reference; (d) the starting and ending chart times were recorded, as neces- 

 sary; and (e) new charts were installed when needed. 

 Analysis 



37. Air temperature. Mean air temperature was computed four times per 

 day from 20-min digital data samples. From these data, monthly and annual 

 means were determined. 



38. Monthly and annual mean and extreme highest and lowest daily tem- 

 peratures were determined from the daily maximum and minimum thermometer 

 values. 



39. Atmospheric pressure. Mean atmospheric pressure was computed four 

 times per day from 20-min digital data samples. From these data, monthly and 

 annual means were determined. 



40. Wind speed and direction. Mean wind speed and direction were com- 

 puted four times per day from 20-min digital data samples. 



41. Annual, seasonal, and monthly joint probability distributions of 

 wind speed versus direction were computed. Wind speeds were resolved into 

 3-m/sec intervals while 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 

 occurrence of wind blowing from the specified direction and the width of the 

 petal is indicative of the speed in 3-m/sec intervals. Resultant directions 

 and speeds were also determined by vector-averaging the data. 



Wave Data 



42. Thompson (1977) and Harris (1974) describe the procedure used for 

 analyzing and summarizing the digital wave data contained in this report. The 

 procedure is based on a Fast Fourier Transform (FFT) spectral analysis of 

 4,096 data values (1,024 sec sampled at 4 Hz) for each file processed. 



43. The program computes the first five moments of the distribution of 

 sea-surface elevations, then edits the digital data file by checking for 

 "jumps" and "spikes" and for data points out of the 0- to 5-V range. A jump 

 is defined as a data value greater than 2.5 standard deviations from the 

 previous data value, while a spike is a data value 5 standard deviations or 

 more from the mean. If less than 5 jumps or spikes in a row are found, the 

 program linearly interpolates between acceptable data values and replaces the 



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