Rice fields in Bali, photo: edie209 via flickr
You only have to have had a cursory introduction to possible effects of global warming to have heard that rising temperatures are going to effect both water supply and crop yields. A new report indicates that by 2100 up to half of the world's population could face food shortages, if we don't actively work to adapt to rising temperatures. This is what the University of Washington's David Battisti's research discovered:Crop Yields Could Be Cut 20-40% by 2100
Because of global rising temperatures crop yields in both mid and equatorial latitudes will be hindered. In the tropics higher minimum temperatures are likely to cut crop yields of maize and rice by 20-40% (not even taking into account the effect of temperatures on decreased soil moisture...). In higher latitudes, Battisti cited the heat waves in France in the summer of 2003 which cut wheat yields by 33% saying that by 2100 those sort of temperatures could be commonplace.
Battisti summed up the situation we could be facing with active adaptation:
I think what startled me the most is that when we looked at our historic examples there were ways to address the problem within a given year. People could always turn somewhere else to find food, but in the future there's not going to be any place to turn unless we rethink our food supplies.
... You are talking about hundreds of millions of additional people looking for food because they won't be able to find it where they find it now.
More on Battisti's research: Science Codex
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