An analysis is presented of possible changes in the radiative terms of the Polar Ocean energy budget. Theoretical polar atmospheres are discussed with various changes in the radiation balance. It is concluded that the atmosphere is, at present, adjusted in the best possible way for the conservation of energy. Radiation budgets are presented, for various assumed conditions. The optimum surface conditions would occur with winter overcast and summer clear sky. The earth-atmosphere radiation budget is presented for an open Polar Ocean. Relatively minor variations in any term can result in a complete freeze-over or complete melting. The atmospheric advection required with an open Polar Ocean would decrease significantly from the present. It might even become, in winter, a heat export from the Polar Ocean.