Radiative heating rates have been calculated in the region of the Antarctic polar vortex during 1994 using the National Center for Atmospheric Research Community Climate Model (CCM2) radiative transfer model. Temperature and tropospheric water vapor retrievals were used from the high-resolution interferometer sounder (HIS) on board the ER-2 in 1994 to compute clear sky heating rates in April, August, and October. The lower stratospheric heating rate is shown to be sensitive to the skin temperature due to the exchange of radiation within the ozone 9.6 μm band. This implies a coupling between the surface and the lower stratosphere, with the formation of sea ice decreasing the skin temperature and increasing lower stratospheric cooling rates. Computations show weak heating (strong cooling) rates for the fall flight, of the order of -0.7 K/day (potential temperature), with progressively greater heating (smaller cooling) rates associated with the late winter and spring flights and large variations in latitude. HIS temperatures are independent of numerical weather prediction analyses and so provide a useful comparison. Vertical mean (350--420 K) temperature differences between HIS retrievals and collocated U.K. Meteorological Office (UKMO) assimilations are generally within 3 K; HIS temperatures are greater for most flights around and poleward of the vortex edge. Calculated heating rates result in weaker HIS heating (stronger HIS cooling) for most flights resulting from the greater HIS temperatures. Heating rate differences are generally within 0.2 K/day for the 350--420 K vertical mean. The calculations show evidence of a minimum in the cooling rate in the region of the vortex edge for the August and October flights, also seen in the collocated UKMO results as well as in hemispheric calculations. ¿ 1998 American Geophysical Union