Science Current Events | Science News |

Most of Arctic's Near-Surface Permafrost May Thaw by 2100

December 20, 2005
BOULDER-Global warming may decimate the top 10 feet (3 meters) or more of perennially frozen soil across the Northern Hemisphere, altering ecosystems as well as damaging buildings and roads across Canada, Alaska, and Russia. New simulations from the National Center for Atmospheric Research (NCAR) show that over half of the area covered by this topmost layer of permafrost could thaw by 2050 and as much as 90 percent by 2100. Scientists expect the thawing to increase runoff to the Arctic Ocean and release vast amounts of carbon into the atmosphere.

The study, using the NCAR-based Community Climate System Model (CCSM), is the first to examine the state of permafrost in a global model that includes interactions among the atmosphere, ocean, land, and sea ice as well as a soil model that depicts freezing and thawing. Results appear online in the December 17 issue of Geophysical Research Letters.

"People have used models to study permafrost before, but not within a fully interactive climate system model," says NCAR's David Lawrence, the lead author. The coauthor is Andrew Slater of the University of Colorado's National Snow and Ice Data Center.

About a quarter of the Northern Hemisphere's land contains permafrost, defined as soil that remains below 32 degrees F (0 degrees C) for at least two years. Permafrost is typically characterized by an active surface layer, extending anywhere from a few centimeters to several meters deep, which thaws during the summer and refreezes during the winter. The deeper permafrost layer remains frozen. The active layer responds to changes in climate, expanding downward as surface air temperatures rise. Deeper permafrost has not thawed since the last ice age, over 10,000 years ago, and will be largely unaffected by global warming in the coming century, says Lawrence.

Recent warming has degraded large sections of permafrost across central Alaska, with pockets of soil collapsing as the ice within it melts. The results include buckled highways, destabilized houses, and "drunken forests"-trees that lean at wild angles. In Siberia, some industrial facilities have reported significant damage. Further loss of permafrost could threaten migration patterns of animals such as reindeer and caribou.

The CCSM simulations are based on high and low projections of greenhouse-gas emissions for the 21st century, as constructed by the Intergovernmental Panel on Climate Change. In both cases, the CCSM determined which land areas would retain permafrost at each of 10 soil depths extending down to 11.2 feet (3.43 meters).

For the high-emission scenario, the area with permafrost in any of these layers shrinks from 4 million to just over 1 million square miles by the year 2050 and decreases further to about 400,000 square miles (1 million square kilometers) by 2100. In the low-emission scenario, which assumes major advances in conservation and alternative energy, the permafrost area shrinks to about 1.5 million square miles by 2100.

"Thawing permafrost could send considerable amounts of water to the oceans," says Slater, who notes that runoff to the Arctic has increased about 7 percent since the 1930s. In the high-emission simulation, runoff grows by another 28 percent by the year 2100. That increase includes contributions from enhanced rainfall and snowfall as well as the water from ice melting within soil.

The new study highlights concern about emissions of greenhouse gases from thawing soils. Permafrost may hold 30% or more of all the carbon stored in soils worldwide. As the permafrost thaws, it could lead to large-scale emissions of methane or carbon dioxide beyond those produced by fossil fuels.

"There's a lot of carbon stored in the soil," says Lawrence. "If the permafrost does thaw, as our model predicts, it could have a major influence on climate." To address this and other questions, Lawrence and colleagues are now working to develop a more advanced model with interactive carbon.

This study was funded by the National Science Foundation, which is NCAR'S primary sponsor, and the U.S. Department of Energy.

The National Snow and Ice Data Center (NSIDC) is part of the Cooperative Institute for Research in Environmental Sciences at the University of Colorado. Visit the NSIDC Web site.

National Center for Atmospheric Research

Related Permafrost Current Events and Permafrost News Articles

Certain Arctic lakes store more greenhouse gases than they release
New research, supported by the National Science Foundation (NSF), counters a widely-held scientific view that thawing permafrost uniformly accelerates atmospheric warming, indicating instead that certain Arctic lakes store more greenhouse gases than they emit into the atmosphere.

