Examining Dr. John Christy's Global Warming Skepticism
Posted on 12 June 2011 by dana1981
By far the three most prominent and most frequently referenced climate scientists who are "skeptical" of the dangers of human-caused global warming are Dr. Richard Lindzen of MIT, and Drs. Roy Spencer and John Christy of the University of Alabama at Huntsville (UAH). These are not your typical unqualified "skeptics", like so many others (i.e. computer programmers, politicians, and former political consultants). No, these are genuine climate scientists who receive government research grants, publish peer-reviewed studies, and have not received any funding from fossil fuel companies in recent years. Thus their arguments are well worth examining. Is there scientific validity to their skepticism?
This question is of particular importance since they have recently received so much media attention. Dr. John Christy, for example, has recently testified before U.S. Congress, appeared on an Australian radio talk show, and on a Canadian radio show. In these appearances, he advised his audiences that there is a great deal of uncertainty regarding man-made global warming, and that we need not take significant steps to reduce human greenhouse gas emissions. This advice directly contradicts the findings of the vast majority of Dr. Christy's peers, most recently by the Australian Climate Commission, which concluded that we know beyond a reasonable doubt that humans are the primary cause of the current global warming, and it is critical that we immediately implement policies to reduce global greenhouse gas emissions.
We recently examined the scientific arguments of Dr. Richard Lindzen, and found that his arguments do present a mostly consistent alternative to the man-made global warming theory. Essentially Dr. Lindzen argues that the climate is not very sensitive to increases in atmospheric greenhouse gases, and the warming we've observed is mainly due to the internal variability of the climate system. However, we also found that Dr. Lindzen's alternative hypothesis is little more than a flimsy house of cards, with each scientifically faulty argument built upon several other faulty arguments. In fact every single one of his arguments has turned out to be inconsistent with the observational evidence. So what about Dr. Christy - does he present a consistent alternative hypothesis to the man-made global warming theory which is more scientifically accurate than Dr. Lindzen's?
No, as it turns out, we find that Dr. Christy's arguments create a similar, but less sophisticated alternative in comparison to Dr. Lindzen's. The foundation of Dr. Christy's arguments is that despite over four decades of climate science research, we still do not understand the workings of the global climate much better than we did in 1970, and that as a result, we are "jumping to conclusions" in blaming recent global warming on human activities. However, contrary to Dr. Christy's uncertainty exaggerations, the human influence on the recent global warming is one of the aspects which climate scientists are most certain about.
However, once he sows the seeds of doubt into the minds of his audience, Dr. Christy proceeds to argue, similar to Dr. Lindzen, that recent warming could simply be due to the internal variability of the global climate. Dr. Christy argues that this is a plausible alternative explanation to man-made global warming because "we", as he puts it, are finding that the climate is not sensitive to greenhouse gases, and he claims that observational data is not consistent with climate model predictions. Thus, Dr. Christy concludes, reducing greenhouse gas emissions will have little impact on the climate.
As you can see, this is a very similar alternative hypothesis to that put forth by Dr. Lindzen. In fact, when Dr. Christy says "we" are finding that the climate is insensitive to greenhouse gases, he refers exclusively to studies by Dr. Lindzen and Dr. Spencer. Virtually all other climate science research has found that the climate is indeed quite sensitive to greenhouse gases, and the work of Dr. Lindzen and Dr. Spencer concluding otherwise contains numerous errors. And as with Dr. Lindzen's alternative hypothesis, every single one of Dr. Christy's arguments is directly contradicted by the observational data (as illustrated in the links above).
Thus unfortunately we once again find that even the arguments by climate scientist "skeptics" that we need not worry about global warming or greenhouse gas emissions are scientifically unsound. There's an important distinction to be made here: human-caused global warming is a robust scientific theory which is supported by a vast body of evidence and has withstood extreme scientific scrutiny for many decades. The alternative hypotheses like that of Dr. Christy, on the other hand, have quickly been falsified by ongoing scientific research.
Additionally, another critical point which Dr. Christy neglects is that even aside from climate change, our carbon emissions are also causing ocean acidification (another major environmental problem which we refer to as "global warming's evil twin"), and there are numerous other issues with our continued reliance on fossil fuels (i.e. peak oil, air pollution, reliance on foreign energy sources, etc.). It's unfortunate that Dr. Christy and his two "skeptic" colleagues continue to present this misleading and scientifically unsound information to the general public and policymakers, because the more we listen to them and the longer we wait, the worse the consequences will be.
