July 11th 08, 10:57 AM
posted to rec.aviation.soaring
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Developing A "Hot Spot" Map
An entirely different but interesting approach:
Quote:
After this lecture Beda Sigrist, also from Switzerland presented his
paper “Use of topographic radar scans to identify thermal hotspots in
Alpine areas”.Thermals are part of the atmospheric energy flow caused
by solar irradiation. The question behind this project, called
TherMap, has been if variations of the solar irradiance, caused by the
local topography, could be a useful predictor of thermals. Using high
resolution digital data of the topography the local irradiance was
therefore computed. The results, considering the different radiation
angles were displayed on maps, leading to first plausible results for
the morning hours of mountain areas. In a second step these models
were refined to consider the thermal inertia of the soil and the air,
the different vegetation factors, as well as the reflection of snow
surfaces. For Alpine areas the resulting maps turned out to show a
high level of agreement with superimposed flight tracks. For
topographically less significant areas, like the Jura, the results
were not so good. No conclusive results could be obtained for
topologically still smoother landscapes, where other factors are
likely to be predominant.
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from
http://www.wgc2006.se/sub/firstpage.php?Id=67
Dan
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