Friday, January 9, 2009

Will rising temperatures trigger food shortages by 2090?

The results of a recent study by David Battisti (University of Washington) and Rosamond Naylor (Stanford University) analyzing data from 23 global climate models has revealed a 90% chance that most of the tropic and sub-tropic regions of our plane will experience "unprecedented seasonal average temperatures by the end of the twenty-first century." This alone, of course, is hardly surprising news. Here's the other part. On top of studying those 23 global climate models, which were produced for the Intergovernmental Panel on Climate Change, they examined case studies of three areas that have experienced extreme heat waves and the resulting impact temperatures had on food production. From the Nature article:

"France felt some of the greatest impacts of the 2003 heat wave in Western Europe, seeing mean temperatures rise to 33 °C between June and August — nearly 4 °C higher than the country's average historical temperature for those months. Over this period, production of maize (corn) fell by 30%, fruit harvests declined by 25% and wheat harvests dropped by 21% compared with the year before. The study, published in Science, claims that by the end of the century, the temperatures experienced in the summer of 2003 will be the norm for the season in France."

Critics have pointed out these agricultural shortages could (or should) be attributed to drought, as opposed to extreme heat, and that with sufficient rainfall or irrigation, crop yields could potentially increase in other regions. Of course you then have to ask what causes droughts and so on and so forth...

I recommend reading David Biello's recent article on the topic in Scientific American, that acknowledges climate change, a greater demand for food, biofuels, and so forth as causes leading to an agricultural breaking point, not just record-breaking heat. Find it (and more info about the doomsday temperature increase maps posted below) here.

Alaska, anyone?