There is an article in the November 3 2009 issue of EOS titled “Science Organizations Remind Senators of the Consensus on Climate Change” by K. Chell [subscription required]. The letter is signed by the leadership of American Association for the Advancement of Science, American Chemical Society, American Geophysical Union, American Institute of Biological Sciences, American Meteorological Society, American Society of Agronomy, American Society of Plant Biologists, American Statistical Association, Association of Ecosystem Research Centers, Botanical Society of America, Crop Science Society of America, Ecological Society of America, Natural Science Collections Alliance, Organization of Biological Field Stations, Society for Industrial and Applied Mathematics, Society of Systematic Biologists, Soil Science Society of America, and the University Corporation for Atmospheric Research.
The letter reads
October 21, 2009
As you consider climate change legislation, we, as leaders of scientific organizations, write to state the consensus scientific view.
Observations throughout the world make it clear that climate change is occurring, and rigorous scientific research demonstrates that the greenhouse gases emitted by human activities are the primary driver. These conclusions are based on multiple independent lines of evidence, and contrary assertions are inconsistent with an objective assessment of the vast body of peer-reviewed science. Moreover, there is strong evidence that ongoing climate change will have broad impacts on society, including the global economy and on the environment. For the United States, climate change impacts include sea level rise for coastal states, greater threats of extreme weather events, and increased risk of regional water scarcity, urban heat waves, western wildfires, and the disturbance of biological systems throughout the country. The severity of climate change impacts is expected to increase substantially in the coming decades.
If we are to avoid the most severe impacts of climate change, emissions of greenhouse gases must be dramatically reduced. In addition, adaptation will be necessary to address those impacts that are already unavoidable. Adaptation efforts include improved infrastructure design, more sustainable management of water and other natural resources, modified agricultural practices, and improved emergency responses to storms, floods, fires and heat waves.
We in the scientific community offer our assistance to inform your deliberations as you seek to address the impacts of climate change.
Footnote to paragraph 2
The conclusions in this paragraph reflect the scientific consensus represented by, for example, the Intergovernmental Panel on Climate Change and U.S. Global Change Research Program. Many scientific societies have endorsed these findings in their own statements, including the American Association for the Advancement of Science, American Chemical Society, American Geophysical Union, American Meteorological Society, and American Statistical Association. We in the scientific community offer our assistance to inform your deliberations as you seek to address the impacts of climate change.
This statement (which was not voted on by the membership in the professional organizations that I am a member) contains a fundamental factual error in the view of a significant number of climate scientists. Specifically, the statements that “rigorous scientific research demonstrates that the greenhouse gases emitted by human activities are the primary driver. These conclusions are based on multiple independent lines of evidence, and contrary assertions are inconsistent with an objective assessment of the vast body of peer-reviewed science.”
Such a conclusion needs to be viewed as a hypothesis. If so , examples that refute the hypothesis is all that is need to reject its validity. This has been done, as has been discussed recently in several weblog posts; e.g. see
The reason that these professional organizations claim there is a consensus is that the very limited individuals who make these policy statements do not permit their membership to vote, or to present alternative viewpoints. The Senators to whom this letter were addressed should reach out for a broader range of inputs with respect to the role of humans in the climate system.
As we concluded in our EOS article
Pielke Sr., Roger, Keith Beven, Guy Brasseur, Jack Calvert, Moustafa Chahine, Russ Dickerson, Dara Entekhabi, Efi Foufoula-Georgiou, Hoshin Gupta, Vijay Gupta, Witold Krajewski, E. Philip Krider, William K. M. Lau, Jeff McDonnell, William Rossow, John Schaake, James Smith, Soroosh Sorooshian, and Eric Wood: 2009: “Climate Change: The Need to Consider Human Forcings Besides Greenhouse Gases“. Eos, Vol. 90, No. 45, 10 November 2009, page 413. This paper was published by AGU EOS [subscription required for the version as it appears in EOS – Copyright (2009) American Geophysical Union];
“[a]lthough the natural causes of climate variations and changes are undoubtedly important, the human influences are significant and involve a diverse range of first- order climate forcings, including, but not limited to, the human input of carbon dioxide (CO2). Most, if not all, of these human influences on regional and global climate will continue to be of concern during the coming decades”
“In addition to greenhouse gas emissions, other first- order human climate forcings are important to understanding the future behavior of Earth’s climate. These forcings are spatially heterogeneous and include the effect of aerosols on clouds and associated precipitation [e.g., Rosenfeld et al., 2008], the influence of aerosol deposition (e.g., black carbon (soot) [Flanner et al. 2007] and reactive nitrogen [Galloway et al., 2004]), and the role of changes in land use/land cover [e.g., Takata et al., 2009]. Among their effects is their role in altering atmospheric and ocean circulation features away from what they would be in the natural climate system [NRC, 2005]. As with CO2, the lengths of time that they affect the climate are estimated to be on multidecadal time scales and longer.”
The claim in the Letter to the Senators that “rigorous scientific research demonstrates that the greenhouse gases emitted by human activities are the primary driver. These conclusions are based on multiple independent lines of evidence, and contrary assertions are inconsistent with an objective assessment of the vast body of peer-reviewed science” is incorrect, as documented above.