View Mobile Site

Your Views: Science backing climate change is tricky but valid

POSTED: October 24, 2013 1:00 a.m.

Re: “Science used...purely political,” Friday’s Times: The critic of Joan King’s editorial claims that the “science” in the Intergovernmental Panel on Climate Change is “purely political.” The latest report from the IPCC is not complete, but parts of it may be found at Internet sources, and I took the opportunity to look over it. It’s actually pretty dense with scientific reporting, and fairly dispassionate. I found nothing to merit the charge of “political ... not scientific.”

Now politics does enter in to this type of science, but that’s because of matters ancillary to the report itself.

The concept of anthropogenic (human species caused) global warming goes back to 18th and 19th century science from some big names in math, physics and chemistry, notably Joseph Fourier, John Tyndall and Svante Arrhenius. These culminated in the work of Arrhenius, who wrote a “radiative forcing” equation involving the fraction of carbon dioxide in the atmosphere. Essentially, he speculated that the burning of fossil fuels could forestall the next ice age.

Not everyone agreed, and scientific debate continues to this day, as many researchers work on the problem of climate cycles. These are notoriously hard to predict and analyze because of the number of variables involved, the difficulty of the observations, and the lack of reliable, easily interpreted data from the distant past.

Nor does the entire scientific community to this day accept Arrhenius’ conclusion. Science is like politics in this regard: Seldom does everyone agree. Most of the arguments against it come from questions about the feedback mechanisms that have somehow stabilized the Earth’s heat budget as the radiation from the sun has steadily increased over the past millions of years.

Arrhenius’ equation suggests that more heat is being taken into the Earth’s systems than is being discharged. The amounts are large, but percentage differences small and difficult to measure with certainty. Evidence that the Swedish chemist was correct, however, comes not just from computer models, but from detailed temperature data for the land surface, atmosphere, and the ocean surface, from the expansion of the ocean and, most dramatically, the increased melting of the Arctic ice cap.

In his letter, W.T. Hinds notes that the land surface measurements have plateaued in the past decade — this data is in the IPCC report he maligns — but he fails to note the other manifestations of the additional heat that have continued unabated. (It is well known to any student of basic chemistry that the latent heat required to melt ice is much greater than that required to heat the water once it is melted, so the ice melting may temporarily, at least, stabilize the Earth’s temperature.)

But I assume Mr. Hinds has good intentions, and certainly has the right to his opinion. By the same token, I would hope he would afford Mrs. King the same privilege, and refrain in the future from attacks based on his perception that she is a “leftist” deserving of “special skepticism.”

Delbert Greear
Helen


Contents of this site are © Copyright 2010 The Times, Gainesville, GA. All rights reserved. Privacy policy and Terms of service

Powered by
Morris Technology
Please wait ...