20001010: Gempak, vector diagnostic function

>From: Luis Farfan <address@hidden>
>Organization: UCAR/Unidata
>Keywords: 200010101945.e9AJj3405691

>
>I am looking for a function that allows me to compute the average of a
>vector within a vertical layer. For example, the mean winds in the 850-300
>mb layer.
>
>According to the gempak user's guide, the fuction VLAV allows the
>computation of a vector in a layer defined by 2 levels. Could you please
>provide a brief explanation of what is the format of the input fields?
>
>Also, are there other functions that I could use to compute the avarage of
>a layer that contains more than 2 levels?
>
>Thank you, Luis M Farfan.
>

Luis,

for layer average functions such as VLAV, specify the 2 levels
in GLEVEL, such as GLEVEL=300:850, then GFUNC=VLAV(OBS) will
use the 2 levels.

Unfortunately, there is no function to compute a mean within multiple
levels when defining a layer (eg, using all levels from 850 to 300MB
including 800, 750, 700, 650 etc...). 

Steve Chiswell