Using satellite thermal infrared imagery to study boundary layer structurein an Antarctic katabatic wind region

We use snow surface temperatures obtained from thermal infrared (TIR) satel lite imagery, together with radiosonde profiles of free-air temperature and high-resolution topographic data to study the thermal structure of the atm ospheric boundary layer in a coastal region of East Antarctica. Surface tem peratures over a coastal ice shelf are shown to be significantly lower than those observed on the lower part of the adjoining coastal slopes as a resu lt of the strong surface temperature inversion that forms over the ice shel f. Between 400 and 1500 m elevation the surface temperature lapse rate is c lose to the dry adiabatic value while the free-air temperature profile is s ignificantly stable over this height range. We argue that this implies that the strength of the surface inversion increases with increasing elevation. Above 1500 m the surface temperature lapse rate becomes significantly supe radiabatic and the coldest surface temperatures are found a few 10s of kilo metres inland of the highest topography. The technique may prove useful for studying boundary layer structure in other regions of Antarctica where sui table high-resolution topographic data are available.