, this storm moved rapidly past the FRF and was located off New England by the next day. Maximum onshore winds (from northeast) peaked near 11 m/sec at 0208 EST on 1 November. At 1442 EST the maximum H,, (Gage 625) of 2.41 m(T, = 6.92 sec) was recorded, and at 1600 EST the minimum atmospheric pressure of 1003.3 mb was recorded. Total precipitation was 30 mm. 1040 Atmospheric Pressure, mb Gage 616 1030 1020 1010 1000 990 al 25 Wind Speed, m/sec Gage 632 20 15 10 5 ° = 360 Wind Direction, Deg True N Gage 633 270 180 90 s ae i) =a 1505 Wave Direction, Deg True N Gage 21 90 vl -30-4 35 Wave Height, Hj, Gage 625 2 Cea a es Se Sac os Os o+- 1 25 Wave Period, Tp sec Gage 625 6 ———_———— 0 1 2 Water Level from NGVD, m Gage 1 1 0) —— -1 —2 T Tis T T Te T T T T T WIS es eT T T rT Vrarect: 1, T T 1 1 2 3 NOVEMBER 1988 Figure 39. Data for 1 November 1988 storm 70 24 November 1988 (Figure 40) 78. Forming in the Gulf of Mexico, Tropical Storm Keith slowly followed a cold front across Florida on 22-23 November and continued to move to the northeast into the Atlantic on 24 November. The combination of a strong Canadian high pressure system and this offshore tropical storm produced storm waves on the 24th. Maximum onshore winds (from north-northeast) reached 14 m/sec at 0208 EST on the 24th followed shortly (0400 EST) by the minimum atmospheric pressure of 1010.1 mb. The maximum H,, (Gage 111) of 2.47 m ( T, = 7.30 sec) was recorded at 1600 ESt. There was no precipitation. 1040 Atmospheric Pressure, mb Gage 616 1030 1020 1010 1000 990 ; =a 25 Wind Speed, m/sec Gage 632 20 15 10 a 0 1 Wind Direction, Deg True Gage 633 2 SO Soe 4 Wave Height, lina) Gage 111 3 2 eee ee t) 25 + Wave Direction, Deg True N Gage 21 Gage 111 10 0 2 Water Level from NGVD, m Gage1 i 1 C) GI ee Ey A 2 A AN NS aaa a 23 24 26 NOVEMBER 1988 Figure 40. Data for 24 November 1988 storm 71 4 December 1988 (Figure 41) 79. A strong high pressure system centered over the southeastern United States in combination with a storm located in Canada produced strong winds on 4 December. Maximum winds (from north-northwest) exceeding 15 m/sec were recorded at 1034 EST on 4 December, and at 1142 EST the maximum H,, (Gage 111) of 2.29 m ( T, = 7.31 sec) was recorded. Atmospheric Pressure, mb Gage 616 A a ee a Rely tah tigen ee Wind Speed, m/sec Gage 632 380 Wind Direction, Deg True N Gage 633 270 1804 904 o4 1 ED) Wave Direction, Deg True N Gage 21 "= yee ee 304 -30- 1 Wave Height, H,,,,™ Gage 111 24 / 14 ee Ga ey (he 1 25 Wave Period, Tp: sec Gage 111 20 15 - eae ere a es ee : NS ie) = al 2 Water Level from NGVD, m r Gage 1 1 ° ee ae ee “1 -2 14 15 16 7 18 DECEMBER 1988 Figure 41. Data for 4 December 1988 storm 72 15-16 December 1988 (Figure 42) 80. A strong storm located well offshore followed a track parallel to the east coast and generated northerly winds that peaked in excess of 13 m/sec at 0242 EST on 16 December. At 0542 EST that same day, maximum H,, (Gage 111) of 2.34 m (T, = 14.22 sec) was recorded. Because the storm remained well offshore, the atmospheric pressure was only slightly affected. There was no precipitation. 1040 Atmospheric Pressure, mb Gage 616 1020 a = a = ea Sea 25 Wind Speed, m/sec Gage 632 20 15 10 5 0 71 360 Wind Direction, Deg True N Gage 633 270 180 90 te) 1 150 Wave Direction, Deg True N Gage 21 90 30 -30 3 Wave Height, H,,,,™m Gage 111 2 a 1 7 25 Wave Period, Tp, sec Gage 111 20 15 10 5 0 1 2 Water Level from NGVD, m Gage 1 1 ° SS -1 -2 LS Cn ree een om pmo LS F alpeat ont T LoL LUE | LA T T Ly T T Tt Toot 3 4 5 6 DECEMBER 1988 Figure 42. Data for 15-16 December 1988 storm REFERENCES Bingham, C., Godfrey, M. D., and Tukey, J. W. 1967. "Modern Techniques of Power Spectrum Estimation," IEEE Trans. Audio Electroacoustics, AU-15, pp 56- 66. Birkemeier, W. A., and Mason, C. 1984. "The CRAB: A Unique Nearshore Surveying Vehicle," Journal of Surveying Engineering, American Society of Civil Engineers, Vol 110, No. 1. Field Research Facility. 1988 (Jan-Dec). "Preliminary Data Summary," Monthly Series, Coastal Engineering Research Center, US Army Engineer Waterways Experiment Station, Vicksburg, MS. Grogg, W. E., Jr. 1986. "Calibration and Stability Characteristics of the Baylor Staff Wave Gage," Miscellaneous Paper CERC-86-7, US Army Engineer Waterways Experiment Station, Vicksburg, MS. Miller, H. C. 1980. “Instrumentation at CERC’s Field Research Facility, Duck, North Carolina," CERC Miscellaneous Report 80-8, US Army Engineer Waterways Experiment Station, Vicksburg, MS. Miller, H. C., Birkemeier, W. A., and DeWall, A. E. 1983. "Effect of the CERC Research Pier on Nearshore Processes," Coastal Structures '83, American Society of Civil Engineers, Arlington, VA, pp 769-785. US Department of Commerce. 