Beyond Pesticides, March 19, 2007) Stanford University and Lawrence Livermore National Laboratory researchers are publishing a study saying that some of the world’s farms are yielding markedly fewer crops because of global warming, according to theSan Jose Mercury News. Meanwhile, providing further evidence that the pace of global warming is accelerating, scientists announced last week that this winter was the hottest on record - and that surface temperatures around the world have been increasing at three times the rate they were before 1976.
This warming most likely is costing the planet $5 billion annually in losses to three of the six major food crops, the Stanford and Lawrence Livermore researchers say. The study warns that wheat, corn and barley are especially affected, with 40 million fewer metric tons of the crops produced each year. For every 1 degree increase in temperature, the researchers say, crop yields drop by about 3 percent to 5 percent, and the decline is clearly caused by human activity.
“Global warming is having real impacts - and we’re seeing their effects already,” said Chris Field, one of the authors of the crop study, and director of the department of global ecology at Stanford’s Carnegie Institution.
“This is a sign we’re going to have more of this [crop loss] in the future,” said Kevin Trenberth, head of the climate analysis section at the National Center for Atmospheric Research in Boulder, Colorado. “This will have an impact on many things that will affect humans, from food and crops but also on all kinds of ecosystems, wildlife, forests, even fisheries and especially things like wildfires, things that can be really devastating.”