HR: 0800h
AN: C11A-0078    [Abstracts]
TI: Atmospheric Conditions Associated With a Significant Greenland Melting Event
AU: * Zhang, S
EM: shunli@atmosp.physics.utoronto.ca
AF: University of Toronto, 60 St. George Street, Toronto, Ont M5S 1A7, Canada
AU: Moore, K
EM: gwk.moore@utoronto.ca
AF: University of Toronto, 60 St. George Street, Toronto, Ont M5S 1A7, Canada
AB: The Greenland melt event in late June 2002 is widely identified as being the most significant melt event, in terms of area extent, that has occurred on the Greenland ice sheet over the period 1979-2003. A mesoscale forecast model (Polar MM5) is used to document the large and regional scale atmospheric circulations that gave rise to this melting event. Model hourly forecasts of downward short wave radiation, 2-m temperature, 10-m wind speed, wind direction, are compared to observations at seventeen Greenland automatic weather stations. The modeled vertical structures of temperature, wind speed and wind direction are verified as well with the sounding data at Aasiaat, Narsarsuaq and Tasiilaq. The model simulation shows a high degree of skill for the basic meteorology variables. Temperature advection and adiabatic heating play are shown to play different roles in southern and northern Greenland. In southern Greenland, the temperature advection resulting from a high-pressure ridge was responsible for the higher temperatures that lead to melting in the region. In contrast, the adiabatic heating resulted from the lee side subsistence was responsible for the abrupt temperature rise and melting over northeastern Greenland. The results provide insight into the atmospheric conditions that result in melting over Greenland.
DE: 0720 Glaciers
DE: 0740 Snowmelt
DE: 1621 Cryospheric change (0776)
DE: 3349 Polar meteorology
SC: Cryosphere [C]
MN: 2007 Fall Meeting