Huge waves measured for first time in Arctic Ocean
As the climate warms and sea ice retreats, the North is changing. An ice-covered expanse now has a season of increasingly open water that is predicted to extend across the whole Arctic Ocean before the middle of this century.

Wetlands Likely to Blame for Greenhouse Gas Increases: Study
A surprising recent rise in atmospheric methane likely stems from wetland emissions, suggesting that much more of the potent greenhouse gas will be pumped into the atmosphere as northern wetlands continue to thaw and tropical ones to warm, according to a new international study led by a University of Guelph researcher.

Researchers Find 3-million-year-old Landscape Beneath Greenland Ice Sheet
Glaciers and ice sheets are commonly thought to work like a belt sander. As they move over the land they scrape off everything - vegetation, soil and even the top layer of bedrock.

Methane climate change risk suggested by proof of redox cycling of humic substances
The recent Yokahama IPCC meeting painted a stark warning on the possible effects of gases such as methane - which has a greenhouse effect 32 times that of carbon dioxide.

Researchers: Permafrost thawing could accelerate global warming
A team of researchers lead by Florida State University have found new evidence that permafrost thawing is releasing large quantities of greenhouse gases into the atmosphere via plants, which could accelerate warming trends.

Permafrost Thaw Exacerbates Climate Change
The climate is warming in the arctic at twice the rate of the rest of the globe creating a longer growing season and increased plant growth, which captures atmospheric carbon, and thawing permafrost, which releases carbon into the atmosphere.

A tale of 2 data sets: New DNA analysis strategy helps researchers cut through the dirt
For soil microbiology, it is the best of times. While no one has undertaken an accurate census, a spoonful of soil holds hundreds of billions of microbial cells, encompassing thousands of species.

Arctic biodiversity under serious threat from climate change according to new report
Unique and irreplaceable Arctic wildlife and landscapes are crucially at risk due to global warming caused by human activities according to the Arctic Biodiversity Assessment (ABA), a new report prepared by 253 scientists from 15 countries under the auspices of the Conservation of Arctic Flora and Fauna (CAFF), the biodiversity working group of the Arctic Council.

A 'smoking gun' on the Ice Age megafauna extinctions
It was climate that killed many of the large mammals after the latest Ice Age. But what more specifically was it with the climate that led to this mass extinction?
More Permafrost Current Events and Permafrost News Articles

Permafrost: A guide to Frozen Ground in Transition

Permafrost: A guide to Frozen Ground in Transition
by Neil Davis (Author)

Overall, this is an outstanding introductory book on seasonally frozen ground and permafrost for a broad audience. It is also an excellent reference book for students, permafrost scientists and engineers, and professionals in earth and environmental sciences. It provides a valuable orientation to motivate students who are contemplating careers in permafrost studies. It also appeals to social scientists and environmentalists studying northern regions and the effects of permafrost on society as a whole. Furthermore, this volume is well printed and illustrated.

Neil Davis brings his unusual talent for communicating scientific concepts in an engaging and readable style to the topic of permafrost, the process of annual freezing and thawing that covers half of the land in the...


by Solstice Shadows

Cyan had taken the colony position in hopes to start a new life. Instead, the planet was as empty and desolate as her dad predicted her future as a scientist would be.
Until the morning she saw the bird. In a flurry of feathers, she went from the base nobody to instant celebrity. The one to find life where none was before.
But can they find where the bird came from, and come back, before the colony is abandoned?


by Peter Robertson (Author)

Two friends grew up together in Scotland. Now one is missing in Northern Michigan and the other, a successful businessman, has time on his hands. The hunt for the lost man begins as a mystery and evolves into an act of redemption.

