As the climate warms, thawing permafrost could have a major impact on the world's climate, but that potential is overlooked in many climate models and studies, warns a new report from the U.N. Environment Programme.

The analysis, released as the latest round of U.N. climate talks began in Doha, Qatar, recommends that the Intergovernmental Panel on Climate Change undertake a special report on permafrost and its role in climate change. The UNEP report also urges countries with significant permafrost deposits -- including the United States -- to improve their monitoring of the frozen ground.

Data gathered by existing monitoring networks "indicate that large-scale thawing of permafrost may have already started," the U.N. report says.

That is a concern because permafrost, which covers 24 percent of exposed Northern Hemisphere land, contains about 1,700 billion metric tons of carbon -- roughly twice the amount currently stored in the atmosphere.

With Arctic temperatures warming twice as fast as the global average, scientists estimate thawing permafrost could release large amounts of carbon into the atmosphere through the end of the century with significant climate impacts.

Thawing permafrost could emit 43 billion to 135 billion metric tons of carbon dioxide equivalent by 2100, and 246 billion to 415 billion metric tons of CO2 by 2200, the U.N. report says.

"Uncertainties are large, but emissions from thawing permafrost could start within the next few decades and continue for several centuries, influencing both short-term climate (before 2100) and long-term climate (after 2100)," it continues.

Despite that risk, current climate models do not include the risk of emissions from thawing permafrost, the UNEP analysis warned.

As a consequence, the projections of future climate change made in the IPCC's next major report, due next year, "are likely to be biased on the low side," the new report says, which could hamper efforts to hold man-made warming to 2 degrees Celsius above preindustrial conditions.

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500