Here is the letter from 18 top U.S. scientific organizations:
As you consider climate change legislation, we, as leaders of scientific organizations, write to state the consensus scientific view.
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.
These conclusions are based on multiple independent lines of evidence, and contrary assertions are inconsistent with an objective assessment of the vast body of peer-reviewed science. Moreover, there is strong evidence that ongoing climate change will have broad impacts on society, including the global economy and on the environment. For the United States, climate change impacts include sea level rise for coastal states, greater threats of extreme weather events, and increased risk of regional water scarcity, urban heat waves, western wildfires, and the disturbance of biological systems throughout the country. The severity of climate change impacts is expected to increase substantially in the coming decades. [See Footnote #1 below]
If we are to avoid the most severe impacts of climate change, emissions of greenhouse gases must be dramatically reduced. In addition, adaptation will be necessary to address those impacts that are already unavoidable. Adaptation efforts include improved infrastructure design, more sustainable management of water and other natural resources, modified agricultural practices, and improved emergency responses to storms, floods, fires and heat waves.
We in the scientific community offer our assistance to inform your deliberations as you seek to address the impacts of climate change.
Well it’s a start (see “Publicize or perish: The scientific community is failing miserably in communicating the potential catastrophe of climate change“). But I still prefer the Bali declaration by more than 200 of the world’s leading climate scientists, which embraces the 2°C target and specific emissions reductions targets.
The footnote reads: