Not Wrong or Inaccurate; Just Bad Timing

How did NEWSWEEK—or for that matter, Time magazine, which also ran a story on the subject in the mid-1970s—get things so wrong? In fact, the story wasn't "wrong" in the journalistic sense of "inaccurate."

So, it's not wrong or inaccurate, but they got the timing wrong - and had the predictions reversed as it should be global warming, not cooling that we should be worried about.

Some scientists indeed thought the Earth might be cooling in the 1970s, and some laymen—even one as sophisticated and well-educated as Isaac Asimov—saw potentially dire implications for climate and food production. After all, Ice Ages were common in Earth's history; if anything, the warm "interglacial" period in which human civilization evolved, and still exists, is the exception. The cause of these periodic climatic shifts is still being studied and debated, but many scientists believe they are influenced by small changes in the Earth's orbit around the Sun (including its "eccentricity," or the extent to which it deviates from a perfect circle) and the tilt of its rotation. As calculated by the mathematician Milutin Milankovitch in the 1920s, these factors vary on interlocking cycles of around 20,000, 40,000 and 100,000 years, and if nothing else changed they would be certain to bring on a new Ice Age at some time. In the 1970s, there were scientists who thought this shift might be imminent; more recent data, according to William Connolley, a climate scientist at the British Antarctic Survey who has made a hobby of studying Ice Age predictions, suggest that it might be much farther off.

And they'll continue harping on global warming until the next trend of global cooling reemerges as the evidence once again points in that direction.

Also, there's the not insignificant fact that a minor change in the solar output would overwhelm any and all human actions on the environment. Or that major volcanic eruptions (on a scale of Krakatau or Santorini) would affect the world's climate in more than a few ways - including changes in temperature.

The point to remember, says Connolley, is that predictions of global cooling never approached the kind of widespread scientific consensus that supports the greenhouse effect today. And for good reason: the tools scientists have at their disposal now—vastly more data, incomparably faster computers and infinitely more sophisticated mathematical models—render any forecasts from 1975 as inoperative as the predictions being made around the same time about the inevitable triumph of communism.

Funny, but scientists 20 years from now would make the same argument about the status of today's models. Back in the 1970s, the models put together were similarly sophisticated - for the day. Now, they're quaint with comparatively few data points and limited computer horsepower to churn out the data. Every year brings new data points and new analysis, but if you put garbage in, you'll get garbage out. And so much of this is based on assumptions and guesstimates.

Ever wonder why the forecast for the weather a week out is invariably off by a few degrees or that it rains when it is supposed to be sunny? That's because the models - and there are quite a few different models (see these for hurricanes), churn out results based on different data points. Some conflict and the meterologists and climatologists have to interpret and then make their best guess as to what will happen. That's what happened with this year's hurricane season - a prediction of X storms was made at the outset, but the scientists reduced the number of storms predicted throughout the course of the season, and the continental US was spared of any significant storms at all. Sometimes the guesses and models work out to be fairly accurate, but other times they're off - and wildly so.

Now, expand the models to a planetary scale and the forecast isn't for next week, but 50 years from now.

The fact is that the scientists are working with models that may invariably be held to be inaccurate or that they've used the wrong assumptions in which case, their predictions of doom and gloom will be wrong (either too high or too low).

Predictions are a tool, but the global warming predictions are being used politically and to affect economic and social changes when the science is not at a point where it can make such predictions accurately or with certainty.

Reducing certain emissions because it improves air quality is an eminently sensible and good idea (eg: reducing particulates and NOx would reduce asthma and other respiratory ailments), but forcing the world to reduce those emissions globally (and not all nations participating to boot) because of a fear of global warming is a political and economic decision, not one based on science.

UPDATE:
Others blogging the Newsweek story and its admission 31 years later that their original story was incorrect (I'd posit that Newsweek simply got its timing wrong - they could be right in a few years when new research reveals cooling is upon us, not warming) include Sensible Mom, Polipundit, Ace, Tammy Bruce, Dan Gainor, Right from the Right, Dogwood Pundit, Gina Cobb, and Steve Sprueill.

Technorati: global warming, global cooling, junk science, climatology, meterology, climate change.