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Changes in wind direction over land and sea

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User 4586
(@user4586)
Trusted Member Customer
Joined: 10 months ago
Posts: 29
Topic starter  

Hi Bob/Stuart,

My understanding (as per BT textbook) was that friction over land is more and the surface wind speed drops by two-thirds over land and veers by 30 degrees.
However, in a Bureau of Meteorology online course it was said that wind speed over sea drops by two-thirds. Could you please let me know which one is correct.
Attached is a picture of both.

Cheers,
Raji



   
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Bob Tait
(@bobtait)
Illustrious Member Customer
Joined: 17 years ago
Posts: 2538
 

Hello Raji
I think you will find that the Bureau of Met book says that the wind speed over the sea is reduced [i][b]TO[/b][/i] two thirds of the gradient wind. In my book I said it is reduced [i][b]BY[/b][/i] one third. Both are saying the same thing.

Bob



   
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