A level of no more than 350 ppm is still feasible, with the help of reforestation and improved agricultural practices, but just barely - time is running out.

Policy decisions on climate change are being deliberated every day by those without full knowledge of the science, and often with intentional misinformation spawned by special interests.

'Goals' and 'caps' on carbon emissions are practically worthless, if coal emissions continue, because of the exceedingly long lifetime of carbon dioxide in the air.

...chief executives of large fossil fuel companies to [should] be put on trial for high crimes against humanity and nature; [Hansen] accusing them of actively spreading doubt about global warming in the same way that tobacco companies blurred the links between smoking and cancer.

The carbon emissions from tar shale and tar sands would initiate a continual unfolding of climate disasters over the course of this century. We would be miserable stewards of creation. We would rob our own children and grandchildren.

The trains carrying coal to power plants are death trains. Coal-fired power plants are factories of death.

Interference with communications of science to the public has been greater during the current administration than at any time in my career.