John Ward, in the Gainesville Sun, discusses the science of climate change and finds it just that, and not theory.
Comments by OSFR historian Jim Tatum.
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John Ward: Cause of climate change is settled science
Several years ago, a Florida legislator replied to my global warming concerns by saying that before doing anything, “We should work to decide if the cause is man-made or a natural heating and cooling cycle of nature.”
This is the strategy to avoid climate action that Frank Luntz recommended to George W. Bush in 2003: “Should the public come to believe that the scientific issues are settled, their views about global warming will change accordingly. Therefore, you need to continue to make the lack of scientific certainty a primary issue in the debate.”
The legislator’s reply to me continued, “The consensus of science … does not make it correct. One just needs to go back in history when the scientific consensus believed that the Earth was the center of the universe or that it was flat. Can you imagine where we would be today if we did not continue to explore and seek more information?”
Can you imagine seeking more information on those questions today? Thousands of climate scientists now explore and seek information about a multitude of issues related to the rising heat and changing climate, but the cause is settled. It is heat-trapping gases, emitted by human activities. It has been confirmed by thousands of experiments and has withstood all challenges for over a century.
Around 150 AD, Claudius Ptolemy developed a theory that supported the perception of the sun and stars revolving around an unmoving earth. He based it on a large accumulation of historical measurements that had predictive value and remained the consensus view for over 1,400 years. It was a consensus that was hardly challenged during that time, since the Catholic Church backed it. Like the flat-earth idea, it was easy to accept, because it looks that way.
It’s also natural to believe that human activity cannot affect climate, because sunlight, wind and other natural forces appear to simply happen. For millions of years, humans didn’t affect climate. But, as in the earlier examples, scientists became aware of things going on that didn’t fit with the traditional explanations or perceptions. Nineteenth century scientists noticed that our planet was warmer than its distance from the sun could explain and posited that certain gasses, particularly CO2, prevented some of the heat emitted by sun-warmed surfaces from leaving our atmosphere. They confirmed this heat-trapping quality in tests.
Svante Arrhenius learned that factories burning coal emitted CO2. In 1906 he predicted that growing emissions would raise global temperatures enough to prevent another ice age. Unlike Ptolemy’s theory, Arrhenius’s claims were quickly challenged, and further challenges arose as global warming became the subject of more widespread research. This helped refine and improve our understanding of the subject. But Arrhenius’s basic findings have held up surprisingly well.
Every national and international scientific association taking a position on the subject agrees that humans are primarily responsible, as do 97 percent of climate scientists. Ten studies show that human emissions caused more or less all of the global temperature rise since 1950. This scientific consensus convinced every nation in the world — except ours — to endorse the Paris pledge to cut heat-trapping gas emissions. A few climate scientists and many non-scientists claim the issue isn’t settled, but the research they offer is flawed and lacks predictive value. None of it has exposed reasons to doubt the consensus view.
Further climate change research is important, but, given what we already know, cutting heat-trapping gas emissions as quickly as possible to preserve something resembling the climate to which humans have adapted and around which we have built our economy and way of life is even more essential. Existing uncertainty about the degree of an overheated world’s dangers presents a much greater chance for it to be worse and happen sooner — as much new research warns — than to be less serious than scientists currently expect.
These threats endanger the rights, needs and desires that the preamble of America’s Constitution declares it was written to establish, insure, provide, promote and secure, concerns that shaped the document every federal legislator swears an oath to support and defend. You can help by telling our legislators that we need urgent, effective action to address the problem while that’s still possible.
John Ward lives in Gainesville.