1988. "Daily Weather Maps," Weekly Series, Washington, DC. Welch, P. D. 1967. "The Use of Fast Fourier Transform for the Estimation of Power Spectra: A Method Based on Time Averaging Over Short Modified Periodograms," IEEE Trans. Audio Electroacoustics, AE-15, pp 70-73. 74 APPENDIX A: SURVEY DATA 1. Contour diagrams constructed from the bathymetric survey data are presented in this appendix. The profile lines surveyed are identified on each diagram. Contours are in half meters referenced to National Geodetic Vertical Datum (NGVD). The distance offshore is referenced to the Field Research Facility (FRF) monumentation baseline behind the dune. 2. Change in FRF bathymetry diagrams constructed by contouring the dif- ference between two contour diagrams are also presented with contour intervals of 0.25 m. Wide contour lines show areas of erosion. Other areas correspond to areas of accretion. Although these change diagrams are based on consider- able interpolation of the original survey data, they do facilitate comparison of the contour diagrams. Al 850 wate ORO RY SOX ROOY LORY BERRY RY 9 Dec 87 0.25 m contours FRF Pier co) ) S a) n o D S 5 aS O SRR SRR E RS S 1o) fe 9 ne +O a “- (2) 2 © wo ry a ° Db o < \ S 5 d w Soh 456 WloRysoun. SOmeiorne ket. Eo) pec bamanmaes b = ° a Ce) nn © no + ” a = = 0 a qd wi ‘aouDtsig Y Ww) Ga 'p A, Oo) ue) Ss foe) os) > ) 5 So u a da) 2 0) & N > u b rk o 2 a a de) p E BS o Q ce = fey fo) oe o 2 ay SIS) < i) uy >} & di fy io} i's) N Oo wo 1100 1000 900 800 700 600 500 400 300 200 100 -100 lu ‘a9UuDISsIG A2 FRF Pier ° fo) = ate x x. 1000 r> QS SRA > ARN ‘ RRR) ie 2 Feb 88 0.25 m contours oO Oo aS a) n oO D S ce) iS S) 1000 900 800 600 500 lu ‘aouDdIsigq A3 600 FRF Pier 500 400 300 650 850 Distance, m 450 250 50 -100 650 850 450 50 -100 Distance, m Figure A2. FRF Bathymetry 30 March 88 (depths relative to NGVD) FRF Pier 850 oO 7) Oo 5 = = E'@ 7a) = c ” ° oO =O © Do £ © 5M N 2 : O o ma > 2 o wo N =< = \ = 2 °o o Co oO o oOo oOo oOo o oO oOo o o Ww ° ° o ° ° f—) ° o ° ° o o = ° a © x © rte) ~ ay a = = lu ‘aouDd}sig SAAQUWINN SUIT A]!fJodd no on Oo Reto - De) o 0 fo) -e) N o Le) wo Te) oO a) i fra) EO LOS Ses eS 2 2 es) oy °o o te) ° 0 o ° 0 t ° 0 N °o 0 1100 1000 900 800 700 600 500 400 300 200 100 WW ‘aouUDIsig A4 Distance, m Distance, m FRF Bathymetry 21 April 88 (depths relative to NGVD) Figure A3. ine ° ! oO i) pS / oO “ ® ' RY Se as ORY oO 2 a . i RY Y ” reais re & Y RY ”naQo RRR % oq? rs i RRR (a D E Se ARR Sa RSH) ROX) (= Oo RRR op ee) ® ARR) wer o SRR SD ey ons eS NNN AS g 5 BASIN y be \ a ° “-™~ (=) a > oO a ° p o = ara = 2 ° ° ° ° ° ° ° ° ° ° ° ° o o w ° ° o ° ° ° ° ° ° ° ° o > = ° a Cs) n o w ~~ i) “ - = ord 2 1 b lu ‘a0uDd}sig pr oO te] n G p SIAQGWINN Ul] df!foud 2 mo nO Se Gy cy ee el SCD) ee) onan +t O Dm Oo WY WwW MOR OMe wo! ot Ran oom on Oe SSeS USS = AUS A SOC gS a atet eh oo x (oe) roe) o ° 5 wo re) =) [o) > HW b o . Es v4 G © yp ise} ¢ ceo % = > > ie) ° a wo . ° bp 5 o ms ® eh w S| 0) u a) G p A, o U0 4 SUSGUINN aul] af!}Joudg m [o) man we NT tO) Tin CON TS COO Oe OD MRANATORMNON OD HHO Ty iss tp net eine CO) GONE TOO CO, (CONGO uel) io) nn © © OO OR ROOD |—- — | & BS aes fy SS) OE iS SS SS ES aa 2 i= oO 2 8 © a ad N > MY b o {S) as rd G p Se 8 o Qo fd Ss {) RS ( co SRS SSSR Renin SOS °o Ky 9 1 o wo N is fo} o wo o oO oO oO oO o i=) °o o °o o oO o Ww ° ° rs) ° ° ° ° ° ° ° ° o = o an te) Lad wo wo Tt Le) N od ai lu ‘aouDIsig SUAQUWINN UIT a!youg mo 0 Oo Sie o- NM NO KR DDO 0oOAN tT ORM O WY WY TOBIN ER OICON (w) Ub! IRS IS) cok oy ee, te SSS sr a SS SS ee eed Oo 0 te) ° 0 o ° 7) vt ° wo N ° wo Oo Oo oO oO Oo oO oO o Oo Oo Oo oO o Oo oO Oo oO Oo Oo Oo Oo Oo oO Oo oO = ° roy rs) i © Te) + rm N = 7 lu ‘aouUDIsIg AQ Distance, m Distance, m Figure A8. FRF Bathymetry 19 December 88 (depths relative to NGVD) Lofts ee ” i = i oa ) : i pe tie j i na i ey i ran | mnie eer seo iets aes ee } F DAY Ta) vin eS Bh ins bolls 2 oe” Pe La) _ —iepe ost, Prd conte al 5 pity sneer) meals ene itt ed AM APPENDIX B: WAVE DATA FOR GAGE 630 1. Wave data summaries for Gage 630 are presented for 1988 and for 1980 through 1988 in the following forms: Daddy ee eeatid eal 2. Figure Bl displays the individual wave height and peak spectral wave period values along with the monthly mean values. Joint Distributions