Surface Energy Balance at Sejong Station, King George Island, Antarctica

This study examines seasonal variability of the surface energy balance at the King Sejong Station, Antarctica, using measurements and estimates of the components related to the balance for the period of 1996 to 2004. Annual average of downward shortwave radiation at the surface is 81 Wm(-2) which is 37% of the extraterrestrial value, with the monthly maximum of 188 Wm(-2) in December and the minimum of 8 Wm(-2) in June. These values are relatively smaller than those at other stations in Antarctica, which can be attributed to higher cloudy weather conditions in Antarctic front zone. Surface albedo varies between similar to 0.3 in the austral summer season and similar to 0.6 in the winter season. As a result, the net shortwave radiation ranges from 117 Wm(-2) down to 3 Wm(-2) with annual averages of 43 Wm(-2). Annual average of the downward longwave radiation shows 278 Wm(-2), ranging from 263 Wm(-2) in August to 298 Wm(-2) in January. The downward longwave radiation is verified to be dependent strongly on the air temperature and specific humidity, accounting for 74% and 79% of the total variance in the longwave radiation, respectively. The net longwave radiation varies between 25 Wm(-2) and 40 Wm(-2) with the annual averages of 30 Wm(-2). Accordingly, the annual average energy balance is dominated by radiative warming of a positive net all-wave radiation from September to next March and radiative cooling of a negative net all-wave radiation from April to August. The net all-wave radiative energy gain and loss at the surface is mostly balanced by turbulent flux of sensible and latent heat. The soil heat flux is of negligible importance in the surface energy balance.