Feb 16, 2011 11:06 PM GMT
Here's some food for thought for all those who invoke posterity for their actions:
http://hosted.ap.org/dynamic/stories/U/US_SCI_CLIMATE_FLOODS?SITE=NYSAR&SECTION=HOME&TEMPLATE=DEFAULTWASHINGTON (AP) -- Extreme rainstorms and snowfalls have grown substantially stronger, two studies suggest, with scientists for the first time finding the telltale fingerprints of man-made global warming on downpours that often cause deadly flooding.
Two studies in Wednesday's issue of the journal Nature link heavy rains to increases in greenhouse gases more than ever before.
One group of researchers looked at the strongest rain and snow events of each year from 1951 to 1999 in the Northern Hemisphere and found that the more recent storms were 7 percent wetter. That may not sound like much, but it adds up to be a substantial increase, said the report from a team of researchers from Canada and Scotland.
Not all the extreme rain and snow events the scientists studied cause flooding. But since 1950, flooding has killed more than 2.3 million people, according to the World Health Organization's disaster database.
The British study focused on flooding in England and Wales in the fall of 2000. The disaster cost more than $1.7 billion in insured damages and was the wettest autumn for the region in more than 230 years of record-keeping.
The scientists took all the information that shows an increase in extreme rain and snow events from the 1950s through the 1990s and ran dozens of computer models numerous times. They put in the effects of greenhouse gases - which come from the burning of fossil fuels - and then ran numerous models without those factors. Only when the greenhouse gases are factored in do the models show a similar increase to what actually happened. All other natural effects alone don't produce the jump in extreme rainfall. Essentially, the computer runs show climate change is the only way to explain what's happening.
In fact, the computer models underestimated the increase in extreme rain and snow. That is puzzling and could be even more troubling for our future, said Michael Oppenheimer of Princeton University, who wasn't part of the study.