of H,, and T, 3. Annual and monthly joint distributions tables are presented in Tables Bl and B2, and data for 1980 through 1988 are in Tables B3 and B4. Each table gives the frequency (in parts per 10,000) for which the wave height and peak period were within the specified intervals; these values can be converted to percent by dividing by 100. Marginal totals are also included. The row total gives the total number of observations out of 10,000 which fell within each specified peak period interval. The column total gives the number of observations out of 10,000 which fell within each specified wave height interval. Cumulative Distributions of Wave Height 4. Annual and monthly wave height distributions for 1988 are plotted in cumulative form in Figures B2 and B3. Data for 1980 through 1988 are in Figure B4. Peak Spectral Wave Period Distributions 5. Annual and monthly peak wave period, T, , distribution histograms for 1988 are presented in Figures B5 and B6. Data for 1980 through 1988 are in Figure B/7. Bl Persistence of Wave Heights 6. Table B5 shows the number of times in 1988 when the specified wave height was equaled or exceeded at least once during each day for the duration (consecutive days). Data for 1980 through 1988 are given in Table B6. An example is shown below: Height Consecutive Day(s) or Longer emt EA he NS IASG HET) SES MEO MMO Mh ey PAST a ae PALE Se Ags 0.5 18 15 1 ee TO) We) ne 8 q 1.0 SOSAe eared) ASuulGaudel am Sany sees 2 155 AOE 8) aOr acai 2.0 22) Oe Shunt 2.5 10mm Sie 3.0 Gt 325 1 4.0 1 This example indicates that wave heights equaled or exceeded 1.0 m 50 times for at least 1 day; 34 times for at least 2 days; 24 times for at least 3 days, etc. Therefore, on 16 occasions the height equaled or exceeded 1.0 m for 1 day exactly (50 - 34 = 16); on 10 occasions for 2 days; on 3 occasions for 3 days, etc. Note that the height exceeded 1 m 50 times for 1 day or longer, while heights exceeded 0.5 m only 18 times for this same duration. This change in durations occurred because the longer durations of lower waves may be interspersed with shorter, but more frequent, intervals of higher waves. For example, one of the times that the wave heights exceeded 0.5 m for 16 days may have represented 3 times the height exceeded 1 m for shorter durations. Spectra 7. Monthly spectra for the offshore Waverider buoy (Gage 630) are presented in Figure B8. The plots show "relative" energy density as a function of wave frequency. These figures summarize the large number of spectra for each month. The figures emphasize the higher energy density associated with storms as well as the general shifts in energy density to different frequencies. As used here, "relative" indicates the spectra have been smoothed by the three-dimensional surface drawing routine. Consequently, extremely high- and low-energy density values are modified to produce a smooth B2 surface. The figures are not intended for quantitative measurements; however, they do provide the energy density as a function of frequency relative to the other spectra for the month. 8. Monthly and annual wave statistics for Gage 630 for 1988 and for 1980 through 1988 are presented in Table B/7. 9. Figure B9 plots monthly time histories of wave height and period. B3 Wave Height, m Wave Period, sec 5.0 4.0 Year Mean, m *— 1988 1.0 0.0 JAN FEB 20.075 — inet If wale T TEL T Til; T mapa 1 MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Month Year Mean, sec *—x 1988 8.0 JAN FEB Figure Bl. eS soa =] fon Tena moe T praia lneereeas ts ilcapueceal| MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Month 1988 daily wave height and period values with monthly means for Gage 630 B4 Table Bl Annual Joint Distribution of H,, Height(m) 2.0- 3.0- (Ae) SSG) 4.0- 4.9 5.0- 5.9 Annual 1988 Percent Occurrence(X100) 6.0- 6.9 Gage 630 of Height and Period Per iod(sec) 10.0- 12.0- 14.0- 16.0- versus T Pp ° PWWNNRPROCO ee eusemieltelreltomts POPOFPOLO-, OWOWONDNDVODOUOWO ° PRPWWNNRRrOO oe ee eo ew we ww uo oO Oo Cet Oo Dele > wo o Greater 7.0- 8.0- 9.0- 7.9 8.9 ~9.9 96 301 301 610 1051 904 221 206 199 74 110 74 44 51 15 7 : 15 22 u 7 ° 15 : ° uy ° . ° Uf 1074 1748 1522 B5 213 463 Total Table B2 Monthly Joint Distribution of H,, versus T, January 1988, Gage 630 Percent Occurrence(X100) of Height and Period Height(m) Period(sec) Total 2.0- 3.0- 4.0- 5.0- 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 2-95 3290 4.9 0 5.90 16595 729) 18.9 019.9) 19) 413).9) 6 159. Fongern 0.00 - 0.49 5 9 O 81 4 6 81 161 242 242 807 0.50 - 0.99 81 161 (242 1403 «403° AGI.) 161. 