The rains have returned to California, and the six-year drought appears to be largely over. We have heard countless assertions from journalists and politicians, ignorant of the weather history of California and the other western states, that the drought was a result of global warming.
In the January edition of Scientific American, there is a well-told story “California Megaflood: Lessons from a Forgotten Catastrophe” by B. Lynn Ingram, a professor of earth and planetary science at the University of California, Berkley. She notes: “Geologic evidence shows that truly massive floods, caused by rainfall alone, have occurred in California every 100 to 200 years. The only megaflood to strike the American West in recent history occurred during the winter of 1861-62. California bore the brunt of the damage. This disaster turned enormous regions of the state into inland seas for months, and took thousands of human lives. The costs were devastating: One quarter of California’s economy was destroyed, forcing the state into bankruptcy.” The floods followed “two exceptionally dry decades.”
People are endlessly surprised by some unusual weather, geological, political or economic event, often with the erroneous assumption that such a thing has never happened before. This lack of historical knowledge is not confined to the poorly educated, but often experts in some field or another do not know the history of their own discipline. With the advent of low-cost, powerful computers, mathematical model-building has become all the rage. I am all for model-building, provided the models are tempered with historical reality. A way of testing the predictive ability of a particular model is to compare its predictions against the observed data.
For instance, there had been a pause in global warming for nearly two decades, despite the rise in carbon-dioxide emissions, which none of the major climate models had predicted. Climate scientists Patrick Michaels and Chip Knappenberger of the Cato Institute compared observed warming rates from 1950 to predictions made by 108 models. In virtually all cases, at a statistically significant level, the models projected much higher rates of warming than actually occurred. The fact that models all erred in one direction indicates that they misspecified one or more major variables or they were subject to bias.
The pressure for bias is easy to understand. Most climate studies and models are funded by governments. Governments throw money at what are perceived to be major problems. If researchers come back and say there is no big crisis — then the money faucet gets turned off.
Climate modelers have been perplexed as to why the predicted increase in carbon dioxide that has occurred has not resulted in the predicted higher temperatures. The Earth has become greener as carbon dioxide — which plants need — has increased as a percentage of the atmosphere.
It has also long been known that sunspot activity is correlated with global temperature changes — with warm periods coinciding with higher levels of sunspots and vice-versa. Researchers have also known that clouds have great effect on Earth’s temperature. Some clouds hold in heat; others reflect sunlight — but cloud science is not well understood. Fortunately, researchers at CERN (The European Organization for Nuclear Research), which operates the largest particle physics laboratory in the world in Geneva, Switzerland, appear to have come up with an explanation. Their experiments show that fewer sunspots result in less solar wind, which enables more cosmic rays to reach Earth and create more ionized clouds, which “make clouds more reflective.”
Climate alarmists never tire of saying “97 percent of all scientists agree” without ever providing the exact wording of the question and precisely who was surveyed. Yes, almost everyone agrees that the Earth has been slowly warming since the end of the last ice age, and that man has some influence on climate — particularly micro-climates such as the heat islands that cities cause. That being said, there is much that is not known with precision, such as the real rate of global warming — and thus whether or not it is real problem, how much is caused by man and how and what can be now done in a cost-effective way to deal with it, including adapting to it, or whether we should just leave it to future generations who will have much more knowledge and technology to deal with any climate problems. Shouting “denier” to those who raise legitimate questions neither leads to civil discourse or greater understanding.
Costly regulations and mandates to reduce carbon-dioxide emissions that will have little or no global effect on temperatures over the next century make no sense. There has been no agreement on what the optimal level of carbon dioxide is, or what the optimal Earth temperature should be. We do know that plants grow faster with more carbon dioxide and thus food becomes cheaper, and that most people (including the Hollywood climate activist crowd) prefer warmer places over colder ones.
If the “science was settled,” hundreds of millions of dollars would no longer be spent on trying to understand the various factors that influence climate and trying to build better climate models. Two hundred years ago, many medical doctors thought you could improve a patient by bleeding him or her. Many needlessly died as a result — including perhaps George Washington. The economy is now being unnecessarily bled by the environmental “doctors” who fail to admit their own ignorance.
• Richard W. Rahn is chairman of Improbable Success Productions and on the board of the American Council for Capital Formation.