It is no secret that a majority of the peer-reviewed climate change literature lays blame for global warming on human greenhouse gas emissions.
But despite the abundance of research supporting anthropogenic global warming, there is a sizable community of qualified scientists who believe the so-called consensus view on global warming is completely wrong. I wanted to find out why, so I contacted one skeptical researcher to ask.
Dr. Roy Spencer is a climatologist at the University of Alabama in Huntsville. For many years he served as a Senior Scientist for Climate Studies at NASA’s Marshall Space Flight Center, and his research has been published in peer-reviewed journals such as Geophysical Research Letters and The Journal Of Climate. Dr. Spencer was kind enough to explain to me what convinced him that the consensus view on global warming is incorrect and what he believes is responsible for the rising temperatures we have observed.
Can you summarize your views on climate change?
I believe that most climate change is natural in origin, the result of long-term changes in the Earth’s albedo (sunlight reflectivity). This alternative explanation for recent warming has seen almost no research, which is a curious situation if science is to progress. Now, I will also say that anthropogenic greenhouse gas emissions must cause some warming, but that its warming influence is small compared to natural, internal, chaotic fluctuations in global average cloud cover.
You say the IPCC has the relationship between temperature and cloud cover completely backwards, and this greatly affects our understanding of how sensitive the climate system is. Can you elaborate?
As we have addressed in a previously published paper in The Journal Of Climate, and elaborate further on in another paper accepted for publication in The Journal of Geophysical Research, natural cloud variations in the climate system give the illusion of a sensitive climate system. This is a relatively new finding, and it is taking time for other researchers to understand its significance to the global warming debate.
By way of background, most climate researchers today believe that global average temperatures are moderately to strongly sensitive to our addition of greenhouse gas emissions, and a large part of that sensitivity argument depends upon cloud cover dissipating somewhat with warming. This is a relationship they see during natural climate variations: warmer years tend to have less cloud cover. If that anomalous warming is indeed causing a decrease in cloudiness, then more sunlight would be let in, magnifying the relatively small amount of direct warming that increasing carbon dioxide produces. This is called positive cloud feedback.
But what they have neglected to consider is the fact that a large part of that observed warmth was caused BY the decrease in clouds, not the other way around. We have demonstrated with a simple climate model that warming can cause an increase in clouds, thus producing a strong brake on warming (negative feedback), but the signal of that process is lost in the noise of natural cloud variations causing temperature variations. It all comes down to mixing up cause and effect. Negative cloud feedback is obscured by natural cloud variations causing temperature variations.
Some climate change skeptics say solar activity is primarily to blame for rising temperatures. What's your opinion on that?
I consider it a highly speculative theory….but possible. There is so much we don’t yet understand about natural climate change. Most researchers today have virtually convinced themselves that there is no such thing. In a way, the sunspot theory is the closest alternative match to my theory because it involves natural variations in cloud cover as the main forcing mechanism for climate change.
You have a new book out aimed at people who are not climate scientists. Tell us about it.
My new book, The Great Global Warming Blunder, lays out the case for clouds as the main cause of global warming. The climate research community has become so inbred and financially dependent upon the continuing threat of manmade global warming that they have trouble even entertaining any alternative hypotheses. So, since the issue is so easily explained, I am getting others out there involved in the physical sciences to look at the evidence.
How significant is the recent climategate scandal to the global warming debate?
I think it is very significant for public perception, but less significant to the climate research community. Climategate has revealed that scientists at the core of the U.N.’s case for humanity as the cause of warming are quite biased and intolerant in their dealings with scientists having alternative views. Those of us who are skeptical that humanity has caused most of the warming have always known this bias exists, but now the public gets to see it on display.
Is CO2 a pollutant?
No, since atmospheric carbon dioxide is necessary for life on Earth, I do not consider it a “pollutant”. Considering this fact, it is amazing that there is so little of it: only 40 out of every 100,000 molecules of air are CO2, and it takes 5 years to increase than number by 1 through the burning of fossil fuels. It might well turn out that more CO2 is, on the whole, good for life on Earth. Hundreds of scientific papers have demonstrated this for various types of plants, and we are beginning to see research that the same might be true for the oceans as well.
What do you think of the various efforts to reduce CO2 emissions?
Command-and-control mechanisms for reducing CO2 emissions are doomed to failure because there are, as yet, no large scale replacements for fossil fuels. Now, since fossil fuels are a finite resource, we do need to be working toward replacements. But they can not be simply legislated into existence. And if we punish the use of energy by making it more expensive, it is the world’s poor that will be the first to suffer.
Since I do not receive any money from Big Oil, I can say that I will maintain this view even if the oil company executives change their minds and support cap-and-trade. Such corporate decisions can be expected as oil companies position themselves for special favors from government if they think cap and trade is inevitable anyway.
For more information, visit Dr. Spencer's website.
Interview With A Global Warming Skeptic: Dr. Roy Spencer