where H is the deepwater significant wave height in meters or feet (derived 

 from empirical data showing that the wave steepness H/gT will be about 

 0.0068). 



*************** EXAMPLE PROBLEM 8*************** 



GIVEN ; A hurricane at latitude 35° N. with R = 67 kilometers, Ap = 

 760 - 701 = 59 millimeters of mercury , and forward speed V^ = 14 

 meters per second. Assume for simplicity that a= 1.0 . 



FIND: The deepwater significant wave height and period. 



SOLUTION: 



Using equation (3-63) 



U = 0.447 [14.5 fp - P^}^ - R (0.31f)] 

 max '- n o' 



max 



= 0.447 [l4.5 (59)^^^ - 67 (0.31 x 0.300)] 



U = 0.447 (111.38 - 6.23) = 47.0 m/s 

 max, 



Using equation (3-62) 



U„ = 0.865 U + 0.5 V„ 



R max F 



U_= 0.865 (47.0) + 0.5 (14) = 47.66 m/s 



R 



Using equation (3-59a) 



H = 5.03 e 

 o 



RAp 



4700 



0.29 a V 



1 + 



where the exponent is given by 



M2_ = 67(59) ^ 



4700 4700 "-^^^ 



then 



H = 5.03 [e^-S^lj 

 o 



1 + 



0.29 X 1 X 14 



■\/47.66 



<^ 



H = 5.03 (2.32) (1.588) = 18.5 m 

 o 



Using equation (3-60a) 



T = 8.6 e 



s 



RAp 

 9400 



0.145 a V 



1 + 



Vu 



R 



where the exponent is given by 

 RAP _ 67(59) 



9400 



9400 



= 0.421 



3-86 



