William Urban: Global warming or global cooling – Monmouth Daily Review Atlas
It’s a good week to ask this! It’s cold out! Now that the Biden administration is embarking on an ambitious program to slow climate change by reducing drastically the fifteen percent of world carbon-dioxide pollution that we produce, we can look once again (sigh) at the science behind it.
Fifty years ago we were told that we were on the verge of an ice age, fifteen years ago Al Gore said that by 2016 we would face irreversible catastrophic warming. Many people take this very seriously. Others remember how past predictions have been exaggerated, how the rapidly rising temperatures of twenty years ago slowed to a high but perhaps sustainable level, and the once steep and almost identical rise of carbon dioxide levels and global temperatures has ended. This, together with past “settled science” announcements about what we should eat and drink, what is healthy or not, and how much we should weigh, should give us pause about changing our lives radically or spending money needed to make life good now. India and China produce more climate-killing gases than we do, and the Europeans aren’t meeting their Paris goals as well as we do. Fracking and coronavirus lockdowns have slowed emissions of greenhouse gases, but that will not last.
I’m not an expert on this, but a friend of mine is. He taught astronomy for years, then worked for some of our most distinguished research laboratories. What I quote here is a summary of a long study he made about five years back and told me to use as I thought fit:
“The basic document underlying most of the discussion on climate change is the IPCC Fifth Assessment Report (AR5), especially part one: Climate Change 2013: The Physical Science Basis. Working Group I Contribution to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change). It is 1552 pages long. Few have bothered to read it, wisely choosing to consult only the summary. Unfortunately, it is ‘a parody of Corporate-Speak,’ almost impossible for non-specialists to understand.”
The central argument is that greenhouse gases trap heat in the atmosphere, causing the global temperature to rise. However, this causes more water to evaporate, and since water vapor is a significant greenhouse gas, that should result in yet higher temperatures. But water vapor produces clouds that block or reflect sunshine, and heated air rising to high altitudes complicates calculations. In any case, we do not see an infinite loop of higher temperatures, more water vapor, and higher temperatures. Since this is not happening, something must be limiting the feedback.
“IPCC does not address this issue. Moreover, it ignores the effect of cloud formation caused by more water vapor: ‘The simulation of clouds in climate models remains challenging.’” Interesting words.
The question remains: how can we explain the increase in global temperature since the start of the industrial era? One explanation simply side-steps “human-caused” pollutants: “Solar astronomers have long suspected that the Little Ice Age [1300-1850] was associated with a long period of observably reduced solar activity…. The problem is the lack of experimental proof. What we do know is that the Little Ice Age was simultaneous with a long period of reduced sunspot activity. But we do not know how this works. Solar activity alone is not capable of accounting for any appreciable cooling, and luminosity changes have been measured quite carefully, to about 0.1%. This is far too small to be significant.”
Nevertheless, there seems to be some correlation. The late twentieth century saw sunspot activity at its highest level since the seventeenth century. Sunspot activity will cease more or less completely by the scheduled time for the next maximum, about 2025. If the astronomers are correct, and activity ceases as they predict, whatever drives activity also drives something else in the sun, then we may be in for another Little Ice Age. A real pessimist could predict a real ice age.
Clear? Well, probably not. What he means is that we need not panic about predictions for a century from now. We should continue to reduce emissions of greenhouse gases, work toward a scientific breakthrough that we can share with the world, and cease worrying about John Kerry flying his private jet to Iceland to accept an award for climate activism that could have been presented by Zoom. Wind and solar are unlikely to completely replace fossil fuels, and while France is getting most of its electricity from carbon-free nuclear plants, everyone else is terrified of a nuclear winter.
Just don’t panic. Scientists do not know everything yet, and although many have turned contradictory information and group-think into faith-based progressive politics, not all of them have. Prominent Democrats still buy ocean-side estates. Sleep well with that thought in mind.
William Urban is the Lee L. Morgan Professor of History and International Studies at Monmouth College.