Table of contents |
2 Wall Street Journal 2001 3 IPCC Policymakers Summary criticism 4 Letter to his town mayor, 2003 5 Links |
National Academy of Sciences panel
Lindzen served on an 11-member panel [1] organized by the National Academy of Sciences. The panel's report, titled Climate Change Science: An Analysis of Some Key Questions[1], has been widely cited as evidence that leading scientists believe in global warming.
Indeed, the first paragraph of the report summary states,
"Greenhouse gases are accumulated in Earth's atmosphere as a result of human activities, causing surface air temperatures and subsurface ocean temperatures to rise. Temperatures are, in fact, rising. The changes observed over the last several decades are likely mostly due to human activities, but we cannot rule out that some significant part of these changes is also a reflection of natural variability."[1]
Wall Street Journal 2001
Subsequently, however, Lindzen wrote an article for the Wall Street Journal [1] (June 11, 2001), which insisted that "there is no consensus, unanimous or otherwise, about long-term climate trends or what causes them" and "we are not in a position to confidently attribute past climate change to carbon dioxide or to forecast what the climate will be in the future."
Indeed, he pointed out
"As usual, far too much public attention was paid to the hastily prepared summary rather than to the body of the report. The summary began with a zinger -- that greenhouse gases are accumulating in Earth's atmosphere as a result of human activities, causing surface air temperatures and subsurface ocean temperatures to rise, etc., before following with the necessary qualifications. For example, the full text noted that 20 years was too short a period for estimating long-term trends, but the summary forgot to mention this."
Lindzen worked on IPCC Working Group 1, Chapter 7, which is the section which considers the physical processes that are active in real world climate. Lindzen stated in May 2001 [1] that
the IPCC summary does not support the full document: see IPCC. Lindzen further criticized the IPCC for alterations to the Policymakers Summary of its 2001 global warming report, saying:
IPCC Policymakers Summary criticism
Editorial note: The "30 years" period begins at 1970, near the start of the warming trend. The IPCC Shanghai version's "50 years" period of "observed warming" begins in the midst of the 1945-1975 cooling period before the warming trend[1].
However, the NAS panel on which Lindzen served (see above) said [1]:
In September 2003 Lindzen wrote an open letter to his town mayor [1], putting his opinions on global warming. He says "...the temperature rise seen so far is much less (by a factor of 2-3) than models predict...". This statement is, however, false: see climate model.