Hi Munang,
You have triggered a nice exchange on modeling effects of climate change.
If somebody wants to go into further detail, they should consider posting
their remarks on the ICASA Open Forum (http://168.29.150.63/icasaforum/).
You don't need to join ICASA or even join the bulletin board.
Figuring out what climate scenario to consider is only a first step. Other
activities to keep in mind include:
- Assessing the model's suitability for modeling temperature response. Do
you have access to data from planting dates studies, altitudinal
gradients, etc. that would allow you to test the model? Alternately, you
should conduct sensitivity analyses.
- CO2 response -- Research suggests that increasing CO2 shifts temperature
optima for photosynthesis upwards (greater heat tolerance). Increased CO2
certainly can increase crop water use efficiency.
- Precipitation effects -- I am not a climatologist, but one gets the
impression that effects of climate change on precipitation patterns could
override temperature effects. Unfortunately, predictions of changes in
precipitation seem to vary greatly with the climate models.
- Adaptive response of growers through cultivar or crop choice -- The
largest effects of high temperature usually is to accelerate development,
hastening maturity and reducing net productivity and economic yield.
However, growers can compensate for earlier maturation by growing later
maturing cultivars or even changing crops. In Canada, there are reports
that areas that used to grow only rye and barley are producing wheat,
which is less cold tolerant.
- Adaptive response of growers through crop management -- Again, farmers
will change planting dates, rotation sequences, fertilizer regimes,
irrigation practices, etc. as the environment changes.
Thus, it is not very informative to run a crop simulation model for a few
climate change scenarios. You really need to think about possible changes
in the entire prodction system.
Best regards,
Jeff
Jeffrey W. White
USWCL, USDA-ARS
4331 E Broadway Rd
Phoenix, AZ 85040
Tel. 1-602-437-1702 x 268
Fax 1-602-437-5291
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Munang Tingem <[log in to unmask]>
Sent by: DSSAT - Crop Models and Applications <[log in to unmask]>
12/21/2005 03:16 AM
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DSSAT - Crop Models and Applications <[log in to unmask]>
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Subject
Climate Scenarios
Dear all,
I am simulating the effects of climate chnage on crops in Central
African region.I wish to use climate scenarios.Please do any one know the
best climate scenraios that can be used for thsi study.Kindly help
Merry X-mas and a happy New year.
Munang
Munang R.Tingem
17 Austrey Avenue
Lenton abbey
Notttingham
NG9 2SX
United Kingdom.
UK Mobile: +44(0)7910377001
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