1242)> 1887. 4242) 242) 3225 1.00 - 1.49 5 242 484 565 81 323 565 806 3 81 3147 1.50 - 1.99 6 } 81 1048 161 161 81 242 161 812) 161 2177 2.00 - 2.49 6 6 C os) BLL 61) 6 81 6 403 2.50 - 2.99 5 é 5 4 81 g 5 . 3 b 81 3.00 - 3.49 3 6 6 a c 81 81 C 3 5 ° 162 3.50 - 3.99 0 6 6 . a ° o S 5 4 5 5 0 4.00 - 4.49 O 5 5 3 ° 6 6 5 5 6 0 4.50 - 4.99 6 6 e 3 O 5 5 O 0 6 0 5.00 - Greater 9 . ° 5 3 5 * . . 6 4 Z 0 Total 81 161 565 2016 1371 645 727 1130 2015 565 726 0 February 1988, Gage 630 Percent Occurrence(X100) of Height and Period Height(m) Per iod(sec) Total 2.0- 3.0- 4.0- 5.0- 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 2.9 359) 4.9 5-9 6.9 7.9) 8.9) 9.9! 111.9) 11339-01559 Longer: 0.00 - 0.49 O A 2 86 5 O 5 86 86 172 430 0.50 - 0.99 345 172 603 948 172 86 690 1121 776 3 4913 1.00 - 1.49 6 e259) 517, 259) 259; 7/2) 25911690 Q : 7 2415 1.50 - 1.99 3 G 172, S17" 9172; (259 86 259 3 . 1465 2.00 - 2.49 0 ° 5 tye a2 ° 86 86 o 6 86 é 602 2.50 - 2.99 0 e 5 86 6 9 6 86 5 é 6 G 172 3.00 - 3.49 0 5 5 6 5 6 0 O 5 : 0 3.50 - 3.99 5 O 5 6 6 6 5 3 0 4.00 - 4.49 6 ; 5 7 6 3 9 0 O 5 O 3 0 4.50 - 4.99 6 : 3 0 C 5 & . 5 6 0 5.00 - Greater 2 9 b C 2 3 . ° : 5 4 0 Total 45 172 862 1981 1120 517 1207 1638 1811 86 258 0 March 1988, Gage 630 Percent Occurrence(X100) of Height and Period Height(m) Per iod(sec) Total 2.0- 3.0- 4.0- 5.0- 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 2.9) 22329) 49) 5/9) 69) 07:09) 18.9) NSO) tS 9 e519 Longer 0.00 - 0.49 c 3 : 83 c a 83 0.50 - 0.99 6 83 83 826 1074 413 579 1736 1488 : , 6282 1.00 - 1.49 . 331 661 6615413331) 165)9 sl 6 6 2893 1.50 - 1.99 C : 835 331165 8 2 O E : 6 662 2.00 - 2.49 o . cC 83 . C : : C 5 83 2.50 - 2.99 . . 2 A C a : : 6 6 o q 0 3.00 - 3.49 - : 7 6 c 5 6 : : 0 3.50 - 3.99 6 ; c : : ° : ; 0 cS 0 4.00 - 4.49 ; 0 . 6 C 6 : : 0 : 0 4.50 - 4.99 0 ; C . 2 . : 0 0 5.00 - Greater 5 5 - 5 9 . 0 5 0 Total 0 83 497 1901 1900 909 993 1901 1819 0 0 0 (Continued) (Sheet 1 of 4) B6 Table B2 (Continued) April 1988, Gage 630 Percent Occurrence(X100) of Height and Period Height(m) Period(sec) Total 2.0- 3.0- 4.0- 5.0- 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 2.9 3.9 4.9 5.9 6.9 (7.9 18.9 (9.9 11.9 13.9 15.9 Longer 0.00 - 0.49 3 b O 5 A a. Belz. ° 86 258 0.50 - 0.99 86 345 603 345 690 603 86 1293 1034 345 776 6206 1.00 - 1.49 4 f Spel 2259259 86 9517 172 2 1465 1.50 - 1.99 é oelee 3 86 3 172) 9345 ' 775 2.00 - 2.49 . é 5 3 5 Yr e259 Q 431 2.50 - 2.99 6 6 c 5 8 3 A 86 B C 86 258 3.00 - 3.49 6 0 C 6 a aby 5 86 O ° 3 . 258 3.50 - 3.99 0 é 3 5 a arline. é G 6 2 : 172 4.00 - 4.49 6 . 3 : 5 5 86 C 5 : 6 6 86 4.50 - 4.99 6 5 C 6 A < 4 86 é . 5 3 86 5.00 - Greater 3 6 9 o ° C 5 5 C c 9 0 Total 86 345 603 689 1035 1120 602 2412 1810 431 862 0 al 1988, Gage 630 Percent Occurrence(X100) of Height and Period Height(m) Per iod(sec) Total 2.0- 3.0- 4.0- 5.0- 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 2-9). 1359 64:9 | 5.9 96.91'007.9 . 8.9' 179.9 211.9 113-69 15.9 )iLonger, 0.00 - 0.49 5 : A 90 5 = 450) 270 3 & : 810 0.50 - 0.99 7 c = 9270) 4360) ¥633 1802) 12261 $8721 7 90 é 5135 1.00 - 1.49 ° > 3 2220) \ 2700 8450) W721) 180) - 541 é 6 2432 1.50 - 1.99 : : - 180 180 360 180 541 C 4 o 1441 2.00 - 2.49 é 5 c A 90 9 . c 6 : 6 & 180 2.50 - 2.99 a 5 Cl . C 3 4 é Gi : 6 0 3.00 - 3.49 : 6 5 3 : c 6 ; c o : 0 0 3.50 - 3.99 : 6 5 3 ‘ 6 6 6 c & : : 0 4.00 - 4.49 6 6 i 5 . 4 6 . 6 < : C 0 4.50 - 4.99 5 6 5 5 6 5 : : 3 : : 3 0 5.00 - Greater . 5 c 2 A ° S ° A 6 é 5 0 Total 0 0 0 630 900 1351 3333 1891 1803 0 90 0 June 1988, Gage 630 Percent Occurrence(X100) of Height and Period Height(m) Period(sec) Total 2.0- 3.0- 4.0- 5.0- 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 5.9 7.9 2<9nrss9e 49 6.9 8.9 9.9 11.9 13.9 15.9 Longer 0.00 - 0.49 99 99 99 297 99 693 891 792 Q - 198 ; 3267 0.50 - 0.99 198 495 - 990 1980 990 297 5 é 4950 1.00 - 1.49 5 5 99 a el 99 0 99 6 5 ° 693 1.50 - 1.99 O ° 99 99 99 O J - » 198 : 99 6 594 2.00 - 2.49 G 6 5 . 99 99 297 : O : 0 7 495 2.50 - 2.99 : : 5 6 5 3 G : 5 C O 6 0 3.00 - 3.49 5 5 0 c 5 9 6 6 . 7 0 3.50 - 3.99 2 5 6 ° C 5 5 5 6 0 0 4.00 - 4.49 2 . 0 6 0 ° 3 5 z 5 0 4.50 - 4.99 5 . 6 6 O 3 6 5 o 5 0 5.00 - Greater . 