Yesterday I posted a blog titled
To his credit, despite my criticism, Andy presented a rebuttal by Michael Schlesinger on his website. I have reposted Michael’s response below in its entirety, and then I follow with my comment.
POST FROM DOT EARTH
Roger Pielke, Sr., of Colorado State strongly criticized Michael Schlesinger’s assessment of the temperature data — http://wattsupwiththat.com… and Dr. Schlesinger sent this reply:
I have been expecting this comment, not from anyone in particular, but from someone – and here it is. Of course we have only one raw dataset comprised of all the world’s surface temperature measurements.
How could it be otherwise?
The different groups that have analyzed this single raw dataset have made different decisions in their analyses. For example, whether the station data should be averaged as is, or whether they should first be area-weighted for the region of their coverage.
It is because of the differences in analysis methods that the results of the 4 groups are not identical.
That is healthy.
So, one set of raw temperature data, of needs be, and several different decisions about how to analyze these raw data, all lead to the same conclusion – the Earth’s near-surface temperature has warmed by about 0.9°C (1.6°F) during the past 150 years.
The case of detecting climate change is closed, period, RPS or any other climate skeptic notwithstanding.
The next task is to attribute these detected changes in near-surface temperature to their causes, natural or not – us (and U.S.).
This can be done only with a climate model, either the simple one that I and Natasha Andronova applied in our year-2000 paper, referenced in my cotribution to Andy Revkin’s blog today, or with climate science’s most comprehensive climate models, our coupled atmosphere-ocean general circulation models.
As documented in the IPCC AR4, it is not possible to replicate the observed warming due to natural causes – the sun and volcanoes – alone. Such replication can be done only by including the effects of the human-generated increase in the concentrations of greenhouse gases.
Thus the case of the causes of the observed climate change is closed, period – RPS or any other climate skeptic notwithstanding.
What remains is to decide what to do about this, bury our collective heads in the sand and pretend that reality is otherwise, or take on the hard task before us of making the transition this century from the fossil-fuel age to the post fossil-fuel age.
As I am an engineer as well as a scientist, I challenge humanity to this great and singular task.
I will not be here much longer, so I can at most see only the beginning of this voyage.
But my 3 children and 6 grandchildren will be here to see whether or not we now behave in a responsible way to them and their progeny, and to our one-and-only planet.
To not do so would be to condemn billions of human beings, now and in the future, to death by climate.
THIS WE MUST NOT DO!
First, I am pleased that Michael Schlesinger has confirmed what I have reported; in that
“…we have only one raw dataset comprised of all the world’s surface temperature measurements.”
However, what this means is that the 0.9°C increase in the global average surface temperature during the last 150 years is guaranteed to be closely replicated by each of the research centers that are analyzing the data. This close agreement was reported on in the CCSP 1.1 report as I reproduced in my post
An excerpt from the CCSP 1.1. report, as I reproduced in my post, reads
“While there are fundamental differences in the methodology used to create the surface data sets, the differing techniques with the same data produce almost the same results (Vose et al., 2005a).”
Michael introduces another broader issue, however, in his statement
“The case of detecting climate change is closed, period, RPS or any other climate skeptic notwithstanding.”
This statement is a further example of the narrow and closed viewpoint illustrated in the released CRU e-mails. I agree with Michael that we have detected human climate forcing effects. To label me as a skeptic, however, is completely wrong (as Andy knows; e.g. see and see)
More importantly, I am disappointed in his failure to discuss the fundamental scientific issue that remains which is which of the two hypotheses below are correct:
Hypothesis 2b was rejected in our joint paper (of which all of the authors are AGU Fellows)
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. An edited version of this paper was published by AGU. Copyright (2009) American Geophysical Union
Michael Schlesinger clearly accepts Hypothesis 2b. I invite him to discuss why he rejects Hypothesis 2a, since only one of these hypotheses can be correct.