Study: climate change means more heavy rain

Record rainfall led to disastrous flooding across much of Iowa in 2008, including the town of Cedar Rapids. Scientists say climate change will lead to an increase in heavy rainfall events for most of the world.

Climate change will lead to an increase in heavy rainfall events across most of the world, according to a study published this week in the peer-reviewed journal Proceedings of the National Academy of Sciences by researchers at the Massachusetts Institute of Technology and Caltech.

The computer models used in the study predict that areas such as North America can expect a significant increase in heavy rain.

How much rain? The study suggests that precipitation in extreme events will increase by about 6% for every 1.8 degree rise in global temperature. A global temperature increase of anywhere from 2 to 11 degrees is expected by 2100, according to the Intergovernmental Panel on Climate Change.

Overall, while the pattern is clear and consistent outside of the tropics, climate models give conflicting results within the tropics so more research will be needed to determine the outcomes in those regions.

The primary reason for the precipitation increase is that warmer air can retain more water vapor than cooler air. So as the climate heats up, "there will be more vapor in the atmosphere, which will lead to an increase in precipitation extremes," says study co-author Paul O'Gorman of MIT.

The USA Today article is here.