6 O * 7 4 5 0 A A 9 : 0 Total 99 297 792 396 693 1881 3168 1782 594 0 297 0 (Continued) (Sheet 2 of 4) B7 Table B2 (Continued) Height(m) 0.00 - 0.49 0.50 - 0.99 1.00 - 1.49 1.50 - 1.99 2.00 - 2.49 2.50 - 2.99 3.00 - 3.49 3.50 - 3.99 4.00 - 4.49 4.50 - 4.99 5.00 - Greater Total Height(m) 0.00 - 0.49 0.50 - 0.99 1.00 - 1.49 1.50 - 1.99 2.00 - 2.49 2.50 - 2.99 3.00 - 3.49 3.50 - 3.99 4.00 - 4.49 4.50 - 4.99 5.00 - Greater Total Height(m) 0.00 - 0.49 0.50 - 0.99 1.00 - 1.49 1.50 - 1.99 2.00 - 2.49 2.50 - 2.99 3.00 - 3.49 3.50 - 3.99 4.00 - 4.49 4.50 - 4.99 5.00 - Greater Total Period(sec) Total 2.0- 3.0- 4.0- 5.0- 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 2.9 3.9 4.9 5.9 6.9 7.9 8.9 9.9 11.9 13.9 15.9 Longer . 6 C 83 - 165 909 744 248 ° . : 2149 83 248 83 826 1074 1405 2562 992 165 6 83 ; 7521 5 5 ° 83 248 5 5 5 > 0 6 . 331 5 . ° . . ° ° e ° 5 4 5 0 * 5 6 . - . fe ° ° 4 5 . 0 . . ° a 5 ° 5 5 O 5 5 6 0 5 = 5 . . A 4 6 6 . 0 O 0 A 6 6 . O b ° ° 6 4 . 6 0 . 3 J . . O 5 é Q . . J 0 e ° * . ° . ° ° ° . A O i 83 248 83 992 1322 1570 3471 1736 413 0 83 0 August 1988, Gage 630 Percent Occurrence(X100) of Height and Period Per iod(sec) Total 2.0- 3.0- 4.0- 5.0- 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 2.9 3.9 4.9 5.9 6.9 7.9 8.9 9.9 11.9 13.9 15.9 Longer 84 5 84 336 84 a ckt) 84 a 5 : 3 1008 5 - 252 1092 1092 1261 2101 756 an CE} 84 6 6974 6 5 84 1008 58 - 168 84 6 6 5 6 1932 ° 5 5 84 . o c a 0 5 O : 84 6 - 5 co ° D 5 O 5 ° G 5 0 7 6 5 ° 7 6 - O O 6 5 0 ° C 5 0 5 ° . 5 O 5 0 Q 0 6 : ; : ; ; ‘ 6 : 6 ; ; 0 7 ° O q 6 5 O a 0 o 6 ; 0 3 5 7 3 6 6 o 5 C ° 7 O 5 84 0 420 2520 1764 1261 2605 924 0 336 84 0 September 1988, Gage 630 Percent Occurrence(X100) of Height and Period Per iod(sec) Total 2.0- 3.0- 4.0- 5.0- 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 5 3.9 4.9 5.9 6.9 7.9 8.9 9.9 11.9 13.9 15.9 Longer 90 5 5 2 90 2 90 360 90 6 0 D 720 C - 270 1171 450 991 721 1081 180 - 360 O 5224 5 ° 90 631 721 360 270 5 90 270 360 6 2792 0 . 9 450 450 90 180 O . A O 3 1170 o b 7 5 90 Q 0 . 0 6 O 9 90 C 3 ; 5 3 6 0 0 6 a : c 0 . 5 ° 3 0 C 5 0 6 . Cc a 0 c c 6 5 : 6 3 O cC . é G 0 O < ° 5 . J 5 6 é O ; 6 0 0 6 . 6 é C A : ; d : g 0 6 360 2252 1801 1441 1261 1441 360 270 720 0 (Continued) July 1988, Gage 630 Percent Occurrence(X100) of Height and Period B8 (Sheet 3 of 4) Table B2 (Concluded) Height(m) Period(sec) 2.0- 2.9 0.00 - 0.49 93 0.50 - 0.99 93 1.00 - 1.49 é 1.50 - 1.99 : 2.00 - 2.49 : 2.50 - 2.99 b 3.00 - 3.49 : 3.50 - 3.99 5 4.00 - 4.49 A 4.50 - 4.99 : 5.00 - Greater 6 Total 186 2.0- ° ao oo =) Oo 00° Oe eBid ° OPRPWWNNRRrOO ORieMehamemeemelicne on Oo WWNNEROO ee © once OWODNDNOHOOW ° 2.0- 2.9 0.00 - 0.49 678 0.50 - 0.99 : 1.00 - 1.49 G 1.50 - 1.99 : 2.00 - 2.49 2.50 - 2.99 3.00 - 3.49 6 3.50 - 3.99 A 4.00 - 4.49 6 4.50 - 4.99 6 5.00 - Greater 3 Total 678 3.0- 3.9 3.0- 3.9 319 3.0- 3.9 October 1988, Gage 630 Percent Occurrence(X100) of Height and Period 4.0- 4.9 371 Percent Occurrence(X100) of He Height(m) Per iod(sec) 4.0- 4.9 5.0- 5.9 5.0- 5.9 6.0- 6.9 6.0- 6.9 December 1988, Gage 630 Percent Occurrence(X100) of Height and Period Height(m) Per iod(sec) Tot 4.0- 5.0- 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 4.9 5.9 6.9 7.9 8.9 9.9 11.9 13.9 15.9 Longer Total 72020'6.02). 9:05 110.02912-0- 14.0- 16.0- 7.9 8.9 9.9 11.9 13.9 15.9 Longer 93 278 278 556 278 : 1576 . 648 648 1759 278 278 ; 4352 hgh) 278 06278 . 833 ; 2501 ith o7 8 eet93) 10370) 93 : ; 1204 93 93 : 3 i ; ; 279 ; : f ; x % 93 186 1390 1297 2963 371 1389 0 November 1988, page 630 ght and Period Total 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 7.9 8.9 9.9 11.9 13.9 15.9 Longer 319 319 213 A OSNERO) y 1276 532 638 106 i : : : 3829 532 213 213 106 ; : ; 3830 106 213 106 5; ; i : 744 106 5 : : , : c 318 5 j : ; : 0 3 3 : : é 0 ; : . : ‘ ; 0 1595 1383 638 106 106 319 0 - 254 763 85 85 2373 254 678 508 508 169 339 4151 254 85 85 85 85) 169 2119 ° ° . . 85 169 1102 . . . . . ° 169 85 . . . . . 85 . . . ° . ° 0 . . . . . ° 0 . . . . . ° 0 . . . . . ° 4 593 1017 1356 678 339 762 0 (Sheet 4 of 4) B9 OP RPWWNNPrrOO ele Dol lepein el elien em omic Table B3 Annual Joint Distribution of H,, Height(m) ° oO oO ete De Th th De Del) WWNNRPRrOO chicietetcelcs ° OPOPOLRO OWDODWDODHOUOW Percent Occurrence(X100) of Heigh versus Tp Annual 1980-1988, Gage 630 (All Years) and Period Period(sec) 2.0- 9 3.0- 3.9 4.0- 4.9 5.0- 5.9 nae 12.0- 14.0- 16.0- 6.0- 7.0- 8.0- G9) i799, 94 115 328 572 515 860 451 264 246 256 109 79 78 74 49 9 32 17 1 9 15 1 5 2 2 3 1 1461 1119 1602 B10 9.0- 9.9 281 200 717-812 200 360 70 = =139 41 70 16 38 14 17 7 10 2 7 i 3 1349 1656 i) = w ry PPP (Oe e© © © © © AY a w a nN Monthly Joint Distribution of H,, Height(m) OODWNDNHONWOUOW . OMNoMononoWo Soletololojojojeloy~) UUs (i= te estb Ue Te sy OP RPWWNNRROO eke meme Outs OGL CEs6 Height(m) 0.00 - 0.49 0.50 - 0.99 1.00 - 1.49 1.50 - 1.99 2.00 - 2.49 2.50 - 2.99 3.00 - 3.49 3.50 - 3.99 4.00 - 4.49 4.50 - 4.99 5.00 - Total Height(m) 0.00 - 0.49 0.50 - 0.99 1.00 - 1.49 1.50 - 1.99 2.00 - 2.49 2.50 - 2.99 3.00 - 3.49 3.50 - 3.99 4.00 - 4.49 4.50 - 4.99 5.00 - Total Percent Occurrence Table B4 Bll versus January 1980-1988, Gage 630 ¢x100) of Heigh T (All Years) and Period Per iod(sec) 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 659) 207.9!) 