With baseball season in full swing, it’s good to remember that in science, nature bats last. Spin all the theories you like, throw curves at the media to draw attention (i.e., funding) to your favorite issues, or even toss knuckleballs at unruly congressional hearings–but in the end, reality will intervene.
That’s the way things must play out on the field of environmental science. The visitors–in this case, the out-of-towners who want to take over the league–can pile up huge leads, but at the end of the game, the truth squad comes to the plate.
So, for example, though newspapers bludgeon readers with daily stories of global warming horrors, life goes on. In fact, it is getting better, what with the severity of winter slightly diminished, the growing season slightly lengthened, and dramatic increases in food production and human longevity. Eventually people realize that there is a phenomenal disconnect between what the announcers are saying and what the score really is.
The pollsters say so. Despite all the current noise, “environment” ranks way down in the league of political importance, and on the Green Nine, global warming is at best a benchwarmer. People are clearly much more concerned about $2-per-gallon gasoline than they are about the fact that burning it makes the air less cold.
The problem is that global warming is getting old and no longer has the punch it once had. The first time the subject led off a network news show was in October 1983–17 years ago. Since then, the mean surface temperature has risen about 0.20ºC. (Computer models from that era predicted the warming would be 0.68ºC, more than three times what was actually observed.)
While global warming was working its way up through the minor leagues of environmental concern, temperatures were also rising–at exactly the same rate as they had in the decade and a half prior to 1983. That gives us easily three decades, or nearly half a lifetime, of dreaded heating.
In those last three decades, world production of wheat, corn, and soybeans combined rose from around 1800 kilograms/hectare to around 3200, or 78 percent, while population rose 50 percent. In short, we now produce considerably more food per living person than we did back then. Life expectancy in the United States rose about seven years, or one-tenth of a lifetime. (Don’t even ask about your 401(k) account, just let it grow.)
Those are the unvarnished truths about the human condition vis-à-vis global warming.
What about the so-called comeback of the Green Nine’s benched team member, the “ozone hole”? That one concerned us enough that we “did something,” instituting a ban on the production of some chlorofluorocarbons (CFCs) that we thought might be causing a large part of the problem.
Now, it’s back, and it’s not alone. Instead, it has teamed up with aging global warming in an attempt to rally the flagging environmental doomsayers. NASA scientists recently announced that, despite falling concentrations of CFCs, ozone depletion is accelerating in the North Polar stratosphere in late winter and early spring. That’s the season during which annual depletions peak because the sun, which catalyzes the formation of ozone, has been below or near the horizon for months. When the sun gets high enough in the sky to hide fly balls, ozone has been replenished.
So NASA now tells us ozone is still being depleted around boreal sunrise, despite the reduction in CFCs, because the same changes in the greenhouse effect that cause global warming also happen to induce stratospheric cooling, which hastens ozone depletion. That linkage of two aging issues is likely to strike out.
That’s because humans are merely returning the atmosphere to its more “natural” greenhouse effect, a state that has characterized much of the history of large-scale life on the planet. Though we hear (incessantly, around Earth Day 2000) that soon carbon dioxide levels will be higher than they have been for a few million years, those levels were in fact much higher in (at least) the previous 290 million years, and they dropped concurrently with the global cooling that created the ice ages. Be aware that correlation here does not imply causation.
All of this means that when the planet was teeming with dinosaurs, cycads, and whatever else fossilized itself into whatever makes General Motors go, the Earth’s natural greenhouse effect was several times greater than it is today. Which means that the stratosphere was several degrees colder. Which means that every time a big volcano went off (and there were more on a younger Earth), enough chlorine was blown into the stratosphere to cause a hole in the ozone.
Nature really does bat last. She survived through all those innings when ultraviolet radiation rained down through the naturally low stratospheric ozone. And in doing so, she reveals the truth about the current environmental game.