By David DeAngelo
Pittsburgh Current Contributing Writer
Welcome back to Checks and Balances. This is a fact-checking column that will analyze the statements of prominent politicians (both local and otherwise) as well as editorials from some prominent editorial boards (both local and otherwise) to see if those statements are, in fact, true.
Before we go any further, here is an ongoing frame of reference for this column: There is an objective reality that we can understand scientifically. Furthermore, individual statements about that reality are true if, and only if, they correspond to what we already understand about that reality. Of course as the science advances, the big picture is always changing, always shifting, but in the end it all boils down to something like this: the statement “snow is white” is true if and only if there is such a thing as “snow” and it corresponds to the visual perception known as “white.”
Here are some examples (in everyday terms) of some true statements:
- The solar system in which we live is about 4.56 billion years old (give or take a few million years).
- Every object in the universe exerts a gravitational pull on every other object in the universe.
- Light travels at about 186,000 miles per second and this rate is constant for all observers.
The evidence for each is so overwhelming that any attempt to deny any of them would entail an even thornier issue of having to explain why all that supporting evidence is somehow wrong. For the age of the solar system to be wrong, for instance, the science of radiometric dating and all of the nuclear physics connected to it would have to be wrong. For Newton’s gravitation to be wrong, all of the classical physics supporting it would have to be wrong. Thanks to Einstein, it turns out it is less incorrect than it is incomplete. For relativity to be wrong, then all of the science supporting Einsteinian physics would have to be wrong.
And so on. If that’s granted, then all else follows.
Whenever these theories are checked, the evidence supports them. As Carl Sagan once said, extraordinary claims require extraordinary evidence. Denying these scientific theories, whether it’s the age of the solar system or gravity or the speed of light, requires extraordinary evidence – none of which has ever been produced. The theories stand as true.
Today, I’d like to fact-check something larger than one specific incorrect utterance from one specific grandstanding member of Congress. Let’s talk about climate-science deniers.
In November 2012, Donald Trump called climate science a hoax. He also said that this hoax was “created by and for the Chinese in order to make U.S. manufacturing non-competitive.” Just last week, he skipped a climate change meeting at the G7. A picture of his empty chair at the meeting told us all we needed to know about his faith in the science.
Before we can debunk this and any other denials out there (a never-ending process, to be sure) we have to establish what’s being denied – the scientific theory of climate change.
So what is the theory itself — not the evidence that the planet is warming up — but the theory that explains all that evidence?
The story begins with a French mathematician named Joseph Fourier (1768-1830). In a thought experiment in the early 1820s, Fourier assumed the existence of a so-called “black body object” (an abstract object that absorbs all forms of electromagnetic radiation from all directions and reflects none of it back) and calculated what the temperature of this object would be if it was in Earth’s place orbiting the sun. He was able to show that this object would be significantly cooler than the Earth is. As a result, we can assume that without an atmosphere this planet would be significantly cooler than it is now, even without climate change. This is the beginning of the discussion of “the greenhouse effect.”
Since then, scientists have discovered that visible light passes through the atmosphere and heats the surface of the planet. It’s the surface that then emits infrared radiation to heat the atmosphere. In 1856, Eunice Newton Foote (1819-1888) demonstrated that carbon dioxide absorbed the sun’s heat more efficiently than “common air.” In 1863 the British scientist John Tyndall (1820-1893) also found that as more carbon dioxide is added to the atmosphere, the atmosphere would be able to retain just a little more water vapor, and with that added water vapor the atmosphere would be just a little more efficient at retaining the infrared heat emitted by the surface that was warmed by the sun.
In 1896, Swedish physicist Svante Arrhenius (1859-1927) was able to calculate the effects of halving or doubling the amount of carbon dioxide in the atmosphere. Halving it would lead to another ice age and doubling it would warm the planet by 5 or 6 degrees.
Since then the evidence has all pointed towards one undeniable conclusion: the planet is getting warmer due to the greenhouse gasses dumped into the atmosphere by human beings.
And there you have it: climate science. The science itself isn’t new. In fact, it’s more than a century old. And it’s most certainly not a Chinese hoax.