Polar Radiation Budgets of the NCAR CCM3*,+

Abstract
Present-day Arctic and Antarctic radiation budgets of the National Center for Atmospheric Research Community Climate Model version 3 (CCM3) are presented. The CCM3 simulation is from a prescribed and interannually varying sea surface temperature integration from January 1979 through August 1993. Earth Radiation Budget Experiment (ERBE) data from 1985 through 1989 are used for validation of top-of-atmosphere (TOA) absorbed shortwave radiation (ASR) and outgoing longwave radiation (OLR). Summer ASR in both polar regions is less than the observations by about 20 W m−2. While the annual mean OLR in both polar regions is only 2–3 W m−2 less than the ERBE data, the seasonal amplitude in OLR of 40 W m−2 is smaller than the observed of 55–60 W m−2. The annual polar TOA radiation balance is smaller than observations by 5–10 W m−2. Compared to selected model and observational surface data, downward shortwave (SW) is too small by 50–70 W m−2 and downward longwave (LW) too large by 10–30 W m−2. Surface downw... Abstract Present-day Arctic and Antarctic radiation budgets of the National Center for Atmospheric Research Community Climate Model version 3 (CCM3) are presented. The CCM3 simulation is from a prescribed and interannually varying sea surface temperature integration from January 1979 through August 1993. Earth Radiation Budget Experiment (ERBE) data from 1985 through 1989 are used for validation of top-of-atmosphere (TOA) absorbed shortwave radiation (ASR) and outgoing longwave radiation (OLR). Summer ASR in both polar regions is less than the observations by about 20 W m−2. While the annual mean OLR in both polar regions is only 2–3 W m−2 less than the ERBE data, the seasonal amplitude in OLR of 40 W m−2 is smaller than the observed of 55–60 W m−2. The annual polar TOA radiation balance is smaller than observations by 5–10 W m−2. Compared to selected model and observational surface data, downward shortwave (SW) is too small by 50–70 W m−2 and downward longwave (LW) too large by 10–30 W m−2. Surface downw...