Heat around urban areas is one issue, and some of the debate is focused on tempterature readings. CO2 around urban areas is another issue, and certainly, if the only readings were taken around urban areas where the population number of drivers was growing, say, then the heat and CO2 put off by such urban centers might be expected to increase.

But what if the tempterature readings were not all taken from urban areas? How many sites were urban?

What if the population growth in an urban area was negligible, and other factors had to be taken into consideration, such as people insullating their homes or using more fuel-efficient cars, etc?

So the proof is in the details.

As far as I understand it, these urban readings have nothing to do with the data from polar ice core samples that show rising levels of CO2.

As you know, Antarctica is not yet an urban center.

And the criticism about possible flaws in the data from urban centers does nothing to invalidate the observations that many glaciers have been melting, permafrost has been lost in Alaska and other northern regions; Lake Victoria is drying up; the water habitat and fish population/compostion of Lake Superior has been changing because of rising water temperatures; and we’ve had some of the hottest summers on record all in the last 10 years.

So yes, those are good questions for scientists to ask so that they’re certain about the reliability of the data, but no, in the end I think you’ll find that most scientists believe that even if the Mann graph is somewhat flawed (no graph can be perfect), global warming is still a very serious problem.

Two Canadian researchers subsequently requested the data used to develop the graph and discovered that Mann had failed to account for the effects of Urban heat sinks. This rendered the graph almost meaningless. The IPCC, in its 4th assessment, makes no mention of the graph, since it was discredited. Am I wrong about this?

Dear Senator Neuville -

I get the feeling from your blog that you don’t feel that global warming is a reality that faces the human race. Please make sure that when you do your research that the science you read about is “peer reviewed science”.

The most important peer reviewed document is the IPCC report here: http://www.ipcc.ch/ (direct link here: http://www.ipcc.ch/SPM2feb07.pdf)
Findings of the IPCC Fourth Assessment Report: Climate Change Science (for the more layman person - like myself) - http://www.ucsusa.org/global_warming/science/ipcc-highlights1.html
What is the IPCC? : http://environmentaldefenseblogs.org/climate411/2007/02/05/what-is-the-ipcc-anyway/
What is peer reviewed science and why is it important?: http://www.ncdc.noaa.gov/paleo/globalwarming/peerreview.html
There is a lot of PR pollution that is clouding the science on climate change. As you do your research please be sure to follow any money trails from the “skeptics” and make sure that their interests are not compromised by special interest groups.

Richard Lindzen - http://www.exxonsecrets.org/html/personfactsheet.php?id=17

Dr. Lindzen was a member of the UN’s Intergovernmental Panel on Climate Change and contributed to the Second Assessment Report. He regularly takes issue with the general conclusions drawn from the IPCC’s reports. His prolific writings assert that climate change science is inconclusive, and he has testified multiple times before Congress.

Ross Gelbspan reported in 1995 that Lindzen “charges oil and coal interests $2,500 a day for his consulting services; his 1991 trip to testify before a Senate committee was paid for by Western Fuels, and a speech he wrote, entitled ‘Global Warming: the Origin and Nature of Alleged Scientific Consensus,’ was underwritten by OPEC.” (”The Heat is On: The warming of the world’s climate sparks a blaze of denial,” Harper’s magazine, December 1995.) Lindzen signed the 1995 Leipzig Declaration

I will absolutely agree that there are some people whose minds have been changed that aren’t compromised. Dr. Claude Allegre appears to be one of them. However, if you dig carefully into the peer reviewed science (of which the IPCC report is) I think that the vast majority (> than 90%) are in agreement.

Another website: http://www.realclimate.org/ - RealClimate is a commentary site on climate science by working climate scientists for the interested public and journalists. We aim to provide a quick response to developing stories and provide the context sometimes missing in mainstream commentary. The discussion here is restricted to scientific topics and will not get involved in any political or economic implications of the science

Thanks for your time.

Tim Reckmeyer