In his recent press blitz, NASA’s James Hansen tries to tie extreme weather events, such the current drought affecting much of the central U.S., to anthropogenic global warming. But the real world argues otherwise.
Hansen is quite adept at timing global warming pronouncements with extreme weather events. Recall that it was during a similar hot, dry period back in the summer of 1988 that Hansen first testified to Congress that global warming from human greenhouse gas emissions was impacting current weather events—testimony which many credit as giving rise to the global-warming-is-going-to-be-bad movement. But then, as now, the tie-in between weather events and human changes to the atmospheric greenhouse effect is tenuous at best, and tie-ins to specific events are ill-supported and ill-advised. In the best case, the anthropogenic emissions-driven rise in global temperatures has a small ancillary impact on a specific extreme weather event, but in the vast majority of the cases, its role is nugatory and undetectable.