In an earlier post I mentioned that I was going to undertake to read a lot more this year. Such is still my intention.
Unfortunately, my first self-imposed assignment was the recently released draft of the National Climate Assessment Development Advisory Committee’s Climate Assessment Report.
So far I have read only their prefatory Letter to the American People, found here. There are elements of this letter that I believe to be scare talk not founded in fact. In fact, some of it seems hyperbole written with the intent to frighten the American people rather than inform them.
Their opening sentence qualifies in that regard: (2) “Climate change, once considered an issue for a distant future, has moved firmly into the present.”
Contrast that with the statement from the Intergovernmental Panel on Climate Change’s SREX, or special report, issued in March of 2012: “There is… high agreement that long-term trends in normalized losses (due to extreme weather) have not been attributed to natural or anthropogenic climate change.” Later in the report we read, “…droughts have become less frequent, less intense, or shorter, for example, in central North America and northwestern Australia,” and “There is limited to medium evidence available to assess climate-driven observed changes in the magnitude and frequency of floods at regional scales because the available instrumental records of floods at gauge stations are limited in space and time, and because of confounding effects of changes in land use and engineering. Furthermore, there is low agreement in this evidence, and thus overall low confidence at the global scale regarding even the sign of these changes.”
The IPCC also writes “Increasing exposure of people and economic assets has been the major cause of long-term increases in economic losses from weather- and climate-related disasters (high confidence). Long-term trends in economic disaster losses adjusted for wealth and population increases have not been attributed to climate change, but a role for climate change has not been excluded.”
The Letter to the American People continues: “(11) Americans are noticing changes all around them. Summers are longer and hotter, and periods of (12) extreme heat last longer than any living American has ever experienced.”
This is not true. There are over 6 million Americans alive today who experienced summers as long and hot, with great periods of extreme heat in the mid-1930s, when the Palmer Drought Index was the same as current periods, and tens of millions more who saw the mid-70s, when drought conditions were almost as high. Drought is a cyclical event that is experienced throughout large sections of the United States and has done so since pre-historical times.
If the National Climate Assessment and Development Advisory Committee is going to trumpet false but frightening findings to the American People in the introduction to its report, what will the rest show us?
Roger Pielke Jr. has made a start in cataloguing their errors in his area of specialization. You can read about it here.
More importantly for me, if I find glaring and obvious mistakes in the very beginning of their report, is it worth my time to plough through the rest of it?