Land-atmosphere carbon fluxes along a thaw-lake chronosequence on the Arctic Coastal Plain of Alaska and Seasonal and inter-annual controls on carbon dioxide and methane flux in Arctic Alaska.
Flooded and vegetated thaw lake basins are common features in permafrost zones and cover a large portion of the land surface. Thaw lakes on the Arctic Coastal Plain of Alaska have been continually formed and lost starting approximately 10,000 years ago, when the climate was warmer and wetter than today. Recent changes in the extent of thaw lakes are believed to be the result of global warming, but the overall patterns of change in continuous permafrost zones, like the Arctic Coastal Plain, are still unclear. However, these systems represent vast stores of non-decomposed organic material (approximately 50% of all below-ground carbon globally), leading to great concern that should they begin to decompose more rapidly due to global warming, this could release unprecedented amounts of greenhouse gasses into the atmosphere. Using a collage of variously aged thaw lakes, Dr. Oechel is studying how long-term ecosystem changes can alter the carbon balance of the tundra ecosystem and impact the releases of carbon dioxide and methane.
Separately, in collaboration with from Florida International University and the University of Texas El Paso, Dr. Oechel has created a large-scale water table manipulation in these thaw lake basins near Barrow, Alaska, to mimic different scenarios that are expected to be created by global warming. He has also established long-term research sites at Atqasuk and Ivotuk, creating a 300 km (185 mile) transect from the northern-most point of Alaska south to the foothills of the Brooks Range, and covering the three most common vegetation communities found in the Arctic. Dr. Oechel is studying how these changes in water availability in Barrow, and differences in vegetation communities across the North Slope of Alaska, interact with changes in temperature and other factors due to the different seasons and variability in year to year weather to control the uptake and release the carbon dioxide and methane, two of the most important greenhouse gasses.
For more information or to join this internship please contact Dr Walter Oechel