claim: The Schmittner et al. study finds low probability of both very low and very high climate sensitivities, and its lower estimate ( as compared to the IPCC ) is based on a new temperature reconstruction of the Last Glacial Maximum that may or may not withstand the test of time.
evidence: The Intergovernmental Panel on Climate Change ( IPCC, 2007 ) have produced a range of projections of what the future increase in global mean temperature might be.