James Hansen - We conclude that Earth in the warmest interglacial periods was less than 1°C warmer than in the Holocene and that goals of limiting human-made warming to 2°C and CO2 to 450 ppm are prescriptions for disaster.

Rapid reduction of fossil fuel emissions is required for humanity to succeed in preserving a planet resembling the one on which civilization developed.

Robert Bryce is a senior fellow at the Center for Energy Policy and the Environment at the Manhattan Institute. In theory, the March 11, 2011, disaster at the Fukushima Daiichi nuclear plant should have bolstered environmentalists’ opposition to new nuclear-energy projects. But in the wake of the worst nuclear accident since Chernobyl, some of the world’s leading Greens have done just the opposite: they have come out in favor of nuclear power.

Judith Curry, PhD Geophysical Sciences, University of Chicago, Professor at the School of Earth and Atmospheric Sciences, Georgia Institute of Technology. Over 30 year career in atmospheric science. The magnitude of climate effects caused by using fossil fuels is questionable. Physical data does not agree with the climate models and most likely will be less than they predict. .