※ 本文轉錄自 [Meto_e] 看板
發信人: Icebound <ice.bound@rogers.com>, 看板: Meto_e
標 題: Re: Why is 850MB so important?
發信站: (Fri Dec 20 19:34:02 2002)
轉信站: itcz!news2.wam.umd.edu!cadig2.usna.navy.mil!hammer.uoregon.edu!arclight
Origin: 24.100.76.111
Daryl wrote:
> ... snip ... What happens at 850 MB that does not happen at
> 700MB ... [snip]?
> ...
What "happens" at each level is quite different and any *one* level can
be an indicator which becomes part of the overall puzzle.
As James pointed out, 850 is a mandatory level that is probably pretty
close to the mid- or upper- levels of most lake-effect cloud, and is
very useful in determining the extent of the moisture at those levels.
Also, the wind patterns at this level can help identify areas of
convergence at low levels (which in turn imply ascent, a usual
contributor to convection). This level can also be useful in
identifying frontal zones, especially those that may be masked by
nighttime temperature at the surface, or by other surface effects.