0859) 25939 E119) S359 $1559) Aonger: 32 168 84 221 63 105 347 305 495 874 116 253 = 221 168 179 589 74 11 232 95 116 242 21 63 . 221 95 32 126 42 32 11 84 53 21 42 21 5 5 alal 32 ual 32 5 , i a pet ; O 6 11 . S 1148 916 938 2148 263 580 22 February 1980-1988, Gage 630 Percent Occurrence(X100) of Height and Period Period(sec) 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 6.9 7.9 8.9 9.9 11.9 13.9 15.9 Longer 22 88 5 44 330) 133 5 243 541 685 1116 22 144 11 232 298 354 £608 88 221 O 199 110 99 221 66 110 5 22 44 88 99 55 110 3 33 5 Le 122: 22 66 * 11 5 22 33 11 22 o - 11 11 o O 6 o abit 33 4 6 O Banas ‘ i : ; : 762 1092 1281 2287 297 806 11 March 1980-1988, Gage 630 Percent Occurrence(X100) of Height and Period Period(sec) 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 6.9 7.9 8.9 9.9 11.9 13.9 15.9 Longer 50 80 40 120 60 60 5 A2Te Ss 5215 7 772) 872) 150) 7 180 6 341. 7 281i 9 301% 711 60 331 6 100 80 100 251 90 140 30 70 50 160 40 110 10 10 10 60 20 50 . 10 20 50 10 10 5 & 20 20 5 10 - 10 10 10 20 c 5 O 20 o 0 952 1062 1323 2274 430 911 0 (Continued) (Sheet 1 of Total Total Total Height(m) . OMNONONMNOWOWN0 ACOOCOCCCCO0C00Co o UP RPWWNNRRHOO euMela esters ieienie =—|DPPWWNNRPROO omeediestententeuxeiieGienie ~ o Gull {to Ue ee pos 0 a om Height(m) 0.00 - 0.49 0.50 - 0.99 1.00 - 1.49 1.50 - 1.99 2.00 - 2.49 2.50 - 2.99 3.00 - 3.49 3.50 - 3.99 4.00 - 4.49 4.50 - 4.99 5.00 - Greater Total Height(m) 0.00 - 0.49 0.50 - 0.99 1.00 - 1.49 1.50 - 1.99 2.00 - 2.49 2.50 - 2.99 3.00 - 3.49 3.50 - 3.99 4.00 - 4.49 4.50 - 4.99 5.00 - Greater Total Period(sec) Total 2.0- 3.0- 4.0- 5.0- 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 209) 9359) 1459) 955911659979 829) 9.9) 19) A138 15.9 Longer 4 10 21 21 31 21 308 226 185 103 103 d 1029 92) 195) 267) 69390) 503) 1513) 5 677,5 697) 128287 421 5 5170 a 10 103 226 369 318 328 287 369 62 154 ; 2226 e 6 2 9144 123 92 92 113 215 si S113 é 923 Q 5 . 41 31 10 51 62 62 31 10 5 298 5 3 5 5 10 21 31 21 41 31 21 5 176 5 A 5 P C 31 21 31 31 a M 0 114 . 3 A 4 O 10 41 5 J O 6 a 51 0 5 5 4 Q 10 5 d d 3 a 10 3 5 O ° 5 O 6 10 a 3 8 5 10 3 0 6 9 5 Q 9 3 4 9 O 5 0 92 215 391 822 1067 1016 1559 1447 2031 545 822 0 May 1980-1988, Gage 630 Percent OccurrencetX100) of Height and Period Per iod(sec) Total 2.0- 3.0- 4.0- 5.0- 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 229he 359) 0429) 255910 16 9)07..9 089099) 119 1359015. 9 longer 10 20 31 92), 132) 163 77448 6 725453153 20 61 5 1384 202 153) 326 1621), 560) 0071221312) 1099 712 31 163 : 5709 : é 92 234 336 224 448 193 336 10 92 : 1965 S 5 10 51 92 41 132 81 122 31 71 0 631 i 6 « 20 20 61 : 41 10 31 31 : 214 : 6 6 10 10 10 10 10 20 10 5 80 . ‘ 5 : i 6 10 10 5 20 5 b ; : 2 3 A : 0 5 : O 6 6 6 : : 5 5 ; 0 0 6 b 0 5 3 6 6 . 5 ‘e : 30 173 459 1018 1150 1211 2350 1678 1343 153 438 0 June 1980-1988, Gage 630 Percent Occurrence(X100) of Height and Period Period(sec) Total 2.0- 3.0- 4.0- 5.0- 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- . 3. 4.9 5.9 1659) 7.9 8.99.9 (11.9. _13.9 (15.9. Longer: 32 43 65 119 227 378 636 583 205 43 32 : 2363 54 237 - 378658) “658'") °734. 11650). '895)..-757.2-. 173 32 rs 6041 6 A 76 205 227 194 194 108 108 é 54 p 1166 : 22 54 76 65 22 11 76 : 11 : 337 6 : , 22 22 43 11 6 A 6 a8 4 : ‘ : : ; : . 5 : : 0 - 6 5 é : 6 6 5 - 5 0 O 0 6 4 5 6 O 7 0 6 6 : ; 6 é . g 9 86 280 541 1036 1210 1393 2545 1608 961 216 129 0 (Continued) Table B4 April 1980-1988, Gage 630 (Continued) Percent Occurrence(X100) of Height and Period B12 (Sheet 2 of 4) Table B4& (Continued) July 1980-1988, Gage 630 Percent Occurrence(X100) of Height and Period Height(m) Period(sec) Total 2.0- 3.0- 4.0- 5.0- 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 2.9 3.9 4.9 5.9 6.9 7.9 8.9 9.9 11.9 13.9 15.9 Longer 0.00 - 0.49 11 21 53° 105 (243° «285 «1108 «791 +327 127°, 253 21 3345 0.50 - 0.99 42 137 316 643 802 781 1487 918 411 222 74 63 5896 1.00 - 1.49 C 21 53 169 190 84 53 4 C 3 . o 612 1.50 - 1.99 5 53 11 21 32 ° 5 2 117 2.00 - 2.49 : 11 O 5 11 5 7 . 22 2.50 - 2.99 : A 5 . 5 C . 