In a recent paper , Pushker Kharecha and James Hansen called for “expanding the role of nuclear power” as a clear necessity in order to avoid “devastating climate impacts” from greenhouse gases:
“…it is clear that nuclear power has provided a large contribution to the reduction of global mortality and GHG emissions due to fossil fuel use. If the role of nuclear power significantly declines in the next few decades, the International Energy Agency asserts that achieving a target atmospheric GHG level of 450 ppm CO2-eq would require ‘heroic achievements in the deployment of emerging low-carbon technologies, which have yet to be proven. Countries that rely heavily on nuclear power would find it particularly challenging and significantly more costly to meet their targeted levels of emissions.’ Our analysis herein and a prior one strongly support this conclusion. Indeed, on the basis of combined evidence from paleoclimate data, observed ongoing climate impacts, and the measured planetary energy imbalance, it appears increasingly clear that the commonly discussed targets of 450 ppm and 2° C global temperature rise (above preindustrial levels) are insufficient to avoid devastating climate impacts; we have suggested elsewhere that more appropriate targets are less than 350 ppm and 1°C (refs 3 and 31−33). Aiming for these targets emphasizes the importance of retaining and expanding the role of nuclear power, as well as energy efficiency improvements and renewables, in the near-term global energy supply.”
 Kharecha, P.A., and J.E. Hansen, 2013: “Prevented mortality and greenhouse gas emissions from historical and projected nuclear power.” Environ. Sci. Technol., 47, 4889-4895, doi:10.1021/es3051197.
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