Dear All,

I am using DSSATv4.5 for simulating the wheat yield
over different sites in Northern India.  Here during the months of
December and January, there will be no sunshine (Sunshine hours= 0)
hours.  But while estimating the solar radiation from sunshine hours
during no sunshine hours days will be minimum of 5.4 to 6.0 based on the
 solar angle and latitude (and the constants a and b).   The actual
radiation will be more than this.  This means we are using low solar
radiation values and most of the simulations, the biomass production
will be far below the actual.  But the grain yield will be comparable. 

My
 point is whether any other methodology to estimate solar radiation
under these circumstances. ie from temperature. Please suggest.

Thanks to all.

With regards
Subash


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Dr. N. Subash (ARS)

Senior Scientist (Agricultural Meteorology)

Division of Cropping System & Resource Management (CSRM),

& i/c ARIS, Remote Sensing & GIS

Project Directorate for Farming Systems Research

(Indian Council of Agricultural Research)

Modipuram, Meerut-250 110. Uttar Pradesh, India

Cell No -  +91-9457248070

Email: [log in to unmask], [log in to unmask]

[log in to unmask]

www.pdfsr.ernet.in

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