ADDITIONAL WAVE STATISTICS FCR STATIONS ON LAKE MICHIGAN AND LAKE ERIE 



by 



Charles E. Lee, Civil Engineer 

 U. S. Army Engineer Division, New England 



In 1953 for use in the survey report on Great Lakes Levels, the 

 Great Lakes Division of the Corps of Engineers (now U. S. Amy Engineer 

 Division, North Central) obtained from the United States Weather Bureau, 

 Department of Commerce, a five-year period of recorded hourly obser- 

 vations of winds taken at first order weather stations along the perimeter 

 of the Great Lakes. Also, for use in the before-mentioned report, wave 

 hindcasts were made for the 5-year period 1948-1952 by engineers in the 

 Chicago, Buffalo and Milwaukee Districts and by the writer. Fetches 

 used are shore-to-shore straight line distances in the direction of the 

 wind as determined at the shore station. A further analysis of the 

 results obtained from the hindcasts made in 1953 is presented herein. 

 The basic data and original sheets of the hindcasts are in the files of 

 the Division Engineer, U. S. Array Engineer Division, North Central. 



For each storm occurrence, as indicated by the wind records, the 

 highest wave over 4 feet occurring during the storm was determined auid 

 tabulated as one occurrence of that specific height. The hindcasts are 

 for deep water waves, not affected by refraction or shoaling, and were 

 obtained by use of curves derived by Sverdrup and Munk (1)* and revised 

 by Arthur (2) and Bretschneider (3). The hindcast procedure is described 

 in paragraphs 1.232 and 1.233 of Beach Erosion Board Technical Report 

 Number 4 (4). Data on wave periods and wave duration are not available 

 for use in this paper; therefore the statistics presented are in effect 

 occurrence of storm winds of sufficient strength to cause the formation 

 of waves of the stated height. The number of occurrences per year are 

 average values derived from the expression F = N/T , where F is the number 

 of occurrences per year, N is the total number of occurrences, and T is 

 the period of record in years. The stations considered are Muskegon, 

 Michigan and Milwaukee, Wisconsin on Lake Michigan; and Buffalo, New York 

 and Cleveland, Ohio on Lake Erie. The locations of the sites are shown 

 on Figures 1 and 2. 



Figures 3-6 each contain two curves which are plots of the average 

 number of times per year that waves of various increments of height were 

 predicted to occur during the ice-free portion of the year and during 

 the full year. The ice-free year is considered to be that portion of 

 the year between 1 April and 31 December. Also shown on Figures 3-6 

 are plotted frequency data (solid symbols cind dashed curves) from the 

 hindcast statistics for the 3-year period 1948-1950 presented by Saville 

 (5, 6). Differences between the frequency of occurrence of specific 



* Nombers in parentheses refer to Bibliography at end of text. 



