All the back and forth over climate change negotiations hasn't dealt with a looming problem: melting permafrost could account for more than a third of all warming emissions by 2100, experts warned Tuesday, and yet nations haven't factored it into reduction targets.
"Permafrost is one of the keys to the planet’s future because it contains large stores of frozen organic matter that, if thawed and released into the atmosphere, would amplify current global warming," U.N. Environment Program Director Achim Steiner said in announcing the report by top permafrost scientists.
"Continuing to ignore the challenges of warming permafrost" is not an option, he added.
The report was released as nations gather in Doha, Qatar, this week for the latest round of climate treaty talks that aim to limit warming by the year 2100 to 2 degrees Celsius (3.6 degrees Fahrenheit) above pre-industrial temperatures.
"Permafrost has begun to thaw," lead author Kevin Schaefer, a researcher at the National Snow and Ice Data Center at the University of Colorado-Boulder, told a news conference in Doha.
"Permafrost emissions could ultimately account for up to 39 percent of total (greenhouse gas) emissions," he warned. "This must be factored into treaty negotiations ... or we risk overshooting the 2 degrees Celsius maximum warming target."
Permafrost, defined as ground that stays frozen for at least two years in a row, stores vast quantities of carbon dioxide and methane, both gases that contribute to the greenhouse effect warming the Earth.
Widespread thaw would create a vicious circle, since the release of more CO2 and methane would trap more heat in the air and in turn accelerate the melting. That, in turn, could bring an irreversible, runaway effect.
The experts predicted an irreversible loss of between 30 and 85 percent of permafrost near the surface. That was based on a forecast of Arctic temperatures rising by 6 degrees C (10.8 F) through 2100.
The permafrost report follows reports by the World Bank and the U.N. Environment Program warning that rising world greenhouse gas emissions, even without permafrost contributions, were on track to push up temperatures well beyond 2 degrees C by 2100.
At Doha, nations are negotiating around extending the Kyoto Protocol — a legally-binding emissions cap that expires this year.
Many rich countries such as Japan, Russia and Canada have refused to endorse an extension and want a completely new treaty. The United States was the lone industrialized country not to join the original pact in 1997 because it did not include other big emitters like China.
Japan insists it would be better to focus on a new treaty by 2015.
"Only developed countries are legally bound by the Kyoto Protocol and their emissions are only 26 percent," Masahiko Horie, speaking for the Japanese delegation, said in Doha. "If we continue the same, only one quarter of the world is legally bound and three quarters of countries are not bound at all."
Related story: Rich-poor split persists at climate talks
But developing countries like Brazil are warning that it will be difficult for poor nations to do their part if they continue watching industrialized nations shy away from legally-binding pacts like Kyoto.
Reuters and The Associated Press contributed to this report.
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