Re: Extracting monthly means and anomalies

[hankin@xxxxxxxxxxxxxxxxxxx (Steve Hankin)]

Hi Steve,

My apologies on the delay answering this -- I have been away on travel.

Mark Verschell (Nov. 1) offered you a workable solution (thanks, Mark!) but
I'd like to note that version 4.2 of Ferret has simpler and more general
capabilities for handling climatological calculations. They are written
up in the release notes at:

  http://www.pmel.noaa.gov/ferret/release_notes/release_notes_v420.html#v42_clim_regridding


	Happy Ferreting - steve

======================================================================

On Nov 1, 11:58am, WILSON Steve wrote:
> Subject: Extracting monthly means and anomalies
> 
> I have a gisst.nc file with array "sst" monthly from 1871 - 1991.  It's a
> 4D file:  longitudes(i), latitudes(j), level(k=1), year(l) so it already
> has a time axis with values like 1950 , 1950.083 , (for jan, feb 1950) to
> 1991.833 , 1991.916 , 1992.  
> 
> I would like to extract (and later use for plotting):
> 
> (a) a mean climatology, say sstm (containing 12 monthly mean values) to
> gisst_m.nc, over say years 1950-1991.  This means averaging every 12th
> value from the gisst.nc file.
> 
> (b) monthly anomalies: i.e., using both "sst" from gisst.nc and "sstm" 
> from gisst_m.nc, to calculate monthly anomalies over the same period
> 1950-1991 and write them out, say to "ssta" in a file gisst_a.nc.
> 
> Can you suggest a way to do this?
> 
> 
> =====================================================================
> ***** Steve WILSON
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> 
>-- End of excerpt from WILSON Steve



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