0 3.00 - 3.49 G 6 5 4 5 O 5 é 0 3.50 - 3.99 } O 6 5 5 5 A Q 0 4.00 - 4.49 . 5 6 6 é 5 O . 5 0 4.50 - 4.99 0 5 q é c : 5 5 0 5.00 - Greater . c 5 : é a 9 5 9 5 z 9 0 Total 53. 179 422 981 1246 1171 2691 1751 738 349 327 84 August 1980-1988, Gage 630 Percent Occurrence(X100) of Height and Period Height(m) Period(sec) Total 2.0- 3.0- 4.0- 5.0- 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 2.9 3.9 4.9 5.9 6.9 7.9 8.9 9.9 11.9 13.9 15.9 Longer 0.00 - 0.49 32 32 74 137 179 211 474 495 369 74 105 5 2182 0.50 - 0.99 32 95 242 643 832 769 1412 790 537 190 274 . 5816 1.00 - 1.49 11 148 390 285 232 158 105 63 1 : 1403 1.50 - 1.99 G 5 (e} ale y/ 74 32 21 21 ° 32 380 2.00 - 2.49 6 . 21 21 11 21 . 42 5 11 A 127 2.50 - 2.99 é 6 11 5 21 ; 11 3 11 o 54 3.00 - 3.49 5 . 5 aay 11 : 11 5 5 5 33 3.50 - 3.99 5 : 11 6 6 0 11 4.00 - 4.49 5 ; S 5 . 0 4.50 - 4.99 5 : : ; : 5 3 3 0 5.00 - Greater a Q Q 9 6 2 A 0 G Q 6 5 0 Total 64 138 464 1254 1465 1308 2129 1422 1054 275 433 0 September 1980-1988, Gage 630 Percent Occurrence(X100) of Height and Period Height(m) Period(sec) Total 2.0- 3.0- 4.0- 5.0- 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 2.9) 3.9" 14.9 15.9" 6.9) 7.9) 8.9 9.9 11.9 13.9) 15.9) Longer 0.00 - 0.49 10 10 10 31 31 21 94 333 271 125 104 10 1050 0.50 - 0.99 : 52, 8188 "417 3583' 1521, 1813 7802 1031 4146 <250 3 4803 1.00 - 1.49 3 10 83 438 604 354 448 219 354 ke} a e/ 10 2780 1.50 - 1.99 ‘ : VO e115) 302" 8125 63) 2175 52 10 73 885 2.00 - 2.49 . A 31 83 42 21 31 73 31 21 SES) 2.50 - 2.99 6 6 5 31 21 10 5 . 62 3.00 - 3.49 6 - 5 : 6 5 10 10 10 10 40 3.50 - 3.99 9 é 4 5 c 10 10 10 30 4.00 - 4.49 C a 5 a a 6 o 5 cC 0 4.50 - 4.99 : oO 6 5 a O 3 : A 6 0 5.00 - Greater 5 5 3 Q p 5 Q g . 10 2 . 10 Total 10 72 291 1032 1603 1094 1480 1520 1801 425 645 20 (Continued) (Sheet 3 of 4) B13 Table B4 (Concluded) October 1980-1988, Gage 630 Percent Occurrence(X100) of Height and Period Height(m) Period(sec) Total 2.0- 3.0- 4.0- 5.0- oy, 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 2.9 3.9 4.9 5.9 6.9 7.9 8.9 9.9 11.9 13.9 15.9 Longer 0.00 - 0.49 29 5 48 67 202 164 260 38 144 952 0.50 - 0.99 10 38 144 337 404 375 674 481 991 173 318 10 3955 1.00 - 1.49 : e645" 5976 4337, 2120 9935 72415) 7452) B7ar 231 i 2456 1.50 - 1.99 6 o 29 192 423 Tih 77 67 202 96 212 38 1413 2.00 - 2.49 . 3 6 LOW 115s 192 58 77 =144 48 87 10 741 2.50 - 2.99 é 7 Q 0 19 125 38 58 48 10 38 C 336 3.00 - 3.49 é . 5 . S 38 10 : 10 P 29 0 87 3.50 - 3.99 5 s C ; . 0 : 19 : 19 - 38 4.00 - 4.49 : : : 3 6 19 - . 19 4.50 - 4.99 . . 5 . 5 . a . 3 6 O 0 5.00 - Greater 3 : 6 ° C . 2 S > 6 3 0 Total 39 38 337 1136 1346 1086 1194 1107 2126 471 1059 58 November 1980-1988, Gage 630 Percent Occurrence(X100) of Heigh and Period Height(m) Per iod(sec) Total 2.0- 3.0- 4.0- 5.0- 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 2.9 3.9 4.9 5.9 6.9 7.9 8.9 9.9 11.9 13.9 15.9 Longer 0.00 - 0.49 12 35 35 23 58 116 186 174 93 70 197 999 0.50 - 0.99 35 81 372 569 581 511 476 453 569 151 £139 58 3995 1.00 - 1.49 ° 23 267 569 720 453 232 244 325 2 81 35 2972 1.50 - 1.99 O 5 23 209 348 197 139 70 128 58 12 12 1196 2.00 - 2.49 C 35 ST) 390 151 46 23 23 12 : 510 2.50 - 2.99 S . o 4 23 12 23 58 : 12 : 128 3.00 - 3.49 : . 9 23 58 9 12 12 105 3.50 - 3.99 A 5 46 23 12 81 4.00 - 4.49 : : 12 : 12 4.50 - 4.99 3 5 c : : 6 A : : : 0 5.00 - Greater O : 5 0 a 9 5 5 5 O 6 5 0 Total 47 139 697 1405 1788 1439 1219 1068 1242 372 477 105 December 1980-1988, Gage 630 Percent Occurrence(X100) of Height and Period Height(m) Period(sec) Total 2.0- 3.0- 4.0- 5.0- 6.0- 7.0- 8.0- 9.0- 10.0- 12.0- 14.0- 16.0- 2.9) 93.9) (4.9) 1529) 16.59) 17.09). 18.9" 19.69 511.9) 21359" 15..9)) Longer. 0.00 - 0.49 90 34 56 79 11 23, 8035) 52370 £1355 HIS8y 8327, 11 1296 0.50 - 0.99 34 158 237 496 609 237 417 485 891 147 293 45 4049 1.00 - 1.49 6 2) GIT47, FATA> G43) 9327" 9203" 9124-4383 34) 0147, 2 2482 1.50 - 1.99 3 11, 4180" (519) =101 56 45 124 11 68 6 1115 2.00 - 2.49 6 6 23 24 135 34 56 90 45 68 : 665 2.50 - 2.99 3 0 ‘ 5 34 b 23 68 11 136 3.00 - 3.49 . 5 O 3 0 79 23 23 11 136 3.50 - 3.99 9 23 23 34 11 91 4.00 - 4.49 . ° : 11 5 11 4.50 - 4.99 : : : : 6 . 6 A : 4 ; o 0 5.00 - Greater 5 J : ; O 6 5 : 6 alal 11 9 22 Total 124 192 474 1229 1996 857 947 1016 1759 406 947 56 (Sheet 4 of 4) B14 Height, m = 419318 aes 1980-88 Figure B2. Percent Greater Than Indicated Annual cumulative wave height distributions for Gage 630 B15 Height, m 0 10m 10% 10° 10' Percent Greater Than Indicated Figure B3. 