Greenhouse gas bubbling from melting permafrost feeds climate warming

September 06, 2006

TALLAHASSEE, Fla. -- A study co-authored by a Florida State University scientist and published in the Sept. 7 issue of the journal Nature has found that as the permafrost melts in North Siberia due to climate change, carbon sequestered and buried there since the Pleistocene era is bubbling up to the surface of Siberian thaw lakes and into the atmosphere as methane, a greenhouse gas 20 times more potent than carbon dioxide.

In turn, that bubbling methane held captive as carbon under the permafrost for more than 40,000 years is accelerating global warming by heating the Earth even more --- exacerbating the entire cycle. The ominous implications of the process grow as the permafrost decomposes further and the resulting lakes continue to expand, according to FSU oceanography Professor Jeff Chanton and study co-authors at the University of Alaska-Fairbanks.

"This is not good for the quality of human life on Earth," Chanton said.

The researchers devised a novel method of measuring ebullition (bubbling) to more accurately quantify the methane emissions from two Siberian thaw lakes and in so doing, revealed the world's northern wetlands as a much larger source of methane release into the atmosphere than previously believed. The magnitude of their findings has increased estimates of such emissions by 10 to 63 percent.

Understanding the contribution of North Siberia thaw lakes to global atmospheric methane is critical, explains the paper that appears in this week's Nature, because the concentration of that potent greenhouse is highest at that latitude, has risen sharply in recent decades and exhibits a significant seasonal jump at those high northern latitudes.

Chanton points to the thawing permafrost along the margins of the thaw lakes -- which comprise 90 percent of the lakes in the Russian permafrost zone -- as the primary source of methane released in the region. During the yearlong study, he performed the isotopic analysis and interpretation to determine the methane's age and origin and assisted with measurements of the methane bubbles' composition to shed light on the mode of gas transport.

"My fellow researchers and I estimate that an expansion of these thaw lakes between 1974 and 2000, a period of regional warming, increased methane emissions by 58 percent there," said Chanton. "Because the methane now emitted in our study region dates to the Pleistocene age, it's clear that the process, described by scientists as 'positive feedback to global warming,' has led to the release of old carbon stocks once stored in the permafrost."
-end-
In addition to Chanton, the John Widmer Winchester Professor of Oceanography at FSU, co-authors of "Methane bubbling from Siberian thaw lakes as a positive feedback to climate warming" include K. M. Walter (Institute of Arctic Biology, University of Alaska-Fairbanks); S. A. Zimov (Northeast Science Station, Cherskii, Russia); and D. Verbyla (Forest Science department, University of Alaska-Fairbanks).

For more stories about FSU, visit our news site at www.fsu.com

Florida State University

Related Climate Change Articles from Brightsurf:

Are climate scientists being too cautious when linking extreme weather to climate change?
Climate science has focused on avoiding false alarms when linking extreme events to climate change.

Mysterious climate change
New research findings underline the crucial role that sea ice throughout the Southern Ocean played for atmospheric CO2 in times of rapid climate change in the past.

Mapping the path of climate change
Predicting a major transition, such as climate change, is extremely difficult, but the probabilistic framework developed by the authors is the first step in identifying the path between a shift in two environmental states.

Small change for climate change: Time to increase research funding to save the world
A new study shows that there is a huge disproportion in the level of funding for social science research into the greatest challenge in combating global warming -- how to get individuals and societies to overcome ingrained human habits to make the changes necessary to mitigate climate change.

Sub-national 'climate clubs' could offer key to combating climate change
'Climate clubs' offering membership for sub-national states, in addition to just countries, could speed up progress towards a globally harmonized climate change policy, which in turn offers a way to achieve stronger climate policies in all countries.

Review of Chinese atmospheric science research over the past 70 years: Climate and climate change
Over the past 70 years since the foundation of the People's Republic of China, Chinese scientists have made great contributions to various fields in the research of atmospheric sciences, which attracted worldwide attention.

A CERN for climate change
In a Perspective article appearing in this week's Proceedings of the National Academy of Sciences, Tim Palmer (Oxford University), and Bjorn Stevens (Max Planck Society), critically reflect on the present state of Earth system modelling.

Fairy-wrens change breeding habits to cope with climate change
Warmer temperatures linked to climate change are having a big impact on the breeding habits of one of Australia's most recognisable bird species, according to researchers at The Australian National University (ANU).

Believing in climate change doesn't mean you are preparing for climate change, study finds
Notre Dame researchers found that although coastal homeowners may perceive a worsening of climate change-related hazards, these attitudes are largely unrelated to a homeowner's expectations of actual home damage.

Older forests resist change -- climate change, that is
Older forests in eastern North America are less vulnerable to climate change than younger forests, particularly for carbon storage, timber production, and biodiversity, new research finds.

Read More: Climate Change News and Climate Change Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.