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Old 3rd March 2008 | 19:28
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Nipper2
 
Joined: Oct 2006
Posts: 201
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From: Fareham
Gusts tend to veer (increase in bearing or more to the right) in the northern hemisphere. They go the other way in the southern hemisphere. The closer you get to the equator, the less noticeable the effect.

This is something we have looked at a lot in sailing and there are a huge number of factors that influence the gust velocity. Surface roughness, stability (vertical airflow) and vertical wind-sheer are the key ones.

Perhaps surprisingly, very little research has been done into wind flow at ultra-low altitudes (less than 5m) except in cities where a good body of information exists. The standard measuring height for wind (10m) did not come about by accident....

Also bear in mind that gusts are a three-dimensional phenomenon. It's easy to think of wind as always blowing parallel to the surface of the earth and only changing direction in terms of compass bearing. In reality, most gusts will also include an increased downwards component of air movement.

Last edited by Nipper2; 4th March 2008 at 08:16.
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