The Scientific Consensus On Climate Change

[RestoreGore]

For those who still insist on continuing to attack Al Gore for being the effective missive he is in bringing the fact that there is scientific consensus on anthropogenic climate change to those who need to know it. I would suggest that those who belong to the Flat Earth Society and the Gold Bars Club give it a real hard look as you do a true disservice to this planet and its inhabitants with your continuing denial, moral deafness, greed, and political rhetoric.

Bolding is my emphasis.
~~
http://www.earth.columbia.edu/grocc/documents/Oreskes-TheScientificConsensusonClimateChange.pdf
By Naomi Oreskes

Policy-makers and the media, particularly in the United States, frequently assert that climate science is highly uncertain. Some have used this as an argument against adopting strong measures to reduce greenhouse gas emissions. For example, while discussing a major U.S. Environmental Protection Agency report on the risks of climate change, then–EPA administrator Christine Whitman argued, “As went through review, there was less consensus on the science and conclusions on climate change” (1).

Some corporations whose revenues might be adversely affected by controls on carbon dioxide emissions have also alleged major uncertainties in the science (2). Such statements suggest that there might be substantive disagreement in the scientific community about the reality of anthropogenic climate change. This is not the case. The scientific consensus is clearly expressed in the reports of the Intergovernmental Panel on Climate Change (IPCC). Created in 1988 by the World Meteorological Organization and the United Nations Environmental Programme, IPCC’s purpose is to evaluate the state of climate science as a basis for informed policy action, primarily on the basis of peer-reviewed and published scientific literature (3).

In its most recent assessment, IPCC states unequivocally that the consensus of scientific opinion is that Earth’s climate is being affected by human activities: “Human activities … are modifying the concentration of atmospheric constituents … that absorb or scatter radiant energy. … ost of the observed warming over the last 50 years is likely to have been due to the increase in greenhouse gas concentrations” . IPCC is not alone in its conclusions. In recent years, all major scientific bodies in the United States whose members’ expertise bears directly on the matter have issued similar statements. For example, the National Academy of Sciences report, Climate Change Science: An Analysis of Some Key Questions, begins: “Greenhouse gases are accumulating in Earth’s atmosphere as a result of human activities, causing surface air temperatures and subsurface ocean temperatures to rise” . The report explicitly asks whether the IPCC assessment is a fair summary of professional scientific thinking, and answers yes: “The IPCC’s conclusion that most of the observed warming of the last 50 years is likely to have been due to the increase in greenhouse gas concentrations accurately reflects the current thinking of the scientific community on this issue” .

snip

The 928 papers were divided into six categories:
explicit endorsement of the consensus

position,

evaluation of impacts,

mitigation proposals,

methods,

paleoclimate analysis,

and rejection of the consensus position.

Of all the papers, 75% fell into the first three categories, either explicitly or implicitly accepting the consensus view; 25% dealt with methods or paleoclimate, taking no position on current anthropogenic climate change. Remarkably, none of the papers disagreed with the consensus position. Admittedly, authors evaluating impacts, developing methods, or studying paleoclimatic change might believe that current climate change is natural. However, none of these papers argued that point.

This analysis shows that scientists publishing in the peer-reviewed literature agree with IPCC, the National Academy of Sciences, and the public statements of their professional societies. Politicians, economists, journalists, and others may have the impression of confusion, disagreement, or discord among climate scientists, but that impression is incorrect. The scientific consensus might, of course, be wrong. If the history of science teaches anything, it is humility, and no one can be faulted for failing to act on what is not known. But our grandchildren will surely blame us if they find that we understood the reality of anthropogenic climate change and failed to do anything about it.

Many details about climate interactions are not well understood, and there are ample grounds for continued research to provide a better basis for understanding climate dynamics. The question of what to do about climate change is also still open. But there is a scientific consensus on the reality of anthropogenic climate change. Climate scientists have repeatedly tried to make this clear. It is time for the rest of us to listen.

References and Notes
1. A. C. Revkin, K. Q. Seelye, New York Times, 19 June
2003, A1.
2. S. van den Hove, M. Le Menestrel, H.-C. de Bettignies,
Climate Policy 2 (1), 3 (2003).
3. See www.ipcc.ch/about/about.htm.
4. J. J. McCarthy et al., Eds., Climate Change 2001:
Impacts, Adaptation, and Vulnerability (Cambridge
Univ. Press, Cambridge, 2001).
5. National Academy of Sciences Committee on the
Science of Climate Change, Climate Change Science:
An Analysis of Some Key Questions (National
Academy Press,Washington, DC, 2001).
6. American Meteorological Society, Bull. Am. Meteorol.
Soc. 84, 508 (2003).
7. American Geophysical Union, Eos 84 (51), 574 (2003).
8. See www.ourplanet.com/aaas/pages/atmos02.html.
9. The first year for which the database consistently
published abstracts was 1993. Some abstracts were
deleted from our analysis because, although the authors
had put “climate change” in their key words, the
paper was not about climate change.
10. This essay is excerpted from the 2004 George Sarton
Memorial Lecture, “Consensus in science: How do we
know we’re not wrong,” presented at the AAAS meeting
on 13 February 2004. I am grateful to AAAS and
the History of Science Society for their support of
this lectureship; to my research assistants S. Luis and
G. Law; and to D. C. Agnew, K. Belitz, J. R. Fleming, M.
T. Greene, H. Leifert, and R. C. J. Somerville for helpful
discussions.

[RestoreGore]

1. Greenland Ice Sheet Losing Mass

http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17434