Sometime in the next 1,000 years our planet will slip into another Ice Age, if the historical cycles of the past continue to repeat.
It will not be pleasant. Where are you going to get food to eat when all of our farms and ranches are covered by a perpetual ice sheet? Last time I looked, there were no more wooly mammoths around — and even if there were, they couldn’t feed the world’s 6 billion people.
It will not be short. Warm periods, such as the one we are currently in, last only about 10,000 years. The cold periods that separate them last about 100,000 years.
The worst prediction I have heard about global warming is that Florida will be completely under water in 500 years. If scientists unlock the secret of immortality and I’m still around at that time, I’ll only be able to reach my Miami condo by gondola. Yet that will be a piece of cake compared to a world in which Miami is approachable only with snow sleds and huskies.
Have you ever wondered why some people hyperventilate about some crises and not others? Why do they froth at the mouth when they think about global warming, but remain almost indifferent to the much more serious threat of global cooling? I have a theory about that. But first a personal confession.
Coming Around Again
What started me thinking about today’s topic was last week’s winter storm — breaking temperature and snowfall records all across the country. Maybe the progression into an Ice Age has already begun, I thought. Then I realized that I too have been swayed by the very silly, totally unscientific rhetoric of the global warming alarmists.
Anyone who pays attention to climate data knows that broad temperature changes occur over thousands of years. Along the way, there can be radical swings in temperature from day to day, week to week and even year to year. A single hurricane. A single snow storm. One year’s temperature record. Even ten years’ temperature record — none of this tells us anything interesting about where we are headed.
Yet we have been encouraged to think just the opposite by headline grabbing alarmists. Here’s amateur climatologist Al Gore telling us that a record snow storm is evidence of global warming. Here’s former Senator Robert Byrd telling us that lack of winter snow is evidence of global warming. Here is an apparently serious year 2000 prediction that English children will never experience snow. Here is a 2009 report on record-breaking snow paralyzing London. One of the worst offenders is someone who should know better: NASA scientist James Hansen, who rarely lets any climate event go by without claiming the event is evidence of global climate change.
Even economists have bought into this. Here is Matt Yglesias telling us that 2010 was the third hottest year on record. “2010 was tied with 2005 for the warmest year on record,” writes Paul Krugman in today’s New York Times. This must come as a surprise to climatologists familiar with the historical record:
- During the Jurassic Period, when dinosaurs walked the earth, the planet was 18o F (10o C) warmer than it is today.
- The earth was also warmer than it is today 500 years ago
- As it was 1,000, 2,000, 2,500 and 3,000 years ago. (See Figure I.)
Source: John P. Bluemle, Joseph M. Sable and Wibjörn Karlén, “Rate and Magnitude of Past Global Climate Changes,” in Lee C. Gerhard, William E. Harrison and Bernold M. Hanson, eds., “Geological Perspectives of Global Climate Change: AAPG Studies in Geology, No. 47,” American Association of Petroleum Geologists, March 15, 2001, pages 193–212.
Almost as bad as the hysteria over annual temperature records, is the hysteria over carbon dioxide (CO2). Are we destroying the planet every time we take our car out for a spin around the block? As Figure II shows:
- There was an explosion of life forms 550 million years ago (the Cambrian Period) when CO2 levels were 18 times higher than today.
- During the Jurassic Period, CO2 levels were nine times higher than today.
Source: Figures based on Monte Hieb, “Climate and the Carboniferous Period: Similarities with Our Present World,” Plant Fossils of West Virginia (Web site), updated September 19, 2006. For temperature data, see C.R. Scotese, “Climate History: Ice House or Hot House?” PALEOMAP Project, April 20, 2002; available at http://www.scotese.com/climate.htm.
Warm temperatures and lots of CO2 are very much pro-life. In the past these conditions produced a planet teeming with life. A world warmer than the one we have today may also be good for human health. But from a purely selfish perspective, I’d like to see the climate stay close to where it is. After all, we’ve invested a lot (including my condo) in the current climate regime.
So the really interesting question is: can we thwart Mother Nature and make the climate stay where it is for our own comfort and enjoyment? No one knows. But as the next Ice Age approaches, conservatives who pooh-pooh the threat of global warming may hope that humans can affect the climate. Liberals who drive around in Priuses because they think they are saving the planet may rush out and buy Hummers instead.
As for sound public policy, economic reasoning suggests a go-slow approach — the opposite of what all the alarmists are saying. And this is true whether you are worried about warming or cooling. Suppose you are willing to commit $100 billion to the welfare of our descendants living 100 years from now. You can spend it on alternative energy and other CO2 reduction activities right now. Or you can invest it at, say, a 6% real rate of return in the economy. If you choose the latter, you can bequeath a sum that will grow to $25.6 trillion in 100 years — about 1 ½ the size of our entire economy at current prices. The longer we delay spending the money, the more funds our descendants will have to deal with the problem later on. As explained by Kevin Murphy (via David Henderson), there is almost no case for spending all, or even most, of the money any time soon.
Now for my theory. The next Ice Age will be caused by Mother Nature. Ditto for an asteroid hitting us from space. Ditto for the earthquake that’s going to send Los Angeles into the sea. But global warming might — just might — be blamed on human beings.
Some people only get excited over crises they can blame on their fellow man. Think nature = good and humans = bad and you will get the picture.