Earth as seen from a NOAA weather satellite. Photo: NOAA/NASA
As a climate scientist who is trained to base his conclusions strictly on scientific evidence and not politics, I find it particularly troubling that Scott Pruitt, President Trump’s pick to head the U.S. Environmental Protection Agency (EPA), is misrepresenting the scientific data that shows the earth’s atmosphere is warming.
Pruitt hopes to run the agency responsible for protecting the lives and health of Americans from environmental threats, and that includes reducing greenhouse gas emissions that are warming the planet. And as the Supreme Court has ruled, EPA has the authority to address greenhouse gases.
However, in his testimony before the Senate Environment and Public Works Committee on January 18, and then in follow-up written answers to Senators, Pruitt made several misleading, or flat-out inaccurate, statements.
In his attempt at subterfuge, Pruitt leaned on false and misleading climate-skeptic myths that have been debunked time and time again.
For instance, consider this one question and answer:
Written question from Sen. Jeff Merkley: Are you aware that each of the past three decades has been warmer than the one before, and warmer than all the previous decades since record keeping began in the 1880s? This trend is based on actual temperature measurements. Do you believe that there is uncertainty in this warming trend that has been directly measured? If so, please explain.
Written answer from Scott Pruitt: I am aware of a diverse range of conclusions regarding global temperatures, including that over the past two decades satellite data indicates there has been a leveling off of warming, which some scientists refer to as the “hiatus.” I am also aware that the discrepancy between land-based temperature stations and satellite temperature stations can be attributed to expansive urbanization within in our country where artificial substances such as asphalt can interfere with the accuracy of land-based temperature stations and that the agencies charged with keeping the data do not accurately account for this type of interference. I am also aware that ‘warmest year ever’ claims from NASA and NOAA are based on minimal temperature differences that fall within the margin of error. Finally, I am aware that temperatures have been changing for millions of years that predate the relatively short modern record keeping efforts that began in 1880. (Questions for the Record, page 145)
In response to the scientific evidence that the last three decades have each been warmer than the one before it, Mr. Pruitt offered negligent claims that both the satellite data and surface based observations have shown there to be no warming over the last two decades – the so-called global warming hiatus.
Science does not agree with this assessment.
The idea of a hiatus and a potential discrepancy between satellite and surface based data have been under intense objective scrutiny by the scientific community for some time – and the results are in:
- NOAA scientists recently published a peer reviewed article in the Journal Science that clearly shows the “hiatus” to have never existed.
- Then last month a follow up study, undertaken by a separate group of researchers as an objective check on the NOAA result, also confirmed that the global warming hiatus never happened.
- Additionally, the alleged satellite discrepancy has also been debunked – its origin an artifact of necessary, but potentially faulty, post-processing techniques that are employed when using data gathered by a satellite from space, as opposed to direct surface temperature measurements from thermometers. Stated plainly, raw satellite observations from space are not as accurate as those taken in the actual location, so these raw observations need to be quality controlled for scientific accuracy.
Next, in the same answer, in what can only be described as countering his own misguided narrative, Pruitt attempted to blame the increasing temperature trend – which he just stated did not exist via the hiatus argument – on an unfounded discrepancy between satellite based and urban land based data.He claimed the increase in urbanization was causing a fictitious rise in global temperature – an impact long shown to be minimal at best, especially when applied to the massive geographic expanse of the world relative to the lesser change in the geographic extent of cities.
Pruitt went on to quibble with the fact that 2016 was the warmest year ever recorded, by overemphasizing the role of negligible differences in how various scientific agencies around the world calculate the globally averaged temperature.
Actually, the diversity of approaches is a scientific strength, because it provides a balanced view of the data – much like seeking a second opinion on a medical diagnosis. It’s vital to note that despite these trivial differences in methodology, the three long-running analyses by NASA, NOAA, and Great Britain’s UK Met Office all showed 2014 to 2016 to be the three consecutive warmest years on record. This fact is indisputable.
Pruitt concluded his misdirection by pointing out his awareness that temperatures have been changing for millions of years, and predating the relatively short modern record. Mr. Pruitt is indeed correct that the rapid warming in recent decades is quite alarming in the context of the much slower and longer term natural changes – although I don’t think that was what he was trying to say.
Pruitt seemed unaware of the latest scientific evidence on the various topics he chose to explore during his testimony. That indicates an ignorance of science coupled with a lack of preparation which adds up to being unfit to lead a scientifically-based government agency.
