[cam-users] What is pcols?

[Ghan, Steven J]

Eddy:

pcols is the number of columns in each physics chunk. The physics
calculations are distributed into chunks to facilitate load balancing
and to improve the use of cache. The value of pcols has been found to
optimize performance on some machines, but it can be changed if desired.


CAM2 provides functions to map between chunk indices and lat/lon
indices. See get_lon_p and get_lat_p in phys_grid.F90. 

-Steve Ghan

-----Original Message-----
From: Chul Eddy Chung [mailto:cchung@fiji.ucsd.edu] 
Sent: Monday, June 30, 2003 2:17 PM
To: cam-users@ucar.edu
Subject: [cam-users] What is pcols?


I am running CAM2 at T42/L26.  I am trying to modify the solar radiation

code in order to put spatially-heterogenious absorbing aerosol effects. 
I have a hard time understanding how the CAM2.0 treats the latitude and 
longitude indices.  In CCM3, the solar radiation code calculated all the

levels and longitudes at a given latitude.  Seems like the CAM2 solar 
radiation code only calculates all the levels at a given latitude and 
given longitude.

I have specific questions.  What is pcols (PCOLS)?  The value is 16 in 
case of T42/L26 CAM2, and according to 'ppgrid.F90', pcols is number of 
columns (max).  What is the column as opposed to layer?

-- 
Chul Eddy Chung: Assistant Project Scientist
Scripps Institution of Oceanography, UCSD
Tel: 858-822-1356   Fax: 858-534-7452


_______________________________________________
cam-users mailing list
cam-users@ucar.edu http://mailman.ucar.edu/mailman/listinfo/cam-users