Rahmstorf’s Claims Of Increasing Extreme Weather–A Damning Put Down By NOAA Expert
By Paul Homewood
Rahmstorf and Coumou recently published their paper “A Decade of Weather Extremes”, which repeats the oft made claim that “extreme weather” is on the increase.
However, Martin Hoerling, leader of the climate extremes attribution team at NOAA, has replied with a pretty damning assessment.
A few quick comments from my (single) read through.
- Not a scientific paper, but more Op-Ed. If the science of extremes is desired, then the best current synthesis is IPCC SREX, 2012. [This is the Intergorvernmental Panel on Climate Change report, "Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation," which I wrote about here.]
- Exaggerated language, and many unsubstantiated assertions. For instance, in what manner did the last decade experience an “unprecedented” number of extreme weather events? Note that the increase in heat waves was largely balanced by a decrease in cold waves—-
- Overly simplistic view of the relation between damage, human suffering, and the extremes. Much more balanced arguments can be found in R. Pielke Jr.’s work that consider changes in society, communities, coastal development, etc. Also, a more useful perspective is found in the recent EOS article by Mike Wallace, titled “Weather and Climate Extreme Events: Teachable Moments.”
- Very few of the [cases of extreme weather listed in the paper] have undergone a scientific investigation of contributing factors, let alone human impacts. I believe that a read of the Lewis and Clark journals would reveal an impressive list of extreme weather also…. so what is one to make of this list for the 2001-2011 period provided in this Perspective by Coumou and Rahmstorf. The fact is that extremes happen, have happened, and will continue to happen. For some, their character, preferred phase, and intensity may be changing (aside from temperature extremes, the detection and attribution evidence to date is weak).
- I suspect that if one engaged in grand mitigation today (as useful as that would be for many other purposes), many of the extremes listed in [the paper] would happen anyway, and will likely happen again.
- The piece lacks all perspective on the human and technological elements contributing to greater observational capacity to sense extremes (radar, satellite), nor does it consider the reality of a heighten interest by the public in extremes, given recent public discourses.
- The matter of attribution, as raised in the second to last paragraph, is a much broader science that merely determining the change in probability due to greenhouse-gas forcing….which is an inherently difficult and uncertain undertaking. The piece ignores the broader context in which all manner of contributing factors is assessed to understand the magnitude of events, their temporal and regional specificity (e.g., why did the heat wave happen over Texas (rather than Washington), why did it occur in 2011 (and not 2009, or next year), and why did it break the previous records by a factor of 2. After all, the irony of extreme events is that the larger the magnitude the smaller the fractional contribution by human climate change.
- Consistent with the policy-direct tone of this piece, hyperbole is used throughout. The piece often convoluting apparent “effects” of apparent changes in extremes in the last decade with causes not to arise till the latter part of the 21st century.
If anybody still believes our recent climate has become more extreme, they should study a bit more history. Perhaps they should start with 1971 and this list of extreme weather.