James Hansen’s research paper linking extreme weather with global warming

5/4/2012 Public Perception of Climate Change and the New Climate Dice. by James Hansen, Makiko Sato, Reto Ruedy.“Climate dice”, describing the chance of unusually warm or cool seasons relative to climatology, have become progressively “loaded” in the past 30 years, coincident with rapid global warming. The distribution of seasonal mean temperature anomalies has shifted toward higher temperatures and the range of anomalies has increased. An important change is the emergence of a category of summertime extremely hot outliers, more than three standard deviations (3{\sigma}) warmer than climatology. This hot extreme, which covered much less than 1% of Earth’s surface in the period of climatology, now typically covers about 10% of the land area. It follows that we can state, with a high degree of confidence, that extreme anomalies such as those in Texas and Oklahoma in 2011 and Moscow in 2010 were a consequence of global warming, because their likelihood in the absence of global warming was exceedingly small. We discuss practical implications of this substantial, growing, climate change.
(Submitted on 5 Apr 2012)

19 pages, 12 figures; submitted to Proceedings of the National Academy of Sciences

Subjects: Atmospheric and Oceanic Physics (

Cite as: arXiv:1204.1286v1 []
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