In today’s American Spectator, I outline the politicization of climate science, and note one of the media’s most well-guarded secrets: that scientists continue to poke holes in the theory of man-caused, catastrophic global warming. Happily, The Heartland Institute has a new book out that helps make my case: Climate Change Reconsidered: 2011 Interim Report.
From my column:
If supposed greenhouse gas emissions were causing global warming, then we should have seen a far more steady increase in temperatures. What the objective scientists are now saying is that this up and down pattern of temperature is far more consistent with natural causes. The temperature variation patterns follow variations in solar activity (like sunspots) and major ocean current temperature trends. For example, a major influence on global temperatures is what is known as the Pacific Decadal Oscillation (PDO), which turns from warm to cold and back every 20 to 30 years, as cold water from deep in the ocean cycles up and is warmed by the sun. This PDO variation seems to follow closely with the actual temperature variation trends.
Global temperatures were also warmer than today during theMedieval Warm Period, a period of several hundred years around 1000 A.D, when now icy Greenland was named and actually farmed by settlers (who long since fled as the cold and ice advanced). Even higher temperatures prevailed during a period known as the Holocene Climate Optimum, which ran roughly from 6000 B.C. to 3000 B.C. In fact, temperatures were higher than today during most of the period from 9000 B.C. to the birth of Christ. Yet, there was no significant human burning of fossil fuels during these periods.
CO2 is a naturally occurring substance in the Earth’s atmosphere essential to life. Plants need to take in CO2 to live, and emit oxygen, which is essential to animal life. Animals breathe in oxygen and emit CO2. Proxy records scientists use to reconstruct the past show that atmospheric concentrations of CO2 were much higher in the past than today. For hundreds of millions of years prior to 400 million years ago, atmospheric CO2 concentrations were well over 30 times greater than today. But CO2 concentrations have actually been in sharp decline since then. From roughly 50 million back to 350 million years ago, fluctuating CO2 concentrations were generally 3 to 15 times their current levels. Princeton’s Happer argues that we have been suffering a CO2 famine that has harmed plant life and agriculture.
CO2 concentrations have begun rising again, due primarily to the industrial revolution and increased burning of fossil fuels, up 44 percent from 150 years ago. And this is already causing more rapid growth of plant life. But CO2 still accounts for only 0.039 percent of all atmospheric molecules, less than 1 percent of the concentration in human breath.
Moreover, humans and their activities currently account for only 3 percent of CO2 emissions each year. And less than half of the CO2 emitted by fossil fuel burning remains in the atmosphere; the rest is absorbed by the ocean or incorporated by the terrestrial biosphere. This is why policies to reduce human CO2 emissions such as the Kyoto treaty, even if fully implemented, would have negligible effects on future temperatures, reducing the temperatures that would otherwise result by 0.02 degrees C by 2050 for Kyoto, as conceded by even global warming alarmists.
Read the whole thing.