Scientific Consensus | Facts – Climate Change: Vital Signs of the Planet – climate.nasa.gov

“Multiple studies published in peer-reviewed scientific journals1 show that 97 percent or more of actively publishing climate scientists agree*: Climate-warming trends over the past century are extremely likely due to human activities. In addition, most of the leading scientific organizations worldwide have issued public statements endorsing this position. The following is a partial list of these organizations, along with links to their published statements and a selection of related resources.

AMERICAN SCIENTIFIC SOCIETIES
Statement on climate change from 18 scientific associations
“Observations throughout the world make it clear that climate change is occurring, and rigorous scientific research demonstrates that the greenhouse gases emitted by human activities are the primary driver.”” (2009)2

Source: Scientific Consensus | Facts – Climate Change: Vital Signs of the Planet