Roger Pielke Jr: A Factual Look At The Relationship Of Climate And Weather

  • Date: 16/12/13
  • Roger Pielke Jr.

Testimony by Professor Roger Pielke Jr. to the Subcommittee on Environment of the Committee on Science, Space, and Technology of the United States House of Representatives

 

Take-Home Points

* There exists exceedingly little scientific support for claims found in the media and political debate that hurricanes, tornadoes, floods and drought have increased in frequency or intensity on climate timescales either in the United States or globally.

Similarly, on climate timescales it is incorrect to link the increasing costs of disasters with the emission of greenhouse gases.

These conclusions are supported by a broad scientific consensus, including that recently reported by the Intergovernmental Panel on Climate Change (IPCC) in its fifth assessment report (2013) as well as in its recent special report on extreme events (2012).

Here are some specific conclusions, with further details provided below:

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.

Hurricane landfalls 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 in the US 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.
Full testimony

The short hearing can be viewed in full here: