HR: 11:50h
AN: H52B-07    [Abstracts]
TI: Land-atmosphere interactions in the 2003 European heatwave: comparing observations from an extreme event with RCM predictions for future climate
AU: * Zaitchik, B F
EM: benjamin.zaitchik@yale.edu
AF: Department of Geology and Geophysics, Yale University PO Box 208109, New Haven, CT 06520-8109 United States
AU: Macalady, A K
EM: alison.macalady@yale.edu
AF: Yale School of Forestry & Environmental Studies, 205 Prospect Street, New Haven, CT 06511 United States
AU: Bonneau, L R
EM: laurent.bonneau@yale.edu
AF: Yale Center For Earth Observation, Yale University PO Box 208109, New Haven, CT 06520-8109 United States
AU: Smith, R B
EM: ronald.smith@yale.edu
AF: Department of Geology and Geophysics, Yale University PO Box 208109, New Haven, CT 06520-8109 United States
AB: We use a combination of satellite imagery, meteorological station data, and the NCEP/NCAR reanalysis to explore the spatial and temporal evolution of the 2003 heatwave in France, with a focus on understanding impacts to vegetation and energy fluxes at the land surface. Vegetation was severely affected across the study area, especially in a swath across central France that corresponds to the Western European Broadleaf Forests ecological zone (WEB). The remotely sensed surface temperature anomaly was also greatest in this zone, peaking at +15.4 ° C in August. At a finer spatial scale, both the vegetation and surface temperature anomalies were greater for crops and pastures than for forested lands. The heatwave was also associated with an anomalous surface forcing of air temperature. Relative to other years in the record, satellite-derived estimates of surface sensible heat flux indicate an enhancement of 48-61% (24.0-30.5 W m^-2) in WEB during the August heatwave maximum. Longwave radiative heating of the planetary boundary layer was enhanced by 10.5 W m^-2 in WEB for the same period. The magnitude and spatial structure of this local heating is consistent with models of the late-21st century climate in France, which predict a transitional climate zone that will become increasingly affected by summertime drought. Models of future climate also suggest that a soil-moisture feedback on the surface energy balance might exacerbate summertime drought, and we test proposed feedback mechanisms using satellite-derived heat budgets.
UR: http://www.yale.edu/ceo/Projects/Faculty/EU_Drought.html
DE: 0480 Remote sensing
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
DE: 1637 Regional climate change
DE: 1812 Drought
DE: 3322 Land/atmosphere interactions (1218, 1631, 1843)
SC: Hydrology [H]
MN: Fall Meeting 2005