NOTE: As you can see from yet another of John Cook's snazzy buttons at the top of this post, we have launched a comprehensive Christy Crocks page very similar to Monckton Myths and Lindzen Illusions. We hope people will make use of these resources to respond when these "skeptics" are referenced. The short URL for the Christy Crocks page is http://sks.to/christy
[DB] Fixed link.
[DB] Hot-linked URL's.
IN THIS ONE YEAR![DB] Please refrain from all-caps usage.
Surprise surprise, Christy is saying bucking the trend on 2014 as the warmest year:
Satellite Data: 2014 'Not Even Close' to Warmest Year
dvaytw @96, interesting link.
It tells me that NewsMax (which I had never heard of before) is an unabashed propoganda site. Quoting Monckton, and using his propaganda terms ("the great pause") as though they were a common term among scientists (as opposed to never having been used by scientists, SFAIK) makes that clear. It also manages to suggest that a measurement of the average across the lower tropopheric temperatures (sort of) refutes the results of surface measurements - as though humans actually live floating two or three kilometers in the air rather than with their feet firmly on the ground.
Roy Spencer's blog post is better, both because it avoids the propaganda excesses of the NewsMax piece, and because it is clear that they are talking about the Satellite record only (although they do not bother to clariffy what that means). It remains disappointing, however, for it fails to mention the ovious fact that lower tropospheric temperatures are far more strongly influenced by ENSO than are surface temperatures. Therefore it is not surprising that while the ENSO neutral 2014 topped the El Nino influenced 1998 and 2010 in the surface record, it did not do so in the sattelite record. Disappointingly it trys to suggest an El Nino influence on the 2014 temperatures due to ENSO features durring December, entirely failing to mention the 6 month lag between ENSO events and their peak temperature influence.
Finally, Christy and Spencer make a big point about the close values of 2014 with 2005 (4th warmest) and 2013 (5th warmest). The clearly mention that there is only a 0.01 C difference between 2005 and 2014, and a 0.02 C difference between 2013 and 2014. The odd thing is that on their own figures, the later is actually a 0.03 C difference. Worse, the actual annual mean for 2014 using their monthly figures is 0.275, which should have been rounded up, not down as they do. The actual differences, rounded to three significant figures are 0.013 C for 2005, and 0.039 C for 2013. Via a non-standard rounding and a simple reporting error, they have virtually halved the reported difference between 2013 and 2014. I suspect that as a result, 2014 is statistically warmer than 2013. Unfortunately I do not know their stated measurement error.
[JH] NewsMax is the Fox News of wire service jounalism.
Christy also cherry-picks the period 2002-2014 for his trend analysis. Any start date 1999-2006 yields a higher central figure. They only deceipt Christy managed to resist is rounding the trend (0.047ºC/decade) down and more correctly rounds it properly up to a "rate of 0.05 degrees Celsius per decade."
Thanks for understanding my mangled sentence there, guys. Glad to have the jump on the talking point for a change.
Jonicol
The science behind greenhouse gasses was settled science in the 1800’s.
It would appear that you cannot find anything which goes deeply enough into the science to show "WHY" they are wrong is because they have not presented any actual real science to support their claims.
They are wrong because over 100 years of science has consistently shown ,with the same reliability that gravity also shows, over and over that greenhouse gases trap heat: Hence the name “greenhouse.”
One of them claims that they “are finding that the climate is insensitive to greenhouse gases” but this alleged “they” is a very small group of scientists who while continually make the claim, have produced no actual science for anyone to debunk. They need to prove that 100 years of science consistently showing ,with the same reliability that gravity also shows, over and over that greenhouse gases trap heat, is now magically wrong.
You question is akin to asking people to prove that gravity is responsible for keeping us from naturally floating away into space.
A very large volcanic eruption can screw the weather up for years, one could even argue that it can affect the climate in the short term. We currently spew out around, or at least, 100, of all the world’s volcanoes combined, a year of CO2.
While the climate may not be sensitive to one of my methane greenhouse gas farts, science has proven that it is affected by all that CO2 that has been pumped into the atmosphere.
Your first hint that they have no science is that their statement puts no limits on the greenhouse gases that “they found that the climate is insensitive to.” If one were to replace the atmosphere with nothing but methane, a greenhouse gas, and oxygen (and possibly some other gasses): It would insensitive the climate into high orbit right around the time of the first lightning strike after said greenhouse gas was introduced in sufficient quantities.