Monday, March 26, 2012
Global Temperatures Could Rise 5 Degrees by 2050
Where's the snow?
As the USA simmers through its hottest March on record — with more than 6,000 record high temperatures already set this month — a new study released Sunday shows that average global temperatures could climb 2.5 to 5.4 degrees by 2050 if greenhouse gas emissions continue unabated.
The study findings are based on the results of 10,000 computer model simulations of future weather overseen by researchers at Oxford University in the United Kingdom.
"These are the first results to suggest that the higher warming scenario could be plausible," says study lead author Dan Rowlands of Oxford.
It is a faster rate of warming than most other models predict.
Most scientists say that increasing amounts of carbon dioxide in the atmosphere from the burning of fossil fuels such as oil, gas and coal are causing the planet to warm to levels that cannot be explained by natural variability.
The study was published online Sunday in the journal Nature Geoscience and backs up similar predictions from the Intergovernmental Panel on Climate Change in 2007.
According to Rowlands, the climate model was the most complex used to date, and addresses some of the uncertainties that previous forecasts, using simpler models, may have overlooked.
"It's only by running such a large number of simulations — with model versions deliberately chosen to display a range of behavior — that you can get a handle on the uncertainty present in a complex system such as our climate," says Rowlands.
The climate models used in the study accurately reproduced actual, observed temperature changes over the last 50 years: Assuming that models that simulate past warming realistically are the best candidates for future warming predictions, the authors conclude in the study that a warming of from 2.5 to 5.4 degrees by 2050, compared with the 1960-90 average, is in the "likely range" of climate warming.