"One of the limitations of previous forecasts is that they don't consider the full range of uncertainties that is, the chance that things could be better or worse than we expect," Lobell said. "We provided Tom those three scenarios of what climate change could mean for agricultural productivity. Then he used the trade model to project how each scenario would affect prices and poverty over the next 20 years.
"The impacts we're talking about are mainly driven by warmer temperatures, which dry up the soil, speed up crop development and shut down biological processes, like photosynthesis, that plants rely on," he added. "Plants in general don't like it hotter, and in many climate forecasts, the temperatures projected for 2030 would be outside the range that crops prefer."
The study revealed a surprising mix of winners and losers depending on the projected global temperature. The "most likely" scenario projected by the International Panel on Climate Change is that global temperatures will rise 1.8 degrees Fahrenheit (1 degree Celsius) by 2030. In that scenario, the trade model projected relatively little change in crop yields, food prices and poverty rates.
But under the "low-yield" scenario, in which temperatures increase by 2.7 F (1.5 C), the model projects a 10 to 20 percent drop in agricultural productivity, which results in a 10 to 60 percent rise in the price of rice, wheat and maize. Because of these higher prices, the overall poverty rate in the 15 countries surveyed was expected to rise by 3 percent.
However, an analysis of individual countries revealed a far more compl
|Contact: Mark Shwartz|