how to mask the data

["Yogesh K. Tiwari" <ktiwari@xxxxxxxxxxxxxxx>]

Hello ferret Users,

I have CO2 data from satellite which covers from 
Jan03 to Dec03.

I want to see the CO2 variation separatly at land 
and at ocean.

I want to make shade plot, the zonal mean monthly 
variations of CO2 (x-axis as months from jan to 
dec and y-axis as latitude).

How I can mask the land data so I can look only 
the monthly variation over the ocean and vice versa.

Is there any way to do this.

Many thanks for your help,

Regards,
Yogesh
--

===========================================
Yogesh K. Tiwari,
Max-Planck Institute for Biogeochemistry,
Beutenberg Campus, Hans-Knoell-Strasse 10,
D-07745 Jena,
Germany

Office   : 0049 3641 576 376
Home     : 0049 3641 223 163
Fax      : 0049 3641 577 300
Cell     : 0049 1520 4591 008
e-mail   : yogesh.tiwari@bgc-jena.mpg.de
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