During a private course yesterday we spent some time looking at the effect of the wind on trees and grass. We also looked at the lee effect, when leaves and other natural drifting materials accumulate on the lee side of obstacles.
This is something that I am both more sensitive to and wary of since my trip to the Sahara in March. The lee effect there puzzled me for several days until a sandstorm blew in and blotted out the sky. Ironically it clarified things mentally. There is a difference between a prevailing wind and wind that has a huge short-term impact. The sand that was deposited in some areas that I crossed in Libya indicated a wind direction that clashed with the direction that both the trees and the dunes were suggesting. It became clear that this was caused by a sandstorm blowing in from a different direction to…
