HR: 1340h
AN: GC13B-1233    [Abstracts]
TI: Winter Carbon Exchange in the Arctic
AU: * Laskowski, C A
EM: claskowski@ucdavis.edu
AF: San Diego State University Global Change Research Group, 5500 Campanile Dr., San Diego, CA 92182-4614 United States
AU: Oechel, W C
EM: oechel@sciences.sdsu.edu
AF: San Diego State University Global Change Research Group, 5500 Campanile Dr., San Diego, CA 92182-4614 United States
AB: The Arctic, once thought to have the ability to sequester a significant amount of anthropogenic carbon dioxide, is now being viewed as a possible source of carbon to the atmosphere. This is further evidenced as winter measurements become more accessible and reliable. Here, we show that the Arctic exchanges a significant amount of carbon to the atmosphere during the winter (October - March) months. The data are taken from three eddy covariance tower sites along a latitudinal gradient on the North Slope of Alaska, between 1998 and 2005. Results show that, although the daily magnitude of carbon efflux is order(s) of magnitude smaller than summer uptake, the length of the winter season compared to that of the summer season produces a total efflux on the same order of magnitude. High variability between sites and within sites between years demonstrates the complexity of ecosystem respiration even under extreme winter conditions and the need to better resolve climate change models of high-latitude ecosystems.
DE: 1615 Biogeochemical cycles, processes, and modeling (0412, 0414, 0793, 4805, 4912)
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
DE: 1621 Cryospheric change (0776)
DE: 1631 Land/atmosphere interactions (1218, 1843, 3322)
SC: Global Climate Change [GC]
MN: Fall Meeting 2005