Atmospheric heat budgets of the polar regions


  • Noboru Nakamura,

  • Abraham H. Oort


The energy budget and its annual variation are studied for the polar regions of the atmosphere. Composite satellite and rawinsonde data are used to compute the rate of storage of energy in the atmosphere, the net radiation flux at the top of the atmosphere, and the energy fluxes across 70°N and 70°S, while the energy flux across the Earth's surface is estimated as a residual. Data produced by a general circulation model are used to obtain plausible estimates of the energy flux across 70°S, where direct estimates tend to be poor. We find that the heat exchange between the atmosphere and the ocean-cryosphere system plays a much larger role in the Arctic than in the Antarctic polar cap. When the polar caps are extended from 70° to 60° latitude, both the land-sea distributions and the different terms balancing the energy budgets become more comparable between the two regions.