Find the LCL / 'define' problem

[Douglas Clark]

Marco,

You can probably do what you want using 'set defval'. This can be used
to set the value of a 2-D variable at a single point. As it says on
http://grads.iges.org/grads/gadoc/gadocindex.html:

"set defval var ival jval value
where:

var    - the 2-D defined variable
ival   - X coordinate of the grid point
jval   - Y coordinate of the grid point
value  - the new value for the variable"

So you could calculate the LCL at each (x,y) point and then set the
value of the gridded lat/lon variable.
I've got a feeling that 'set defval' can only change the value at t=1,
which might limit its use for you, but maybe I'm wrong....

Hope this helps,
Doug

>>> stoll at GIUB.UNIBE.CH 09/05/2005 13:27:57 >>>
Dear GrADS users,

I try to calculate LCL in my gridded data set (terrain following model
layers).

My algorithm steps upward from the surface iteratively always one
level, calculates the thetaE at this level and compares
with the mixing ratio in order to check, wether LCL is reached or not.

This works fine for one single gridpoint, but how can I find
the LCL's over the whole domain? Since, it is reached at
different vertical levels, I cannot just do the calculation
with the whole array.....

Is there a way to go through every gridpoint and define
a single variable 'lcl' dependent on lat/lon?

Thanks in advance for your help and proposals,

Marco


===========================================
Marco Stoll, Student of Geography
Zaelglistrasse 18
3202 Frauenkappelen, Switzerland

Institute of Geography, Universtity of Bern
Climatology/Meteorology Group

email: stoll at giub.unibe.ch
Phone: 0041 31 920 03 53
Mobile: 0041 78 759 83 29
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