1988 monthly wave height distributions for Gage 630 B16 ~ > Height, m Mont <=: — Jan 4 SOEs ---- Feb we \ oS ne eee eee Mar TAS aA Dis Se : ae Se 2 SES Des ps SScoes 1 = > 0) 4 3 2 1 0) 4 3 2 1 0) =D —1 ) 1 10 10 10 10 Percent Greater Than Indicated Figure B4. 1980-1988 monthly wave height distributions for Gage 630 B17 Frequency of Occurance, % 40 Gage 630 1988 Gage 630 1980-88 ae Zale YY Balt 6 gage __ bone ie Gage 625 1988 Gage 625 1980-88 - Zig aval j_ofadlAhoo_]__.ntaladen a Gage 111 1988 Gage 111 1985-88 of -naltalQe Ae { _ oolong _ ole Gage 645 1980-88 20 s An rr Wt DAs 4 56) 7 Ol OelOm125 145.16 2 Sus 5) 6) 7) 8 Sl ORI 2Z al 4 aa 6 Period, sec Period, sec Figure B5. Annual wave period distributions for all gages B18 Frequency of Occurrence, % J an Jul y Pied me 1 alr ‘alee Nanna tee. 1 | L (|e | Feb 20 . fee Neo j | ofa wo@d..|_ Babe 405 = Mar 2074 Jaded __ Sep y _ A0bed 0 1 20 Mp | j ; : _antandden. See eda 7 my ; yonlta1_.oPatoo-—. 910 12 14 16 Figure B6. 1988 monthly wave period distributions for Gage 630 Frequency of Occurrence, % 40 0 405 207 S| O- 407 ral ‘ < 20-7 0 407 | 204 J 0-! 407 4 Jan 4 aeons | Feb Ses lean a __ Abend! Mar et _ Goods. | Jul Ap edhe Ap __ AACA oe __ Ween May ie age 7) __ need en) Oia em Oe One Oana LL ie 23 4 eS ee Geet 7S CA aay a ae he ath ales 10 9 8 503325 Feel Sr) Ole ee One an vs mae. SON le One Avene 2: 1 Cul: aie sy 872 6G 2 Sel B21 7 Sa 4, 1 5 1 19+ 3 RELATIVE ENERGY DENSITY RELATIVE ENERGY DENSITY Figure B8. L4SLZ/ LYS Le L259 S> Sos SLL PSS TSI rar Sos ra 1988 monthly spectra for Gage 630 (Sheet 1 of 6) B22 RELATIVE ENERGY DENSITY Gaitaeo eot>NRak Of ON Ae OO Nt Co! te RELATIVE ENERGY DENSITY 0.05 Figure B8. 0.25 » Hz I) ee [Wipes (Sheet 2 of 6) B23 S22>> a | I) KD LIE SSS }? S2IEKES Sesessse Li {\ 1 NRE LOL LIFTS = SoSSze RELATIVE ENERGY DENSITY RELATIVE ENERGY DENSITY | Peescoooerees =e 1) ELL TS ALL) 973 " My) = Ke ayy) LN PA Figure B8. LPR ESS ISS ISS SSO TLL TT EEE [] OSES L? Ie = LODE KLIS, SSS SOS SLOSS Sees S2 Sco SS SESS oS LISS POSES (Sheet 3 of 6) B24 NSITY ELATIVE ENERGY DE R NSITY ELATIVE ENERGY DE. R Se ZL7 ZL 1 SSS SESS SSS —- LoZ> OM A Soa Pig SS SSSZZ7 Ih Sm] ie SS5 Ze |__| SSS OSS SS NESS SSE Sesse Sey, VRS Roose Par serene S2SSS255 Sess es SES o ees oo ‘6 IS SSE ESS EA SoSees SSSSSS ISLC —— eeawag ee = LEE IIA IEG SESSEES S255 SSS PLeSSe 27H SZ Sse Sees ose Eieure sBee a, ral (Sheet 4 of 6) B25 RELATIVE ENERGY DENSITY RELATIVE ENERGY DENSITY 4 oe p77 ZA SQ ae $5522 0. FREQUE 0.25 SESS eOS Ee Ney, Hz 0.39 <25 1 Figure B8. S2 LESS 2S LOSS S22 <2e5 (Sheet 5 of 6) B26 SESS 2osS2 aa “i LTT FOSS o OS 13 oath eeeceesLeT7psce | 10 oct RELATIVE ENERGY DENSITY RELATIVE ENERGY DENSITY \) hy \) ws es ee i TN, _\ RAN SY wy uy =@ AK) AK} ay Figure B8. aeeaiyhs, zi a Ye IT, ———— | y= A | cS ———$—$——— Sine > < mm ro) > a m a Ww oO 1988 eee eh ose (We SY ire ee COISKLIF TSS IS LLIT Fo OS ELLE SPSS LOTS (Sheet 6 of 6) B27 Annual Mean 1988 1980-1988 Period Height Period Std. Std. Std. Mean Dev. Number Mean Dev. Extreme Mean Dev. Bl opel De Date iseciy Seci L0bS.u7 pms Ame ane Date, esecs (sect 8 8.5. 3.1 124 74 AW G7/ 4.5 1983 8.0 2.8 28 728 256 116 12; 1 0)57: 5.1 1987 8.5 2.6 11 738) Lieve 121 Moa {e7/ 4.7 1983 8.6 2.7 13 839) 5 351 116 1.1 0.7 5.2 1988 8.7 2.8 7 8.6 1.6 111 0.9 0.5 6s) 1986 8.1 2.3 4 8.0 2.0 101 0.8 0.4 2.4 eh ath ee 1 U0 Na7/ 121 (a7) WSS) Qed 9855 Set 2.5: 31 Tic eel 119 0.8 O.5 3.6 1981 7.9 2.4 8 Uy iPod 111 1.0 0.6 6.1 Ee 6a. 7263 8 CER ZA57/ 108 127 1037. 4.3 1982 8.7 2.8 24 iste}, oul 94 Meer O07, 4.1 1981 759" 52.8 4 TG) 132. 118 Bay Waz7/ 5.6 1980 8.3 3.0 Apr 8.0 2.6 1360 1.0 0.6 6.1 Sep 1985 8.3 2.6 ee Oo PRPRPRPOCDOORPRPRPHEH Gn Oech, On On On Ome O CRPOOCOON@MOWOrFN Height Std. Dev. oooooococoeoe°coeo°coe OF OF DE DLs Oe Of the On On Led AaInIwgwnwnorhaa Oo e oa Extreme uo ° N NNNNRPRPNN UND W ah i Lobes. Gait sO On On DPOROArPEPNNNNE Table B/7 Wave Statistics for Gage 630 B28 Height, m ON F ON FON FON FP ONH FON fF Period, sec W935) 7 91 11 15:18:47 1921123 25.27 29): 1/3515: 79 11 13115 17 19. 21.25.25 27 29 31 Day of the Month 20 Jan Jul 10 i) 20 Feb Aug 0 20 POR tecnica 10 0 20 10 0 20 10 av mel 0 20 10 0 1.3 5 7 $111 13 15 17/19 212312527 29) 1 3°57 9 1113 15 17 19 2123.25 27 29151 Day of the Month Figure B9. Time-histories of wave height and period for Gage 630 B29 re. core . tees : ft @ ity ct . é ; a . me Moet tie ved jie atl DAT MRP RE : ; A nes eee eT a | met i ‘pal ee ey ‘y" tw if | ” — tae fi) ; 4 hie" Tt = is ’ Y or. & es Bess Ge ert} a t be on Maes ETS ye i dinoM ant.)6 Yaa: Mer Lene aya winewe x i . : v } te . . -¢ @ 4 rar |