Surface Energy Balance on the Arctic Tundra: Measurements and Models
A. H. Lynch , F. S. Chapin III , L.D. Hinzman , W.Wu1, E. Lilly, G. Vourlitis , E. Kim
Abstract
The progress made in the Land-Atmosphere-Ice Interactions (LAII) Flux Study over the past four years to fully characterize the biophysical fluxes in the snow-free tundra ecosystem and their relationship to climate and climate change is presented. In the past, for many climate applications, it has been deemed sufficient to provide some generalized lower boundary condition (e.g. temporally and spatially varying temperature, albedo and surface fluxes) and to treat the land surface and vegetation as a constant. Similarly, in studies of the ecosystem, permafrost and soil hydrology, the climate is customarily treated as an independent variable. However, interest in the processes occurring in the land surface-vegetation system itself, and the need to characterize the feedback mechanisms between this system and others (atmosphere, glaciers, coastal processes and ocean), has led to increased interest in the dynamic interactions between land surface and climate. This paper presents the results of a synthesis effort to bring together the measurements of surface fluxes at various sites on the North Slope of Alaska in the snow free period of 1995 with the results of modeling efforts for this region. Issues addressed in particular include the sensitivity of conclusions regarding the relationship between vegetation type and surface energy balance to measurement technique; the sensitivity of the atmospheric circulation to vegetation characteristics; and the significance of regional scale areal mean surface fluxes.