America's top scientists call for carbon trading system

Posted by Emma Woollacott

The National Academy of Sciences (NAS) is continuing its crusade for more action on climate change by publishing three reports calling for  prices to be put on carbon emissions.

The three reports confirm the view of the overwhelming majority of scientists that the world is now 1.4 degrees warmer than a century ago, and that human activity is likely to increase this by anything between two and 11 degrees more by 2100.

"There are reasons for the uncertainty. First, these are based on estimates on human activities - how do we use energy, how will we use land, how will our economies grow," said Pamela Matson, dean of Stanford University's school of earth sciences.

The project was requested by Congress more than two years ago and represents the thoughts of more than 90 eminent scientists.

"Together these reports demonstrate that the state of climate science is strong and also underline the fact that the scientific community needs to continue to expand on its understanding of why climate change is happening and focus on when and where the most important impacts will occur," said Ralph Cicerone, president of the National Academy of Sciences.

The reports call for a cut in US carbon emissions of between 50 and 80 percent by 2050 - in line with targets set by both the Bush and Obama legislations.

They say the best way to do this is through a cap-and-trade system. This would set national limits on carbon dioxide emissions, but would allow companies to pollute more by buying carbon credits from less-polluting organizations.

They also call for better coordination of federal research, through a new agency - possibly a beefed-up US Global Change Research Program.

And they incude suggestions as to how to deal with the effects of climate change, such as moving vulnerable populations away from the coast.

The three reports - Advancing the Science of Climate Change, Limiting the Magnitude of Climate Change and Adapting to the Impacts of Climate Change - are available here. A fourth report will be released later this year.

Earlier this month, the NAS published an open letter defending climate science and trying to educate the public on the scientfic method.