LONDON, UK-An independent review of the latest United Nations report on climate change shows that the scientific evidence about global warming remains uncertain and provides no basis for alarmism.
In 2006, independent research organization The Fraser Institute convened a panel of 10 internationally-recognized experts to read the UN International Panel on Climate Change (IPCC) draft report and produce an Independent Summary for Policymakers. The result, released today and available at www.fraserinstitute.ca, is a detailed and thorough overview of the state of the science. This independent summary has been reviewed by more than 50 scientists around the world and their views on its balance and reliability are tabulated for readers.
"While a lot of effort goes into producing the large IPCC reports, its complex message is often obscured by its accompanying Summary for Policymakers. That summary report does not come from the scientific community. Instead it is developed through political negotiations by unnamed bureaucrats from various governments. Critics of past summaries point out they downplay and gloss over areas of uncertainty and data limitations," said Dr. Ross McKitrick, coordinator of the independent review and senior fellow with The Fraser Institute.
"The debate around climate change has become highly politicized and alarmist. So we asked a team of highly qualified scientists to look at the IPCC report and produce a summary that they felt communicates the real state of knowledge. Our intent with this document is to allow people to see for themselves what is known and what remains highly uncertain within climate change science."
The Fraser Institute's Independent Summary for Policymakers carefully connects summary paragraphs to the chapters and sections of the IPCC report from which they are drawn, allowing readers to refer directly to what is in the IPCC Report.
According to The Fraser Institute's independent summary of the IPCC report:
* Data collected by weather satellites since 1979 continue to exhibit little evidence of atmospheric warming, with estimated trends ranging from nearly zero to the low end of past IPCC forecasts. There is no significant warming in the tropical troposphere (the lowest portion of the Earth's atmosphere), which accounts for half the world's atmosphere, despite model predictions that warming should be amplified there.
* Temperature data collected at the surface exhibits an upward trend from 1900 to 1940, and again from 1979 to the present. Trends in the Southern Hemisphere are small compared to those in the Northern Hemisphere.
* There is no compelling evidence that dangerous or unprecedented changes are underway. Perceptions of increased extreme weather events are potentially due to increased reporting. There is too little data to reliably confirm these perceptions.
* There is no globally-consistent pattern in long-term precipitation trends, snow-covered area, or snow depth. Arctic sea ice thickness showed an abrupt loss prior to the 1990s, and the loss stopped shortly thereafter. There is insufficient data to conclude that there are any trends in Antarctic sea ice thickness.
* Current data suggest a global mean sea level rise of between two and three millimeters per year. Models project an increase of roughly 20 centimeters over the next 100 years, if accompanied by a warming of 2.0 to 4.5 degrees Celsius.
* Natural climatic variability is now believed to be substantially larger than previously estimated, as is the uncertainty associated with historical temperature reconstructions.
* Attributing an observed climate change to a specific cause like greenhouse gas emissions is not formally possible, and therefore relies on computer model simulations. These attribution studies do not take into account the basic uncertainty about climate models, or all potentially important influences like aerosols, solar activity, and land use changes.
* Computer models project a range of future forecasts, which are inherently uncertain for the coming century, especially at the regional level. It is not possible to say which, if any, of today's climate models are reliable for climate prediction and forecasting.
"There is no evidence provided by the IPCC report that the uncertainty around climate change can be formally resolved from first principles, statistical hypothesis testing or modeling exercises," McKitrick said.
"What does this mean for the average person? It means that while scientific evidence shows the climate is naturally variable, we still don't know the extent to which humans are contributing to future climate change and whether or not such change is a good or bad thing. People who are bewildered by the intense global warming alarmism of the past few years should read the Independent Summary for Policymakers to get a more accurate and balanced understanding of the real state of knowledge on this important subject."
Click here to view or print the complete independent summary. (PDF file)
Department of Economics, University of Guelph
Tel: 001-519-824-4120 ext 52532
Email: Ross McKitrick.
Nicholas Schneider, Policy Analyst, The Fraser Institute Centre for Risk, Regulation & the Environment
Tel: 001-416-363-6575 ext: 222
Email: Nicholas Schneider.
The Fraser Institute is an independent research and educational organization based in Canada. Its mission is to measure, study, and communicate the impact of competitive markets and government intervention on the welfare of individuals. To protect the Institute's independence, it does not accept grants from governments or contracts for research. Visit www.fraserinstitute.ca.
For further information, contact:
Dean Pelkey, Associate Director of Communications, The Fraser Institute,
Email: Dean Pelkey.