New Study Doubles Global Warming Prediction
By J.R. Pegg
WASHINGTON, DC, January 28, 2005 (ENS) - Human emissions of greenhouse gases could cause global temperatures to rise some 11 degrees Celsius (20 degrees Fahrenheit) by century's end, according to results from the world's largest climate prediction experiment.
The findings, published Thursday in the journal "Nature," project a potential temperature increase more than double the amount predicted by the Inter-Governmental Panel on Climate Change (IPCC).
"The possibility of such high responses has profound implications," said Dr. David Frame of Oxford University, coordinator of the Climateprediction.net project. "If the real world response were anywhere near the upper end of our range, even today's levels of greenhouse gases could already be dangerously high."
Climateprediction.net is a simulation project harnessing the power of idle PCs to forecast the climate of the 21st century.
The analysis published in "Nature" uses more than 2,000 unique simulations of the climate, each of which was then set up to respond to a doubling of atmospheric CO2 levels.
All of the simulations predicted temperature increases.
The results of the experiment show the higher temperature increase could occur even if carbon dioxide levels in the atmosphere are limited to twice the 280 parts per million (ppm) found before the industrial revolution.
Unless major cuts are made in greenhouse gas emissions, that level is likely to be reached by 2050.
"Our experiment shows that increased levels of greenhouse gases could have a much greater impact on climate than previously thought," said Oxford's David Stainforth, chief scientist for Climateprediction.net.
The findings are the first from a unique effort to explore a wide range of uncertainties to formulate more realistic global warming predictions.
The ongoing Climateprediction.net project, created by Oxford University researchers and supported by the U.K. Natural Environment Research Council, began in September 2003 involves more than 95,000 people from more than 140 countries.
Volunteers download free software that runs the climate modeling program when their computers are idle.
The program runs through a climate scenario and automatically reports the results to climate researchers at Oxford and collaborating institutions.
The method has enabled researchers to overcome a major barrier to climate modeling - computer space.
The result is "an experiment which would otherwise been impossible," said Dr. Andrew Martin of the Oxford e-Science Center.
The researchers plan to continue refining simulations and working on the model.
The findings come on the heels of another study that warned the world is running out of time to avoid serious impacts from global warming.
Dramatic efforts are needed in the next decade, the International Climate Change Task Force said Monday, if the world is to avoid the rising sea levels, agricultural losses, increased water shortages and widespread adverse health impacts expected from global warming.
Those impacts will likely occur unless the world can limit the average temperature rise to 2 degrees Celsius (3.6 degrees Fahrenheit) above the average level found prior to the industrial revolution.
The task force says the world is very close to the level of carbon dioxide (CO2) in the atmosphere - 400 parts per million (ppm) - that will make a two degree Celsius rise inevitable.
Atmospheric CO2 is rising more than two ppm a year and is already some 380 ppm.
Information about the Climateprediction.net experiment can be found here.
See a poster presentation on Climateprediction.net here.