Dr. Roger Pielke pokes holes in the notion that global warming has caused increases in severe weather (hurricanes, tornadoes, blizzards, snow storms, flooding, extreme temperature changes) in the US or around the globe.

Published:  July 22, 2013 – 48:26

Dr. Roger Pielke, Jr.
Professor, Center for Science and Technology Policy Research
University of Colorado

Dr. Roy Spencer
Principal Research Scientist IV
University of Alabama, Huntsville

 

  • It is misleading, and just plain incorrect, to claim that disasters associated with hurricanes, tornadoes, floods or droughts have increased on climate timescales either in the United States or globally.
  • It is further incorrect to associate the increasing costs of disasters with the emission of greenhouse gases.
  • Globally, weather-related losses ($) have not increased since 1990 as a proportion of GDP (they have actually decreased by about 25%) and insured catastrophe losses have not increased as a proportion of GDP since 1960.
  • Hurricanes have not increased in the US in frequency, intensity or normalized damage since at least 1900. The same holds for tropical cyclones globally since at least 1970 (when data allows for a global perspective)
  • Floods have not increased in the US in frequency or intensity since at least 1950. Flood losses as a percentage of US GDP have dropped by about 75% since 1940.
  • Tornadoes have not increased in frequency, intensity or normalized damage since 1950, and there is some evidence to suggest that they have actually declined
  • Drought has “for the most part, become shorter, less frequent, and cover a smaller portion of
  • the U. S. over the last century.”
  • Globally, “there has been little change in drought over the past 60 years.”
  • The absolute costs of disasters will increase significantly in coming years due to greater wealth and populations in locations exposed to extremes. Consequent, disasters will continue to be an important focus of policy, irrespective of the exact future course of climate change.