(See Correction & Amplification below .)
The National Academy of Sciences, a group of elite American researchers that advises the U.S. government, on Wednesday issued an 869-page report reasserting mankind's role in altering the climate and calling for specific policy measures to help forestall undesirable effects.
The report, requested by Congress 2008, essentially supports the main findings of the Intergovernmental Panel on Climate Change, a United Nations body whose most recent report released in 2007 was criticized for containing several errors.
Those errors and the publishing of unflattering emails hacked from a U.K. lab have put climate-change science in the hot seat in recent months.
"Climate change is occurring, is caused largely by human activities, and poses significant risks," the academy report concludes. The peer-reviewed study was done by 55 scientists from academia, industry and elsewhere vetted by the academy.
The next IPCC report will be in 2014. In some areas, the study provides a more up-to-date assessment of climate change. "We carefully looked at the scientific literature of the last five years, our own [academy] research," plus other sources, said Pamela Matson, dean of Stanford University's school of earth sciences, who helped compile the report.
Nonetheless, the academy acknowledged that there is significant uncertainty when attempting longer-term predictions about climate change.
For example, the 2007 IPCC report said sea levels could rise by between 0.6 and 1.9 feet by 2100, but later studies suggested that forecast was too conservative. The academy's report incorporates the newer research and concludes that sea levels could rise by as much as 6.5 feet in that period.
The new report also urges the U.S. to take bold steps to cut fossil-fuel use, calling for a carbon tax on such fuels—mainly oil and coal—or a cap-and-trade system, which offers monetary incentives to cut emissions of pollutants. Those recommendations are a big step up from the less-sharply-worded prescriptions issued by the academy in the past.
"The charge we got from Congress was not just to tell them what the science says but what to do about the problem," said Robert Fri, a visiting scholar at the nonprofit Resources for the Future, who helped compile the report.
The report says that the U.S. emissions of between 170 billion to 200 billion tons of carbon dioxide equivalent from 2012 until 2050 would be a "reasonable goal," in line with reduction targets proposed by the White House. In 2008, the U.S. emitted about seven billion tons of carbon-dioxide equivalent.At that rate, the U.S. will run through the suggested emission amounts well before 2050, the academy said.
Write to Gautam Naik at email@example.com
Correction & Amplification
The National Academy of Sciences on Wednesday issued a report about climate change. A previous version of this article incorrectly identified the organization as the National Academy of Scientists.