The Intergovernmental Panel on Climate Change—the IPCC—is the most respected body in the world when it comes to evaluating the science of climate change.
1941 different countries are represented by thousands of scientists who contribute their expertise in writing and reviewing IPCC reports.
As the name implies, governments also have a hand in shaping the reports produced.
Because of this the findings of the IPCC are never exaggerations. Their reports are conservative to a fault, even calibrating their language so that readers know that when they use the phrase “very likely” they mean there is a greater than 90% likelihood.
Their first report came out in 1990 and the most recent was their forth report in 2007.
The IPCC won’t say anything unless they’re damn sure it’s true.
Because of this with every new IPCC report their assertions on climate change get more and more definite and more and more alarming.
The fifth IPCC report is due to appear in 2014.
Footnote 1) according to Raymond S. Bradley’s book Global Warming and Political Intimidation