The 2001 U.S. Climate Action Report (USCAR) is, in general, more balanced than analogous compendia, such as the Third Assessment Report of climate change recently published by the United Nations Intergovernmental Panel on Climate Change (IPCC) , or the U.S. National Assessment (USNA) of climate change.
However, certain portions of USCAR, particularly Chapter 6, rely heavily on the USNA or the 2001 report of the National Academy of Sciences (which itself relies heavily on the USNA). Whatever originates from the USNA is highly flawed because the USNA is based upon a true miscarriage of science: it is based upon two models for future projections of climate that perform worse than a table of random numbers when applied to recent climate. The producers of the USNA, mainly the U.S. Global Change Research Program, have ignored this glaring problem, even as it is well‐known that they were aware of it. Further, the USNA is based upon a selection of the two most extreme climate models for U.S. temperature and precipitation, for which there is no scientific defense.
Consequently the quality of large sections of the USCAR has been fatally impaired by the acceptance of the nonscientific USNA. This applies mainly to Chapter 6, “Impacts and Adaptation.” These sections — and mainly Chapter 6 — need either to be re‐written, or a prominent note needs to be appended detailing the tragic flaws in the USNA.
It is hoped that these comments will force a re‐opening of the USNA process, which was headed by the U.S. Global Change Research Program (USGCRP) with a specific investigation into how such a document could have been published, when USGCRP and the associated scientists knew that it was based upon models that simply did not work. As it stands, it is the blackest of marks upon U.S. Environmental Science in recent decades, and the historical credibility of our considerable efforts in this science are at stake. The blatant disregard of science in the USNA (and therefore in the USCAR) will not be noted today or next week. But, in coming decades, academic research carried out in a more dispassionate atmosphere than exists today will surely uncover these flaws and the attempts to cover them up. A responsible Agency would expose them NOW. This review affords that opportunity.
My main comments are directed at Chapter 6; however, there are a few others included below.