Pielke Sr. on Stratospheric Water Vapor
Posted by Jeff Id on February 15, 2010
Roger Pielke Sr. has an interesting commentary on the recent paper on stratospheric water vapor. The paper seemed important when it came out and apparenlty isn’t getting enough attention. Dr. Pielke has comments turned off but he has a bunch of links to his commentary. I’ve copied the post in full because he has comments off on his blog and there are several links to other sections of his site.
Comments On “Contributions Of Stratospheric Water Vapor To Decadal Changes In The Rate Of Global Warming By Solomon Et Al 2010
Susan Solomon, Karen Rosenlof, Robert Portmann, John Daniel, Sean Davis, Todd Sanford, Gian-Kasper Plattner, 2010: Contributions of Stratospheric Water Vapor to Decadal Changes in the Rate of
Global Warming. http://www.sciencexpress.org / 28 January 2010 / Page 1 / 10.1126/science.1182488 ( see also)
has already received considerable attention on blogs (e.g. see). [thanks to Marcel Crok for first alerting me to the paper].
The abstract of this paper reads
“Stratospheric water vapor concentrations decreased by about 10% after the year 2000. Here we show that this acted to slow the rate of increase in global surface temperature over 2000-2009 by about 25% compared to that which would have occurred due only to carbon dioxide and other greenhouse gases. More limited data suggest that stratospheric water vapor probably increased between 1980 and 2000, which would have enhanced the decadal rate of surface warming during the 1990s by about 30% compared to estimates neglecting this change. These findings show that stratospheric water vapor represents an important driver of decadal global surface climate change.”
I have two comments on the implications of this paper:
1. This study reinforces that climate variability and change is more complex than just a response to added CO2 and a few other human greenhouse gases. This conclusion has been emphasized in a variety of publications; e.g.
National Research Council, 2005: Radiative forcing of climate change: Expanding the concept and addressing uncertainties. Committee on Radiative Forcing Effects on Climate Change, Climate Research Committee, Board on Atmospheric Sciences and Climate, Division on Earth and Life Studies, The National Academies Press, Washington, D.C., 208 pp.
Pielke Sr., R., K. Beven, G. Brasseur, J. Calvert, M. Chahine, R. Dickerson, D. Entekhabi, E. Foufoula-Georgiou, H. Gupta, V. Gupta, W. Krajewski, E. Philip Krider, W. K.M. Lau, J. McDonnell, W. Rossow, J. Schaake, J. Smith, S. Sorooshian, and E. Wood, 2009: Climate change: The need to consider human forcings besides greenhouse gases. Eos, Vol. 90, No. 45, 10 November 2009, 413
2. The evidence that the stratospheric temperatures have not been behaving as the IPCC models have predicted (i.e. with a more-or-less monotonic cooling in the absence of major volcanic eruptions of ash into the stratosphere) has been clear to anyone who has looked at the data.
I discussed this lack of cooling in my post
Is there Continued Stratosphere Cooling? [from March 13, 2006]. The most recent lower stratospheric data can be seen in the figure below from RSS MSU data (see Figure 7 where since about 1995 the trend has been about flat).
The reason for the lack of a multi-year trend in the lower stratosphere since 1995 has not received the attention it needs. Indeed, since the IPCC multi-decadal global climate models have not predicted this behavior, this is yet another reason to question the skill of their forecasts of climate for the coming decades.