Wednesday, June 17, 2009

The 1998 Canard

One of the favorite talking points of global warming deniers is that temperatures "peaked" in 1998 and have been "falling" ever since. Some go so far as to forecast a new ice age in a few decades given the "rate of decline" since 1998.

This is a good example of taking something that's true and making it entirely misleading by leaving out the "rest of the story."

It is true that the warmest year recorded on earth in the modern era was 1998. Since then, global temperatures have not again reached that peak. But that hardly means its getting cool!

In 1998, we had a very strong El Nino event, which tends to make for warmer weather across the globe. That particular El Nino, combined with the general warming of the earth's atmosphere, contributed to the record year.

In the decade since then, we have seen a number of very warm years. In fact, the planet's 10 hottest years on record are all bunched up between 1997 and 2008--hardly a cooling trend.

Furthermore, the trend continues. While is was relatively cooler in the U.S. the first quarter of this year--only the 24th warmest for that period since 1880--it was hotter around the world, coming in as the 6th warmest for that period. Hardly the beginning of an ice age.

Believe it or not, there is room for some legitimate debates on global warming, and certainly the need for additional research and better data all the time. Unfortunately, the debate is usually so politicized that the facts get obscured.

A new El Nino is brewing in the Pacific. Will it make 2009--or 2010--a record year, eclipsing 1998? Who knows. But we're hardly heading to a new ice age!


charvakan said...

I've argued this point (on a bulletin board I administer at --you're welcome to post if you have the time and inclination) with several AGW skeptics. You're absolutely correct: the 1998 line is classic cherry-picking of the data. It's the only year they could have started from that would give a downward temperature trend. The rolling five-year averages have continued to increase, and of course that's a more accurate measure.

Another line I've heard is that the other planets in the solar system are getting warmer too, and this is evidence for the solar constant as the culprit and not greenhouse gases. Okay, but climate scientists have taken it into account and believe solar radiation fluctuations can account for less than half of the temperature increases.

In science, nothing is proven. The case for anthropogenic global warming is strong but not ironclad. But why not take it seriously? It's not as though people are being asked to return to the stone age, or that they'd do it even if they were asked. Conservation is a good idea in its own right.

X Curmudgeon said...

Good points. Conservation indeed is a good idea in its own right, and so is use of renewable energy resources, especially if they are domestic.

The fact that many global warming deniers also believe earth was created 6000 years ago is not exactly a ringing endorsement for their science.