m. BASIC ENVIRONMENTAL MEASUREMENTS 



A variety of oceanographic and meteorological instruments have been 

 installed at the FRF in support of a basic environmental measurements program 

 established in late 1977 to collect data on local conditions. The program 

 consists of daily measurements of wave, current, water level, water tempera- 

 ture and salinity, wind and weather conditions, quarterly aerial photographic 

 missions, and periodic beach and bathymetric surveys. In addition, daily 

 photos and visual observations and weekly bottom surveys along the pier are 

 collected. The data are available to anyone interested and may be obtained by 

 writing to: 



U.S. Army Coastal Engineering Research Center 



Technical Information Division 



Coastal Engineering Information and Analysis Center (CERTI-CE) 



Kingman Building 



Fort Belvoir, VA 22060 



The requestor will be responsible for reproduction and mailing costs; requests 

 should be specific. Questions may be directed to the Technical Information 

 Division by telephoning (202) 325-7386. Monthly data reports, starting with 

 October 1980, are available the month following collection. Annual reports 

 summarizing a year of data collection will also be prepared. Near real-time 

 data summaries will be available to researchers working at the FRF. Miller 

 (1980) describes the instrumentation at the FRF. 



1. Instrumentation. 



Table 3 summarizes the instrument installations presently included in the 

 measurement program; locations are shown in Figure 9. Of particular interest 

 is the X-band radar used to obtain wave directions. The radar unit is located 

 on the laboratory roof. Details of the system are reported by Mattie and 

 Harris (1979). 



Not included in Table 3 is an Sxy gage installed by Scripps Institute of 

 Oceanography in September 1980. It consists of a four pressure-gage array 

 capable of measuring near real-time directional wave spectra. The data and 

 analysis are available interactively via a computer terminal and in monthly 

 data reports. 



The visual observation program consists of data collected daily at the 

 pier end, pier nearshore, and on the beach. These observations suppleiaent the 

 instrument records by providing information on the type of breaker, direction 

 of wave approach, width of the surf zone, littoral currents, beach slope, the 

 presence of rip currents, water quality, and prevailing weather conditions. 



Lead-line surveys are made weekly along both the north and south sides of 

 the pier, using a graduated surveying tape with a 5-pound weight attached. 

 The same positions along the pier are measured midway between the pier bents, 

 to minimize the effect of the scour around the pilings. Periodic surveys to a 

 depth of 9 meters are also made of profile lines located approximately 500 

 meters north and south of the pier. 



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