Arguments
Do 500 scientists refute the consensus?
The skeptic argument...
500 scientists refute the consensus
"According to a report in the WorldNet Daily, more than 500 scientists have published evidence refuting the current man-made global warming scare, according to a new analysis of peer-reviewed literature by the Hudson Institute." (American Conservative Daily)
What the science says...
The latest attack on global warming consensus comes from Dennis Avery and Fred Singer who claim to have found 500 peer reviewed papers refuting that the last few decades of global warming are primarily anthropogenic. Previous attempts to find peer reviewed skeptic studies tend to miscategorise as skeptic despite the intent of the author or indeed the content of the paper. Avery and Singer appear to carry on this tradition.
While their press release peddles many skeptic myths, the major recurring theme is that over 300 studies have found climate has changed in the past and/or that the sun is connected. Tamino at Open Mind does a good job explaining the 1500 year natural cycles (or Dansgaard-Oeschger events) along with some useful links to relevant peer reviewed studies. I've also touched on the notion that climate has changed naturally in the past so it must be natural now.
Regarding the sun's connection to global warming (or lack thereof), there is much empirical data and many studies on the topic that have concluded the sun's contribution to global warming has been minimal. Nevertheless, blaming climate change on the sun is intuitive - to paraphrase the Great Global Warming Swindle: "human small... sun big". Hard to refute that kind of barnstorming logic. Nevertheless, I'll have another crack at breaking down the logical steps of why we know solar variations aren't causing global warming:
- The sun has closely correlated with temperature in the past and been a major driver of climate
- The correlation ended in the 70's when the modern global warming trend began
- Therefore the sun cannot be the driving force of global warming over the past few decades
Figure 1: Annual global temperature change (thin light red) with 11 year moving average of temperature (thick dark red). Temperature from NASA GISS. Annual Total Solar Irradiance (thin light blue) with 11 year moving average of TSI (thick dark blue). TSI from 1880 to 1978 from Solanki. TSI from 1979 to 2009 from PMOD.
In other words, all the studies showing past correlation between solar activity and temperature only serve to emphasise the fact that the correlation no longer exists. Rather than refute the consensus, they reinforce it.
Last updated on 9 July 2010 by John Cook.
On the "Listing of Arguments" page, the "What the Science" says blurb for this argument is:
"Around 97% of climate experts agree that humans are causing global warming."
This statement does not appear in the above rebuttal article.
"More than 1000 dissenting scientists (updates previous 700 scientist report) from around the globe have now challenged man-made global warming claims made by the United Nations Intergovernmental Panel on Climate Change (IPCC) and former Vice President Al Gore. This new 2010 320-page Climate Depot Special Report — updated from 2007′s groundbreaking U.S. Senate Report of over 400 scientists who voiced skepticism about the so-called global warming “consensus” — features the skeptical voices of over 1000 international scientists, including many current and former UN IPCC scientists, who have now turned against the UN IPCC. This updated 2010 report includes a dramatic increase of over 300 additional (and growing) scientists and climate researchers since the last update in March 2009. This report’s release coincides with the 2010 UN global warming summit being held in Cancun."
Why the initial use of "dissenting" when the substance of the sentence is to establish dissent? Upon what is this dissent focused? Note that Watts probably includes Pielke in this list, but Pielke accepts AGW; he just differs from other scientists on the contribution of various components. How many other of the "dissenting scientists" are in the same position? How many reject the idea that atmospheric CO2 absorbs and emits at certain wavelengths? How many simply reject some of Al Gore's implied but not directly stated consequences? (I believe I read Gavin Schmidt disagreeing with something in the Gore documentary; if so, add him to the list) All WUWT is effectively doing is establishing doubt--not establishing an alternative position, not establishing scientific progress. How many of the scientists in the Senate report agree on the same physical model? Who are these scientists, and what weight should they carry for people who pay attention to survey results? Show me the specific reasons for dissent, and I'll show you why the 500, 700, 1000, whatever list is meaningless.
A better question is "what does the list mean to you?" (or to anyone who encounters such things)
where can I find a list of these climate experts?
what are the criteria for determining a climate expert?