August 20, 2006

Cooler heads on global warming

By: James N. Markels

There’s a storm brewing over global warming–or, more accurately, storms aren’t brewing, and that’s causing a storm in itself. People preaching the dangers of global warming predicted that warmer air meant more and bigger hurricanes, and pointed to 2005’s record-breaking number of storms as evidence of their theory. But now it’s 2006, and there hasn’t even been a single hurricane in the Atlantic yet. We’re below the historical average since 1944. Our chances of another year like 2005, or even 2004, are practically nil. The big storm is turning into a big bust.

Even more interesting, the current explanation for the lack of storms is ocean cooling, as in the surface temperature of the Atlantic is too low to create and sustain hurricanes. This would be truly inconvenient for Florida State University geography professor James B. Elsner, who is about to publish a study this week in the Geophysical Research Letters journal predicting that warmer air creates warmer oceanic temperatures, which is central to the theory that global warming will mean more storms.

So, is the air cooling? Is Elsner’s theory wrong? Are melting polar icecaps lowering the Atlantic’s temperature? What’s the deal?

As a lay person, my guess is no better than anybody else’s. But one thing that seems pretty consistent so far is that our ability to predict the weather hasn’t improved much since the Farmer’s Almanac. The science of global warming isn’t nearly as settled or simple as the alarmists would like to believe, and cooler heads are needed to counter the overheated claims of a global apocalypse.

The simplicity of the global warming theory is in itself deceptive. Greenhouse gasses, primarily carbon dioxide, help trap the sun’s warmth to keep the temperature of the Earth tolerable for life. Since the rise of modern industry, humans have been adding these gasses to the atmosphere, mostly through the burning of fossil fuels, thereby increasing the greenhouse effect and further warming the Earth. All of this is quite true.

And yet, it’s not the whole truth. These greenhouse gasses are responsible for a small percentage of the overall reason for the Earth’s temperature. The lion’s share is caused by water vapor–cloud cover, in other words. So even though carbon dioxide levels have increased roughly 20 percent over the last 45 years, according to some measurements, relatively minor changes in water vapor levels could easily negate or overpower that effect, without any human action at all.

It’s true that the Earth’s temperature has been rising recently. But it’s also true that for millions of years during the time of the dinosaurs, the Earth was about 10 degrees Fahrenheit warmer than today, and was about 4 degrees warmer a mere 5,000 years ago. The Earth has also been through crippling Ice Ages with much cooler temperatures, with the last ice age abating roughly 10,000 years ago. We’ll be due for another ice age eventually as the Earth naturally shifts in its tilt and orbit, in what are called “Milankovitch cycles,” that greatly affect how much sunlight reaches the planet. All without human involvement.

Simply put, humans are putting greenhouse gasses into the air, which causes warming, but that’s not the end of the matter. Natural events also cause warming and cooling, and on far greater scales than what human activity affects. And our understanding of these natural events is still spotty. After all, there was significant global cooling from the 1950s to the 1970s, enough so that people predicted an oncoming ice age, despite steady increases in greenhouse gas production during that period. This is why apocalyptic predictions of rampant global warming always fall short: they assume human action within a stable environment. But nature is not stable.

Predictions of the dire effects of global warming also fall short in that they neglect another crucial piece of information: the dire effects of global cooling. After all, the alternative to global warming is not global “room temperature.” If global warming is supposed to give us bigger and more plentiful hurricanes, what would cooling give us? Shorter growing seasons resulting in less food, for one. More illness from longer winters. Less farmable land as glaciers advance. Ecosystems would still change, just like with warming, only in opposite directions. Instead of polar bears facing shrinking habitats, fennec foxes would suffer. There are tradeoffs either way.

What doesn’t help is the storm of morality-driven condemnation peddled by activists like Al Gore who preach that the human sin of economic success is causing a backlash of nature’s justice. If we’re better off with cooler weather, then let’s do something about it. But is that the case, or are alarmists merely taking advantage of climate change to push their agenda?

We will continue to strive to understand what makes the weather change, but the fact that it is changing doesn’t mean that human involvement alone is to blame. The Earth could be warming regardless of human action, or it could be that we’re helping stave off the next ice age. But one way or the other, looking into the quiet Atlantic, it’s certain that the Earth isn’t sitting on its heels while we play with the controls.

James N. Markels is an attorney and a regular columnist for Brainwash. He is the co-author, with the Institute for Justice, of an amicus brief to the Washington State Supreme Court in Rickert v. State of Washington Public Disclosure Commission.