I found this
at Fred Honsberger's favorite on-line news service, CNSNews.com.
A new survey of American members of the United Nation's Intergovernmental Panel on Climate Change (IPCC) suggests that there is not firm scientific consensus on global warming, as proponents of swift action to curb carbon emissions have suggested.
DemandDebate.com, a Web site skeptical of global warming "alarmism" that advocates more debate on the topic, released the results of its poll on Nov. 8. The group attempted to survey the 345 American scientists affiliated with the IPCC.
Of the 54 scientists who completed the survey, less than half said a 1-degree Celsius increase is "flatly undesirable." Sixty-one percent of the respondents said there is no such thing as an "ideal climate.
Please note the sloppy terminology. DemandDebate.com sent out the survey to "the 345 American scientists affiliated with the IPCC." The IPCC, by the way is the "Intergovernmental
Panel on Climate Change." It is "Intergovernmental" on account that it's comprised of scientists from more than one country. Of the 345 surveys sent out to American
scientists, DemandDebate.com received only 54.
How many scientists were affiliated with IPCC in the first place? The IPCC website
says 2,500 scientific expert reviewers, 800 contributing authors, and 450 lead authors were involved in the IPCC 4th assessment. If that number is accurate and consistent with the other reports, there are about 3,750 scientists involved making IPCC reports.
And yet DemandDebate.com is using a self-filtered survey (i.e. it doesn't cover the whole population of scientists affiliated with the IPCC and it's only based on those surveys returned) of about 1.4% of those scientists to "suggest" that there's no firm consensus on climate change.
But look at what CNSNews glosses over. It's the very next paragraph:
While as many as 90 percent of respondents said man-made carbon emissions "are driving or helping to drive global climate change," only 20 percent said human activity is the "principle driver of climate change." Sixty-three percent said human activity is a driver but that "natural variability is also important."
Let's take a closer look at this "data." The first question in this survey was:
Which best describes the reason(s) for climate change?
It then listed the 4 options (with a "No Opinion" tagged on the end) available. Here they are (with the percentages of those who chose that option):
- Human activity is the principal driver of climate change. 20%
- Human activity drives climate change, but natural variability is also important. 63%
- Natural variability drives climate change, but human activity is also important. 11%
- Natural variability is the principal driver of climate change. 4%
- No opinion. 2%
So 94% of those surveyed believe that at the very least "human activity is...important" in describing the reasons for climate change. 83% think that it either "drives" climate change or is the "principle driver." Honestly, I'm not sure what the difference between those two are - but let's just chalk that up to clumsy word usage.
These folks are basing their claim suggesting there isn't a consensus (even though from the first question in this already flawed survey, it's pretty obvious that there is) on two questions at the end; on the impact of a 1 celsius rise in mean global temperature (48% say it's "undesirable" and 39% say it's "desirable for some, undesirable for others") and whether there's an "ideal" global climate (61% says there's no such thing).
Huh. Go figure.
For another view on this, let's take a look at this article
from the magazine "Science
" which describes itself as "The world's leading journal of original scientific research, global news, and commentary."
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 [the report] 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. ... [M]ost of the observed warming over the last 50 years is likely to have been due to the increase in greenhouse gas concentrations" [p. 21 in (4)].
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" [p. 1 in (5)]. 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" [p. 3 in (5)].
But to test things, they did a little experiment of sorts:
That hypothesis was tested by analyzing 928 abstracts, published in refereed scientific journals between 1993 and 2003, and listed in the ISI database with the keywords "climate change" (9).
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.