Climate change means more rain, snow for some
Saturday afternoon thundershower in Shanghai. (Photo: jiji)
In a warming world, places with lots of rain and snowfall might get even more.
And dry places might get drier. Earth & Sky spoke to Francis Zwiers, Director of the Climate Research Division of the federal agency Environment Canada. He said to expect more precipitation in high latitudes, both in the northern hemisphere and in the southern hemisphere – and to expect less precipitation in areas that are currently dry, in the subtropics.
Francis Zwiers: So essentially, the rich get richer – those who have a lot of precipitation will get more precipitation in the future – and the poor get poorer.
Zwiers explained that as Earth warms, the atmosphere can hold more moisture in the form of water vapor. He said this has already started to happen. That moisture is circulated worldwide from the subtropics to the tropics and high latitudes. A still-warmer climate revs up that circulation, Zwiers said.
Francis Zwiers: So even in places where the climate dries, the chances of when a heavy downpour occurs – a downpour that might cause local flooding, damage to storm sewer systems, that type of thing – those events when they occur are likely to be more extreme in a warmer climate.
One area that might get drier is the western U.S. in summertime. Your thoughts on Earth’s changing climate? You can tell us in the comments section below.
Canadian Centre for Climate Modelling and Analysis, Francis Zwiers
The Science of Climate Change, from Environment Canada
Climatically-Induced Increases in Water Vapor and Precipitation: Causation and Implications, seminar given by the American Meteorological Society, Oct. 29, 2007, in Washington, DC.
The Physical Science Basis of Climate Change, (summary for policymakers), Intergovernmental Panel on Climate Change
Our thanks to:
Francis W. Zwiers, Ph.D.
Director Climate Research Division
Environment Canada
Toronto, Ontario
NEW! Find related content with Sphere
I lived in the desert of the Southwest and I can’t imigine it getting dryer! The biggest downpour occured in Phoenix in the 1920’s. I have since moved to Texas where we have had the wettest year (the old timers say) in many years, only riveled by hurricanes only we have had no hurricanes where I live.
when the west does dry up (and it will, history can prove that), where will the huge populations that occupy that area go to? they’ve nearly tapped out their sources for water. when can we expect the return of the “black blizzards”?