The Earth Cools, and Fight Over Warming Heats Up

Many Scientists Say Temperature Drop From Recent Record Highs Is a Blip, While a Few See a Trend; Inexact Climate Models

By JEFFREY BALL
WSJ

Two years ago, a United Nations scientific panel won the Nobel Peace Prize after concluding that global warming is "unequivocal" and is "very likely" caused by man.

Then came a development unforeseen by the U.N.'s Intergovernmental Panel on Climate Change, or IPCC: Data suggested that Earth's temperature was beginning to drop.

Global climate models did not account for a drop in global temperatures since 2006, but climate scientists believe the lower temperatures are temporary.

That has reignited debate over what has become scientific consensus: that climate change is due not to nature, but to humans burning fossil fuels. Scientists who don't believe in man-made global warming cite the cooling as evidence for their case. Those who do believe in man-made warming dismiss the cooling as a blip triggered by fleeting changes in ocean currents; they predict greenhouse gases will produce rising temperatures again soon.

The reality is more complex. A few years of cooling doesn't mean that people aren't heating up the planet over the long term. But the cooling wasn't predicted by all the computer models that underlie climate science. That has led to one point of agreement: The models are imperfect.

(More here.)