First, as posted on my son’s weblog in
the global temperature anomaly is essentially irrelevant in terms of climate change issues that matter to society and the environment. Even in terms of global warming, it is a grossly inadequate measure, as discussed, for example, in
Pielke Sr., R.A., 2003: Heat storage within the Earth system. Bull. Amer. Meteor. Soc., 84, 331-335.
Pielke Sr., R.A., 2008: A broader view of the role of humans in the climate system. Physics Today, 61, Vol. 11, 54-55.
The global average surface temperature, however, unfortunately, has become the icon of the IPCC community and in the policy debate. As my son wrote in his post
“The debate over climate change has many people on both sides of the issue wrapped up in discussing global average temperature trends. I understand this as it is an icon with great political symbolism. It has proved a convenient political battleground, but the reality is that it should matter little to the policy case for decarbonization.”
This political focus has resulted in Richard Muller’s testimony on his Berkeley Earth Surface Temperature project yesterday to The Science, Space and Technology Committee of the House Of Representatives. In his (in my view, premature) testimony he makes the following claims
“The world temperature data has sufficient integrity to be used to determine global temperature trends”
“…. we find that the warming seen in the “poor” stations is virtually indistinguishable from that seen in the “good” stations.”
“The Berkeley Earth agreement with the prior analysis surprised us, since our preliminary results don’t yet address many of the known biases”?
The contradictory statement in the last sentence from his testimony contradicts the first two sentences.
All his study has accomplished so far is to confirm that NCDC, GISS and CRU honestly used the raw observed data as the starting point for their analyses. This is not a surprising result. We have never questioned this aspect of their analyses.
The uncertainties and systematic biases that we have published in several peer-reviewed papers, however, remain unexplored so far by Richard Muller and colleagues as part of The Berkeley Earth Surface Temperature project. We summarized these issues in our paper
Pielke Sr., R.A., C. Davey, D. Niyogi, S. Fall, J. Steinweg-Woods, K. Hubbard, X. Lin, M. Cai, Y.-K. Lim, H. Li, J. Nielsen-Gammon, K. Gallo, R. Hale, R. Mahmood, S. Foster, R.T. McNider, and P. Blanken, 2007: Unresolved issues with the assessment of multi-decadal global land surface temperature trends. J. Geophys. Res., 112, D24S08, doi:10.1029/2006JD008229
where the issues include:
- a systematic bias in the use of multi-decadal trends in minimum air temperatures
- the use of surface observing sites that are not spatially representative of the region
- the failure to consider the variation of surface air temperature trends with height above the surface
- the lack of incorporation of the effect of concurrent multi-decadal trends in the surface air absolute humidity
- the absence of the statistical documentation of the uncertainty of each step in the adjustment of raw data to a “homogenized data set” (e.g. time of observation bias; equipment changes; station moves)
- the need to assess the absolute temperatures at which a temperature trend occurs, since a temperature anomaly at a cold temperature has less of an effect on outgoing long wave radiation than the same temperature anomaly at a warmer temperature.
We have explored most of these issues in peer-reviewed papers and found them to be important remaining uncertainties and biases. Richard Muller and his colleagues have not yet examined these concerns, yet chose to report on his very preliminary results at a House Hearing. A sample of our papers include:
Fall, S., N. Diffenbaugh, D. Niyogi, R.A. Pielke Sr., and G. Rochon, 2010: Temperature and equivalent temperature over the United States (1979 – 2005). Int. J. Climatol., DOI: 10.1002/joc.2094
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., 114, D21102, doi:10.1029/2009JD011841
Montandon, L.M., S. Fall, R.A. Pielke Sr., and D. Niyogi, 2011: Distribution of landscape types in the Global Historical Climatology Network. Earth Interactions, 15:6, doi: 10.1175/2010EI371
Steeneveld, G.J., A.A.M. Holtslag, R.T. McNider, and R.A Pielke Sr, 2011: Screen level temperature increase due to higher atmospheric carbon dioxide in calm and windy nights revisited. J. Geophys. Res., 116, D02122, doi:10.1029/2010JD014612.
Richard Muller should be examining the robustness of our conclusions, as part of his project.
Richard does appropriately acknowledges Anthony’s and Steve McIntyre’s contribution in his testimony where he writes
“Without the efforts of Anthony Watts and his team, we would have only a series of anecdotal images of poor temperature stations, and we would not be able to evaluate the integrity of the data. This is a case in which scientists receiving no government funding did work crucial to understanding climate change. Similarly for the work done by Steve McIntyre. Their “amateur” science is not amateur in quality; it is true science, conducted with integrity and high standards.”
This is well deserved recognition for both research colleagues. One does not need a “Ph.d.” by your name, to do world-class research!
Anthony Watts has prepared an excellent response to Richard Muller’s presentation in
His insightful dissection of the problems with Richard Muller’s presentation and of NCDC’s inappropriate behavior (which I completely agree with) include the statements that
“NOAA’s NCDC created a new hi-tech surface monitoring network in 2002, the Climate Reference Network, with a strict emphasis on ensuring high quality siting. If siting does not matter to the data, and the data is adequate, why have this new network at all?”
“Recently, while resurveying stations that I previously surveyed in Oklahoma, I discovered that NOAA has been quietly removing the temperature sensors from many of the USHCN stations we cited as the worst (CRN4, 5) offenders of siting quality. For example, here are before and after photographs of the USHCN temperature station in Ardmore, OK, within a few feet of the traffic intersection at City Hall.”
“Expanding the search my team discovered many more instances nationwide, where USHCN stations with poor siting that were identified by the surfacestations.org survey have either had their temperature sensor removed, closed, or moved. This includes the Tucson USHCN station in the parking lot, as evidenced by NOAA/NCDC’s own metadata online database….”
He concludes with
“It is our contention that many fully unaccounted for biases remain in the surface temperature record, that the resultant uncertainty is large, and systemic biases remain. This uncertainty and the systematic biases needs to be addressed not only nationally, but worldwide. Dr. Richard Muller has not yet examined these issues.”
I completely agree with Anthony’s submission to the House committee in response to Richard Muller’s testimony. Richard Muller has an important new approach to analyze the surface temperature data. We hope he adopts a more robust and appropriate venue to present his results.