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.
2 greenhouse gases on the rise worry scientists
