claim: A recent study led by Lawrence Livermore National Laboratory climate scientist Ben Santer found that while the models ran hot, the ‘overestimation’ was ‘partly due to systematic deficiencies in some of the post-2000 external forcings used in the model simulations.’
evidence: A study published in the Journal of Geophysical Research in July 2007, titled Nuclear winter revisited with a modern climate model and current nuclear arsenals : Still catastrophic consequences, used current climate models to look at the consequences of a global nuclear war involving most or all of the world's current nuclear arsenals ( which the authors judged to be one similar to the size of the world's arsenals twenty years earlier ).