After citing a couple of Cornwall Alliance’s articles in discussion, an educator friend got this response from one of his former students:

The problem with referencing the Cornwall Alliance to discredit statistics from the NASA Goddard Institute for Space Studies is that one (the Cornwall Alliance) is a political advocacy organization with no scientific relevance while the other (NASA) has the weight of objective fact and science behind it. To me there is virtually no legitimate way one can counter the statistical evidence of the earth’s atmospheric temperature increasing at an accelerating rate. I know many don’t want to believe it, but the facts are indeed the facts in this case. The only thing I think it’s legitimate to argue objectively about is WHY the temperature is warming, not WHETHER it is warming globally.

It’s kind of humorous, really.

First, the data on which we rely for the fact that there was no statistically significant increase in global average temperature from early 1997 through late 2015 (nearly 18 years) are NASA data! They’re obtained by satellite observation run by Dr. Roy W. Spencer (a Senior Fellow of the Cornwall Alliance, Principal Research Scientist in Climatology at the University of Arkansas-Huntsville, and U.S. Science Team Leader on NASA’s Aqua Satellite remote sensing program) and Dr. John Christy (also Principal Research Scientist in Climatology at the University of Arkansas-Huntsville), both of whom won “NASA’s Exceptional Scientific Achievement Medal for their global temperature monitoring work with satellites.” The most recent update of those data so far published is at http://www.drroyspencer.com/2016/09/uah-global-temperature-update-for-august-2016-0-44-deg-c/, and, as usual, “The ‘official’ UAH global image for August, 2016 should be available in the next several days here.” Those data show the absence of warming over that period quite clearly, and, ipso facto, they show the falsehood of the former student’s claim that “earth’s atmospheric temperature [is] increasing at an accelerating rate.” The significant upward trend in the period of the satellite data (which started in 1979) all occurred from 1979–1997; since then, unless one improperly counts the first 5 months of 2016 (whose unusual warmth was, like that of 1998, driven by an unusually strong El Niño), there has been a near-zero trend. (Note that I didn’t say the warming trend was from 1979–1998, for to do so would be to make the same mistake as to claim a warming trend based on the El Niño-driven 2016 warming.)

Second, on climate change and climate and energy policy, NASA GISS has functioned heavily as a political advocacy organization for at least the last twenty years under the leadership of recently retired Dr. James Hansen, one of the most outspoken, and exaggeration-prone, climate alarmists, and continues to do so under his replacement, Gavin Schmidt, another long-time outspoken climate alarmist. By his own criterion, then, the former student shouldn’t trust GISS either.

Third, appeals to authority and ad hominem are unscientific and most certainly can’t trump appeals to empirical evidence.

Fourth, even if we accept NASA GISS’s estimate (based on a variety of land- and sea-based thermometers and proxies) of total increase of GAT from 1850 (or 1880—different NASA documents have cited different starting points) to the present of ~1.0˚C, that yields a decadal warming rate of ~0.059˚C (or 0.071˚C), which is ~1/4 (or ~1/3) the rate of warming in response solely to rising CO2 concentration predicted by the average of the 102 CMIP-5 climate models on which the UN IPCC (along with various national bodies) relies for its estimate of CO2’s warming effect.

Further, that actually underestimates the divergence of the models’ predictions from real-world observations, because about ¼ to ½ of that warming, according to GISS, occurred before 1960, i.e., before CO2 concentration rose enough to contribute significantly to the warming, and because one cannot rule out the possibility that some (maybe even all) of the post-1960 warming was naturally rather than anthropogenically driven.

The former student should go to the trouble of actually reading one of our major papers on the subject (e.g., this), done by bona fide experts in the field, and considering the evidence and arguments in it, rather than simply bowing unscientifically (and unchristianly—1 Thessalonians 5:21) to GISS (or anyone else, including us) as an authority.