Nitrous Oxide’s Global Warming Impact No Laughing Matter

Thawing permafrost in the Northern Hemisphere releases "large amounts" of greenhouse gas nitrous oxide, according to a new study from the journal Nature Geoscience.

The study found that under certain conditions thawed permafrost can release as much nitrous oxide as tropical forests, one of the main sources of the gas.
Nitrous oxide, also known as "laughing gas," is ranked third behind carbon dioxide and methane in contributing to global warming, and is regulated under the Kyoto Protocols. According to the EPA, the gas is 310 times more effective in trapping heat than carbon dioxide. Sixty percent of the nitrous in the atmosphere is produced naturally.
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