Accession Number : AD0714888

Title :   Fourier Analysis of Weather and Wave Data from Lake Michigan.

Descriptive Note : Technical rept.,

Corporate Author : WILLIAMS COLL WILLIAMSTOWN MASS

Personal Author(s) : Fox,William T. ; Davis,Richard A. , Jr

Report Date : 20 OCT 1970

Pagination or Media Count : 51

Abstract : Field data were collected on wave and weather parameters at Stevensville and Holland, Michigan during the summers of 1969 and 1970. Weather parameters include barometric pressure, wind speed and direction, air temperature and sky condition. On-shore and along-shore components of the wind were derived by a sine transformation of wind direction. Lake and groundwater levels were recorded from pipes placed in the beach. Wave parameters including period, height, depth, breaker angle and breaker distance were recorded at the plunge zone, in the breaker zone, and at a tower located 585 feet offshore. Measurements of the parameters were made at two hour intervals for thirty days for a total of 360 observations per variable. The observed data was analyzed on the computer by extracting the first 15 Fourier harmonics for each variable, computing the percentage of the total sum of squares accounted for by the harmonic and plotting the resultant curve. The curves are strongly influenced by a low pressure system which passed through the area on 27 and 28 July 1969. The curves for barometric pressure, wind speed and direction can be correlated with those for breaker height, breaker angle and longshore current. The curves for breaker angle and longshore current velocity closely resemble the first derivative of the curve for barometric pressure. (Author)

Descriptors :   (*WEATHER FORECASTING, FOURIER ANALYSIS), (*GREAT LAKES, *LAKE WAVES), WIND, TIME SERIES ANALYSIS, BAROMETRIC PRESSURE, MODELS(SIMULATIONS), DATA PROCESSING, TABLES(DATA)

Subject Categories : Meteorology
      Hydrology, Limnology and Potamology

Distribution Statement : APPROVED FOR PUBLIC RELEASE