Atlas Monitor | 16 June 2014
Some detail and nuance is required in this discussion.
The often cited “97% of scientists agree global warming is happening and caused by human activity” deserves some examination.
A 2009 study by Doran & Zimmerman from the University of Illinois conducted an online survey whereby they invited 10,000 scientists to answer a series of questions. Two questions were of primary importance:
“Q1. “When compared with pre-1800s levels, do you think that mean global temperatures
have generally risen, fallen, or remained relatively constant?”
Q2. “Do you think human activity is a significant contributing factor in changing mean
This generated responses from just over 3000 scientists from which they took 79 (not a typo) respondents to form the basis of their study.
98% responded temperatures had “generally risen” to Q1 and “yes” to Q2. However no question was asked referring specifically to CO2.
Even sceptics would likely answer similarly to Q1 & Q2 as they also acknowledge that one would expect to see temperatures rise coming out of the well documented “Little Ice Age” (LIA) and that equally well documented phenomena such as the Urban Heat Island Effect (UHIE) which demonstrates that temperatures are warmer in urban areas of increased human activity than in the countryside where there is comparatively less.
Apart from the remarkably small sample size, further problems are evident in the study. Those being that the issue is not whether or not temperatures have risen since the LIA or whether there is a human impact but whether the warming is unusual in rate or magnitude, whether the part attributable to humans is good or bad (how good or how bad) and whether the benefits of reducing human contribution outweighs the costs. On this the study is silent.
And again no question was asked about CO2.
This study is often conflated with another study done in 2010 (Anderegg et al) which included 200 “climate researchers” (loosely defined to include people who had merely signed a petition supporting the UN Intergovernmental Panel on Climate Change [IPCC]’s position) as the basis of its study. It found that 97-98% of the “climate researchers” believed that “anthropogenic greenhouse gases have been responsible for ‘most’ of the ‘unequivocal’ warming of the Earth’s average global temperature over the second half of the 20th century.”
Apart from loose definition of “climate researcher” other problems with this study include: that it did not ask whether or not the sample thought global warming was a crisis or that the science is sufficiently established to be the basis of public policy.
A meta-analysis of just under 12,000 abstracts of scientfic papers conducted by a team of scientists led by John Cook claimed that 97% supported the Anthropogenic Global Warming (AGW) theory. However, this study misclassified several papers by prominent climate skeptics, as agreeing with the so-called consensus when they in fact did not, in order to contrive a predetermined outcome.
In summary none of these studies support the claim that “97% of scientists believe in man-made global warming”. The Doran & Zimmerman sample was too small and did not mention CO2; the Anderegg et al sample cannot be regarded as “expert”; and Cook et al raises some serious questions of legitimacy and credibility, if not scientific ethics.
Furthermore the datasets used by the IPCC to publish its assessment reports ie NASA, HadCRUT, NOAA etc demonstrate that there has been no warming trend for going on 17 years but in fact a discernible cooling trend (recently acknowledged by IPCC chief Rajendra Pachauri). This has occurred during a period of increased CO2 emmissions. The IPCC admits that manmade global warming can only have occurred in the last 20 years. The fact that climate models failed to predict this is extraordinary and demonstrates their limitations.
University of Illinois data shows that there has been no change in the amount of sea ice on average and NOAA data shows no change in land falling Atlantic hurricanes in the US for 150 years and the combined frequency, duration and intensity of all hurricanes, typhoons and tropical cyclones around the world reached the lowest point in 30 years up to 2009.
Another claim that CO2 levels of 400 ppm is unprecedented in patently false. In fact CO2 has reached that level twice in the last 200 years according to respected meteorologist and astrophysicist Piers Corbyn who has an unprecedented accuracy rate for predicting weather up to a year in advance. In fact CO2 levels have not only been much higher in the past but there is in fact little scientific basis to the linear relationship between CO2 and temperature.
In 2009 one hundred scientists put their names to a newspaper advertisement challenging Obama’s assertions that the science was beyond dispute. They protested:
We, the undersigned scientists, maintain that the case for alarm regarding climate change is grossly overstated. Surface temperature changes over the past century have been episodic and modest and there has been no net global warming for over a decade now. After controlling for population growth and property values, there has been no increase in damages from severe weather-related events. The computer models forecasting rapid temperature change abjectly fail to explain recent climate behavior. Mr. President, your characterization of the scientific facts regarding climate change and the degree of certainty informing the scientific debate is simply incorrect.
By 2010 the number of dissenting scientists prepared to go public had risen to 1000. Some of them were former UN IPCC scientists who had arrived at differnet conclusions to their colleauges. In a report to the US Congress they emphasized that
More than 1,000 dissenting scientists from around the globe have now challenged man-made global warming claims made by the United Nations Intergovernmental Panel on Climate Change and former Vice President Al Gore.
It should be noted that this is 20 times the number of the 52 scientists that co-authoured the 2007 UN IPCC Summary for Policy Makers. It is also more than 79 respondents picked for the Doran and Zimmerman study and the 200 people used in the Anderegg et al survey.
The Global Warming Petition Project has been signed by 31,487 scientists including 9,029 with PhDs in their fields. The petition states that:
There is no convincing scientific evidence that the human release of carbon dioxide, methane, or other greenhouse gases is causing or will, in the foreseeable future, cause catastrophic heating of the Earth’s atmosphere and disruption of the Earth’s climate. Moreover, there is substantial scientific evidence that increases in atmospheric carbon dioxide produce many beneficial effects upon the natural plant and animal environments of the Earth.
This petition project will by no means be immune to problems however the point is :
The claim that the science is settled has no basis in science and is a profoundly unsupportable assertion. The alarmist claims have no basis in science. There is no scientific basis from which to formulate public policy – and that is of the utmost concern.
The Great Global Warming Swindle