
As experts in climate science, it’s our responsibility to tell you what we know. Climate change isn’t going to happen; it’s already 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 »As experts in climate science, it’s our responsibility to tell you what we know. Climate change isn’t going to happen; it’s already happening.