Dear Dharam,

Temperature amplitude in DSSAT is simply 1/2 of the long-term mean
temperature ((mean TMax + mean TMin) / 2) of the warmest month minus the
mean temperature of the coldest month.  The soil temperature submodel
model uses it.  The DSSAT WeatherMan program calculates it automatically
whenever it imports daily weather data.

Dharam Dabas wrote:

> Dear friends,
>
> Thank to Dr Murthy for his response. I wish to restate my question to
> you all so that I get the appropriate reply.
>
> The quantity <Temperature Amplitude> is a Station Data. So it must be
> an attribute of the station. The quantity must be the mean of several
> years for that station.
>
> There can be several temperature amplitudes of the type Dr Murthy has
> defined, diurnal, weekly, monthly or annual swing in the temperture
> values over the period.
>
> My question was which of above quantity is to be used and how to obtain
> or calculate the same.
>
> Dharam Singh Dabas
> CCS Haryana Agricultural University,
> Hisar 125004 India
>

Regards,
--
Dr. James W. Hansen
Associate Research Scientist - Agricultural Systems
International Research Institute for Climate Prediction
The Earth Institute at Columbia University
121 Monell Bldg., Lamont-Doherty Earth Observatory
PO Box 1000 / 61 Route 9W
Palisades, NY 10964-8000
USA

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