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Two Greenhouse Gases on the Rise Worry Scientists

from the Atlanta Journal-Constitution (Registration Required)

WASHINGTON (Associated Press)—Carbon dioxide isn't the only greenhouse gas that worries climate scientists. Airborne levels of two other potent gases—one from ancient plants, the other from flat-panel screen technology—are on the rise, too. And that's got scientists concerned about accelerated global warming.

The gases are methane and nitrogen trifluoride. Both pale in comparison to the global warming effects of carbon dioxide, produced by the burning of coal, oil and other fossil fuels. In the past couple of years, however, these other two gases have been on the rise, according to two new studies. The increase is not accounted for in predictions for future global warming and comes as a nasty surprise to climate watchers.

Methane is by far the bigger worry. It is considered the No. 2 greenhouse gas based on the amount of warming it causes and the amount in the atmosphere. The total effect of methane on global warming is about one-third that of man-made carbon dioxide.