THE ENERGY-BALANCE OF SNOW AND PARTIALLY SNOW COVERED AREAS IN WESTERN GREENLAND

Surface meteorology and flux data are presented from five sites in a t ransect crossing a 100-km-wide coastal region of west Greenland. The s ites cover a variety of Arctic types: snow covered, bog and arid. The measurements show a comparatively small variation of the driving varia bles: solar radiation, wind and humidity, but a large variation in the net radiation and surface fluxes. The net radiation is much reduced i n the snow covered areas because of the high albedo, ameliorated to so me extent by a reduced longwave emission. The turbulent fluxes are als o small over the snow covered areas, an effect of the smooth surface a nd low surface temperature. The sensible heat flux at these sites is d ownward. The evaporation fluxes in the snow-free areas are strongly af fected by the availability of soil-water, thus in the arid, eastern si te the evaporation is small. Simple flux-gradient equations appear to be able to describe the surface fluxes adequately, especially consider ing the comparatively large error in these types of data. The relevanc e of these data to the parameterization of Arctic surfaces in global m odels is discussed.