HR: 1330h
AN: H22B-0918    [PDF]
TI: Water Balance of Shrinking Thermkorst Ponds near Council, Alaska
AU: * Fraver, M R
EM: ftmrf@uaf.edu
AF: Water and Environmental Research Center, University of Alaska Fairbanks, PO Box 755860, Fairbanks, AK 99775 United States
AU: Hinzman, L D
EM: ffldh@uaf.edu
AF: Water and Environmental Research Center, University of Alaska Fairbanks, PO Box 755860, Fairbanks, AK 99775 United States
AU: Yoshikawa, K
EM: ffky@uaf.edu
AF: Water and Environmental Research Center, University of Alaska Fairbanks, PO Box 755860, Fairbanks, AK 99775 United States
AU: Kane, D L
EM: ffdlk@uaf.edu
AF: Water and Environmental Research Center, University of Alaska Fairbanks, PO Box 755860, Fairbanks, AK 99775 United States
AB: Water balances were conducted on a wetland complex near Council, Alaska on the Seward Peninsula during the 2001 and 2002 summers in order to investigate the possibility of groundwater drainage through open taliks. This study is a product of the Arctic Transition in the Land-Atmosphere System (ATLAS) initiation within the Land Atmosphere Ice Interactions (LAII) flux program, created to understand the feedbacks within the land-atmosphere system in arctic regions and to predict reasonable scenarios resulting from future global climate change. The majority of ponds in the Council area are displaying a decreased surface area when compared with aerial photographs from the 1950's, and because the long-term temperature and precipitation data from Nome does not reveal any conclusive trends, the cause of this change is hypothesized to be related to the local permafrost and thermokarst conditions. From permafrost boring data, DC electrical sounding studies, and ground penetrating radar (GPR) surveys, the permafrost in the area is typically 20 to 60 meters thick, and underneath the shrinking thermokarst ponds are large thawed regions (taliks), most of which extend through the local permafrost (open taliks). Downward vertical gradients have been identified in the open taliks, indicating the downward migration of water from the ponds to the subpermafrost groundwater. It was hypothesized that this water loss mechanism is significant in the hydrologic dynamics of the ponds and is related to the recent drying of the ponds. The results of this two-year study, however, demonstrate that evapotranspiration and lateral drainage are capable of accounting for 100% of the observed storage changes.
DE: 1818 Evapotranspiration
DE: 1823 Frozen ground
DE: 1829 Groundwater hydrology
DE: 1836 Hydrologic budget (1655)
DE: 1890 Wetlands
SC: Hydrology [H]
MN: 2003 Fall Meeting