Dear Rolf,

Peter Jones at CIAT developed a program called MarkSim, which does just
exactly what you want. You input the monthly data (called climate normal
data) and MarkSim will generate as many years' data as you want (in sets of
99 years, if you want/need more you put in different random number seeds.)

You can also use MarkSim's built in climate surface to generate data for any
place in the tropics with a resolution of 10 arcminutes (~18km at the
Equator). This is a bit coarse for variable terrain, so you can extract the
climate normal data from WorldClim with a resolution of 30 arcseconds (~1 km
at the Equator). WorldClim is a much bigger database of course and hence
needs more bandwidth to download it.

The program is available from CIAT www.ciat.cgiar.org.

Cheers.

Myles Fisher
----- Original Message -----
From: "Sommer, Rolf (ICARDA)" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, July 17, 2008 1:24 AM
Subject: disaggregate monthly rainfall data


Dear all,



I have historic rainfall data (1940-1985) as monthly sums, which I would
like to disaggregate to obtain approximate daily data to use it for crop
modeling. I wonder if anybody of you ever has done this, if there is
standard procedure or (even better) software that could do that for me.



Of course, I have more recent (approximately 30 years) daily records of
the same region. So I could do all kind of supporting statistical
analyses.



Best regards,

Rolf





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Dr. Rolf Sommer

Agro-Ecosystem Modeling

International Center for Agricultural Research

in the Dry Areas (ICARDA)

P.O. Box 5466, Aleppo, Syria

Tel 00963 21 2691 590

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