Permafrost Foundations: State of the Practice

Permafrost Foundations: State of the Practice
by Edwin S. Clarke (Editor)

As building expands in the northern latitudes, it is critical to get information about soil conditions and geotechnical and structural issues in the hands of those dealing with the many challenges of building on frozen soils. Permafrost Foundations: State of the Practice presents the most current techniques used to design and construct foundations on permafrost. Failure to understand the complexity of technical issues involved in building under these extreme conditions can start with the settlement or jacking of the soils, and result in conditions ranging from sloping buildings to swayback roofs to complete structural collapse. This monograph includes eight chapters, which present the authors experiences in both the design and remedial actions required for the continued successful...

Permafrost Soils (Soil Biology)

Permafrost Soils (Soil Biology)
by Rosa Margesin (Editor)

Most of the Earth’s biosphere is characterized by low temperatures. Vast areas (>20%) of the soil ecosystem are permanently frozen or are unfrozen for only a few weeks in summer. Permafrost regions occur at high latitudes and also at high ele- tions; a significant part of the global permafrost area is represented by mountains. Permafrost soils are of global interest, since a significant increase in temperature is predicted for polar regions. Global warming will have a great impact on these soils, especially in northern regions, since they contain large amounts of organic carbon and act as carbon sinks, and a temperature increase will result in a release of carbon into the atmosphere. Additionally, the intensified release of the clima- relevant tracer gas methane represents a potential...

PERMAFROST. Fourth International Conference. Final Proceedings July 17 - 22, 1983.

PERMAFROST. Fourth International Conference. Final Proceedings July 17 - 22, 1983.
by (National Academy) (Author)

Permafrost Hydrology

Permafrost Hydrology
by Ming-ko Woo (Author)

Permafrost Hydrology systematically elucidates the roles of seasonally and perennially frozen ground on the distribution, storage and flow of water. Cold regions of the World are subject to mounting development which significantly affects the physical environment. Climate change, natural or human-induced, reinforces the impacts. Knowledge of surface and ground water processes operating in permafrost terrain is fundamental to planning, management and conservation. This book is an indispensable reference for libraries and researchers, an information source for practitioners, and a valuable text for training the next generations of cold region scientists and engineers.

  Permafrost: Engineering Design and Construction
by G. Henry Johnston (Editor)

Permafrost Ecosystems: Siberian Larch Forests (Ecological Studies)

Permafrost Ecosystems: Siberian Larch Forests (Ecological Studies)
by Akira Osawa (Editor), Olga A. Zyryanova (Editor), Yojiro Matsuura (Editor), Takuya Kajimoto (Editor), Ross W. Wein (Editor)

Drawing from a decade-long collaboration between Japan and Russia, this important volume presents the first major synthesis of current knowledge on the ecophysiology of the coniferous forests growing on permafrost at high latitudes. It presents ecological data for a region long inaccessible to most scientists, and raises important questions about the global carbon balance as these systems are affected by the changing climate. Making up around 20% of the entire boreal forests of the northern hemisphere, these ‘permafrost forest ecosystems’ are subject to particular constraints in terms of temperature, nutrient availability, and root space, creating exceptional ecosystem characteristics not known elsewhere. This authoritative text explores their diversity, structure, dynamics and...

Opportunities to Use Remote Sensing in Understanding Permafrost and Related Ecological Characteristics: Report of a Workshop

Opportunities to Use Remote Sensing in Understanding Permafrost and Related Ecological Characteristics: Report of a Workshop
by Committee on Opportunities to Use Remote Sensing in Understanding Permafrost and Ecosystems: A Workshop (Author), Polar Research Board (Author), Division on Earth and Life Studies (Author), National Research Council (Author)

Permafrost is a thermal condition -- its formation, persistence and disappearance are highly dependent on climate. General circulation models predict that, for a doubling of atmospheric concentrations of carbon dioxide, mean annual air temperatures may rise up to several degrees over much of the Arctic. In the discontinuous permafrost region, where ground temperatures are within 1-2 degrees of thawing, permafrost will likely ultimately disappear as a result of ground thermal changes associated with global climate warming. Where ground ice contents are high, permafrost degradation will have associated physical impacts. Permafrost thaw stands to have wide-ranging impacts, such as the draining and drying of the tundra, erosion of riverbanks and coastline, and destabilization of...

© 2014