On April 18, 2017 the Syracuse Post Standard published a featured editorial by Dr. Cornelius Murphy, Jr. “EPA Chief is wrong on the greenhouse gas effect”. I was given the opportunity to submit a rebuttal but was asked to make it the same length. This presents a problem because of the Baloney Asymmetry Principle, the third of my pragmatic environmentalist principles. In particular, the amount of information necessary to refute BS is an order of magnitude bigger than to produce it. This post rebuts his arguments.
Dr. Murphy’s editorial is an example of the straw man fallacy prominent amongst the critics of the current EPA. He describes the science behind the greenhouse effect and claims that Administrator Pruitt disagrees with those facts to support his claim that Pruitt must not be allowed to provide direction and policy for CO2 mitigation. The Catastrophic Anthropogenic Global Warming (CAGW) hypothesis espoused by Dr. Murphy claims that mankind’s emissions of greenhouse gases are responsible for the recent observed warming of the globe and, unless stopped soon, will have catastrophic impacts on the planet. This post addresses the catastrophic component of global warming which, I believe, are not obvious by simply “looking around” as Murphy suggests.
Robust scientific theories and hypotheses rely on a combination of both empirical and correlative evidence. In the case of a theory that cannot be directly tested through a controlled experiment, we have to rely on long term observations and comparison of projections based on the theory against the observations. Empirical observations and correlative evidence for the CAGW hypothesis are not as obvious as Murphy implies.
I have no issues with Dr. Murphy’s description of the greenhouse effect. The basic greenhouse gas theory is not controversial. Carbon dioxide is a greenhouse gas. It retards radiative cooling. All other factors held equal, increasing the atmospheric concentration of CO2 will lead to a somewhat higher atmospheric temperature. It is not controversial that CO2 has risen in the last century or that at least half of the increase was due to mankind. It is also obvious that average temperatures are increasing over that same period. Dr. Murphy said that Administrator Pruitt “doesn’t think that CO2 is responsible for heating our planet”, but I don’t think Mr. Pruitt would dispute any of the aforementioned facts.
However, those facts do not necessarily lead to catastrophe and there is a healthy debate on most policy-relevant aspects of global warming. In the first place, there is a predicted warming due to greenhouse gases when all factors are held equal but all other things are never held equal in meteorology. In that case, doubling the concentration of atmospheric CO2 from its pre-industrial level would reduce outgoing infrared radiation by about 4 watts per meter squared and the temperature of the atmosphere would increase about 1.2 deg. C. Note that about half of this warming has already occurred. So clearly some of the observed warming is caused by this effect.
The most recent warming period started before the recent rise in CO2. There have been other warm periods of the same magnitude of the current period in the last two thousand years when anthropogenic CO2 was not the driver. At a minimum the CAGW theory has to explain why the causes of the warming between 1900 and 1940 which is of the same order of magnitude as the current warming are not playing a role now.
Dr. Murphy says that Administrator Pruitt should look at what is happening around him and cites several examples: “We have wild extremes in temperatures but annual average global temperatures continuing to rise. The temperatures of our Great Lakes are 6 degrees above average, extreme weather events challenge us all too frequently, and we experience mega droughts globally on a regular basis.” I address those points below.
I do not dispute that annual average global temperatures continue to rise. However, to me, if there is a valid concern about rising temperatures, then we should be able to find evidence that heat waves are increasing. The EPA climate change indicators high and low temperatures web page lists several parameters associated with temperature. The heat wave index shows an overwhelming spike in the 1930’s but there is no suggestion of a recent trend. There is a trend in the area of unusually hot temperatures graph but I wonder how they addressed the development of heat islands in that data so I am skeptical. I see nothing happening to warrant alarm.
His only quantitative claim is that “the temperatures of our Great Lakes are six degrees above average” but his claim does not withstand scrutiny. According to EPA’s Climate Change Indicators web page on Great Lake temperatures: “Since 1995, average surface water temperatures have increased slightly for each of the Great Lakes”, but that is nowhere near six degrees. The web site Great Lakes Statistics lists the current temperatures relative to their period of record starting in 1992 and all five lakes are currently less than two degrees above the mid-April average.
Dr. Murphy says extreme weather events challenge us all too frequently insinuating that they are getting worse but, again, looking at data indicates no cause for alarm. In recent testimony before the House of Representatives, Dr. Roger A. Pielke, Jr. addressed trends of extreme events in the United States. He noted that global weather-related disaster losses as a percentage of Global GDP are trending down since 1990; that there is no trend in hurricane landfall frequency or intensity; that the IPCC noted no evidence of a trend for floods; that US flood impacts are going down; and that there low confidence in observed trends for hail or tornadoes.
Dr. Murphy says that we experience mega droughts globally on a regular basis but Dr. Pielke quotes the IPCC: “there is low confidence in detection and attribution of changes in drought over global land areas since the mid-20th century”. If the Intergovernmental Panel on Climate Change concludes no trends in droughts then the only way we can interpret the regular basis comment is that this has been the case in the past and it continues today. His statement is not wrong but it also is not cause for alarm upon inspection either.
Because it is impossible to run a controlled experiment on Earth’s climate (there is no control planet), the only way to “test” the CAGW hypothesis is through models. If the CAGW hypothesis is valid, then the models should demonstrate predictive skill. However the models are not predicting temperatures well enough to meet that standard because they predict a sensitivity to CO2 two to three times greater than that supported by observations. Dr. Curry’s summary of the global climate models makes five points about the use of these models for this purpose:
- GCMs have not been subject to the rigorous verification and validation that is the norm for engineering and regulatory science.
- There are valid concerns about a fundamental lack of predictability in the complex nonlinear climate system.
- There are numerous arguments supporting the conclusion that climate models are not fit for the purpose of identifying with high confidence the proportion of the 20th century warming that was human-caused as opposed to natural.
- There is growing evidence that climate models predict too much warming from increased atmospheric carbon dioxide.
- The climate model simulation results for the 21st century reported by the Intergovernmental Panel on Climate Change (IPCC) do not include key elements of climate variability, and hence are not useful as projections for how the 21st century climate will actually evolve.
Finally, Dr. Murphy notes that Pruitt is not a scientist but is an attorney. Although Dr. Murphy is a chemist and not a meteorologist like me I don’t believe that a person’s background necessarily means much. Look at the evidence yourself. When you check the numbers and claims like I did then you can determine whether or not to believe whoever is making the claims. In this case I find little support for Dr. Murphy’s claims but readers should decide themselves.
I have not found sufficient evidence to convince me that CO2 mitigation efforts are appropriate at this time. While it is very likely that human activities are the cause of at least some of the warming over the past 150 years the question is how much. There is no robust statistical correlation to indicate that CO2 is the primary driver. The failure of the climate models outline above clearly demonstrates the CAGW hypothesis is flawed.
I conclude that our children and grandchildren are not in imminent danger from CAGW and would be better served by investments to make society more resilient to observed extreme weather rather than trying to mitigate CO2 emissions to try to prevent the speculative weather projected by the flawed models. I believe Administrator Pruitt’s agenda to reign in the ill-conceived CO2 mitigation programs of the Obama Administration is appropriate. On the other hand, I do not agree with any plans to cut the climate monitoring and observing programs at EPA and elsewhere. I support research into all the causes of climate change not just anthropogenic causes. Ultimately, until such time that a cheaper alternative to fossil fuels is available society will continue to use them because of their tremendous benefits. If you believe that we society should stop using fossil fuels then research and development for alternatives is appropriate.