text-only page produced automatically by LIFT Text Transcoder Skip all navigation and go to page contentSkip top navigation and go to directorate navigationSkip top navigation and go to page navigation
National Science Foundation
News
design element
News
News From the Field
For the News Media
Special Reports
Research Overviews
NSF-Wide Investments
Speeches & Lectures
NSF Current Newsletter
Multimedia Gallery
News Archive
News by Research Area
Arctic & Antarctic
Astronomy & Space
Biology
Chemistry & Materials
Computing
Earth & Environment
Education
Engineering
Mathematics
Nanoscience
People & Society
Physics
 

Email this pagePrint this page
All Images


Press Release 09-111
Arctic Tundra May Contribute to Warmer World

Researchers predict permafrost thaw will intensify climate change

Back to article | Note about images

As areas with permafrost thaw and more old carbon is released, the carbon balance changes.

A lot of old carbon is stored deep in the tundra where it is locked in permafrost. As these areas start to thaw over about 15 years, large ice wedges in the soil get smaller causing pot-holing and soil depression. The newly available water prompts faster plant growth, and the carbon taken out of the atmosphere by the plants photosynthesizing is greater than the carbon released back into the atmosphere by plants respiring and microbes decomposing carbon. However, after about 50 years, as thawing continues and the soil settles even more, plants are growing faster yet, however the rate of plant respiration and old carbon release through microbes grows even bigger netting more carbon out into the atmosphere than into the soil.

Credit: Zina Deretsky, National Science Foundation


Download the high-resolution JPG version of the image. (595 KB)

Use your mouse to right-click (Mac users may need to Ctrl-click) the link above and choose the option that will save the file or target to your computer.

Photo of researcher in a field and the words Audio Slideshow

To start the audio slideshow, click on the screen or on the play arrow in the lower left. Alternatively, you can navigate with the arrow keys or view the whole set of pictures at once using the buttons in the lower right.

Credit: Ted Schuur, University of Florida

 

Ecologist Ted Schuur from the University of Florida describes how his research team used radiocarbon dating, a technique typically used to determine the age of artifacts, to measure the movement of 'old' organic carbon within Alaskan permafrost. From 2004 to 2006, Schuur and his team used radiocarbon dating to track current metabolism of old carbon in an area where permafrost thaw is increasing.

Credit: University of Florida and National Science Foundation

 

Ted Schuur, an ecologist at the University of Florida, describes the Alaskan site where he and colleagues carried out the research described in a recent article in the journal Nature. The site monitored over the past two decades, with permafrost temperature measurements beginning before the permafrost began to thaw. This detailed record coupled with Schuur's study of ecosystem carbon exchange and old carbon release provide a comprehensive picture of the dynamics of carbon exchange in response to permafrost thaw.

Credit: University of Florida and National Science Foundation

 

University of Florida's Ted Schuur, discusses his research, which documents the long-term plant and soil changes that occur as permafrost thaws, thus providing a basis for making long term predictions about ecosystem carbon balance with increased confidence. The study, published in the May 28 issue of the journal Nature has helped define the potentially significant contribution of permafrost thaw to atmospheric concentrations of carbon, which have already reached unprecedented levels.

Credit: University of Florida and National Science Foundation

 

Illustration showing the carbon cycle.

Carbon is stored in the atmosphere, vegetation, soil, deep layers of the crust and in surface and deep water. A few of the mechanisms of bringing carbon into the system are plants photosynthesizing, and storms carrying sediment down into the ocean. Decomposition by fungi and bacteria, plants and animals respiring, burning fossil fuels and carbon dioxide dissolving off of the ocean are some of the mechanisms that release carbon back out.

Credit: Zina Deretsky, National Science Foundation


Download the high-resolution JPG version of the image. (578 KB)

Use your mouse to right-click (Mac users may need to Ctrl-click) the link above and choose the option that will save the file or target to your computer.

Photo of the Alaskan permafrost research site.

Twice as much carbon is contained in the soils and permafrost of northern ecosystems compared to the atmosphere. Because of the size and nature of the permafrost carbon pool, decomposition of previously frozen, old organic carbon is one of the most likely positive feedbacks to climate change in a warmer world. Under the direction of Ted Schuur of the University of Florida, this research used radiocarbon dating to detect the loss of old soil carbon in combination with an ecosystem-scale field manipulation to study factors that affect the release of permafrost carbon. These measurements helped quantify the lateral movement of carbon from tundra ecosystems experiencing permafrost thaw, allowing researchers to estimate the overall loss of carbon from these ecosystems.

Credit: Ted Schuur


Download the high-resolution JPG version of the image. (3.8 MB)

Use your mouse to right-click (Mac users may need to Ctrl-click) the link above and choose the option that will save the file or target to your computer.



Email this pagePrint this page
Back to Top of page