The Issue That James Annan and Gavin Schmidt Should Focus On With Respect To The Klotzbach Et Al 2009 Paper

There has been quite a bit of discussion by James Annan (see and see) and Gavin Schmidt (see) on our paper

Klotzbach, P.J., R.A. Pielke Sr., R.A. Pielke Jr., J.R. Christy, and R.T. McNider, 2009: An alternative explanation for differential temperature trends at the surface and in the lower troposphere. J. Geophys. Res., in press.

 which is quite peripheral to the conclusions of our paper.  In our multi-authored paper

Mahmood, R., R.A. Pielke Sr., K.G. Hubbard, D. Niyogi, G. Bonan, P. Lawrence, B. Baker, R. McNider, C. McAlpine, A. Etter, S. Gameda, B. Qian, A. Carleton, A. Beltran-Przekurat, T. Chase, A.I. Quintanar, J.O. Adegoke, S. Vezhapparambu, G. Conner, S. Asefi, E. Sertel, D.R. Legates, Y. Wu, R. Hale, O.W. Frauenfeld, A. Watts, M. Shepherd, C. Mitra, V.G. Anantharaj, S. Fall,R. Lund, A. Nordfelt, P. Blanken, J. Du, H.-I. Chang, R. Leeper, U.S. Nair, S. Dobler, R. Deo, and J. Syktus, 2009: Impacts of land use land cover change on climate and future research priorities. Bull. Amer. Meteor. Soc., in press

We summarized the issue as follows

“The stable nocturnal boundary layer does not measure the heat content in a large part of the atmosphere where the greenhouse signal should be the largest (Lin et al. 2007; Pielke et al. 2007a). Because of nonlinearities in some parameters of the stable boundary layer (McNider et al. 1995), minimum temperature is highly sensitive to slight changes in cloud cover, greenhouse gases, and other radiative forcings. However, this sensitivity is reflective of a change in the turbulent state of the atmosphere and a redistribution of heat not a change in the heat content of the atmosphere (Walters et al. 2007). Using the Lin et al. (2007) observational results, a conservative estimate of the warm bias resulting from measuring the temperature from a single level near the ground is around 0.21°C per decade (with the nighttime minimum temperature contributing a large part of this bias). Since land covers about 29% of the Earth.s surface, extrapolating this warm bias could explain about 30% of the IPCC estimate of global warming. In other words, consideration of the bias in temperature could reduce the IPCC trend to about 0.14°C per decade; still a warming, but not as large as indicated by the IPCC.”

So far, it appears that neither James or Gavin are particularly knowledegable on boundary layer physics.  While they certainly have expertise in other areas in climate science, they have failed so far to comment on the topic in the above paragraph (which is what the Klotzbach et al (2009), Lin et al (2007) and Pielke and Matsui (2005) papers are about.

My current weblog is an invitation to them to comment on the above paragraph (either as guest weblogs or on their sites). If they ignore this request, it would further demonstrate that they are commenting outside of their expertise on the subject of our papers, and that their real goal is simply to malign papers they disagree with.

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