What We Know
Based on the evidence, about 97% of climate scientists agree that human-caused climate change is happening.
Based on the evidence, about 97% of climate experts have concluded that human-caused climate change is happening. What We Know helps us understand the science behind the realities, risks and response to the climate challenge.
Read the Backgrounder »Understanding science is our work. Our consensus is that climate change is happening and the risks are real. Learn more about AAAS and the What We Know initiative.
In 2019, AAAS launched the How We Respond project: a report and multimedia stories highlighting U.S. communities that are actively and effectively responding to climate change.