The geographical distributions of CDDs and HDDs in South Korea for the period 2000~2009 with 2050~2059 are studied by using daily mean temperature data with 1 km horizontal resolution estimated by MK (Modified Korean)-PRISM (Parameter-elevation Regressions an Independent Slopes\ Model) driven by the IPCC (Intergovernmental Panel on Climate Change) RCP (Representative Concentration Pathways)2.6/8.5. The HDD amounts in winter season decrease, declining from north to south and from the high mountain area to the coastal area. In summer season, the higher fuel consumption appears in urban areas, with much higher CDD amounts and for a longer period of time. In the mid-century under RCP2.6 (RCP8.5), HDDs are projected to decrease by 13% (16%) while CDDs are likely to increase by 36% (51%). The total length of cooling (heating) period in Korea is projected to increase (decrease) due to the advance (delay) of the beginning date and the delay (advance) of the end date. These results suggest that special attention should be paid to space cooling, since the cooling demand is expected to grow rapidly in most regions except for mountainous areas. The projection of future CDDs and HDDs will be useful for various energy projects and other environmental applications.

Characteristics of urban warming phenomenon were studied using degree days for three big cities(Seoul, Busan, Daegu) adjacent to airport. Time variation of the cooling and heating degree days was analyzed using the daily mean air temperature data measured at the six meteorological observatory for long-term periods(25～43years). The results for the big cities are as followings: 1) It was found that the heating degree days trended to decrease from year to year. 2) The cooling degree days were nearly unchanged during the same analysis periods. 3) The number of days calling for air-heating also tended to decrease as time passes. 4) Those of air-cooling were nearly unchanged during the same time. It suggests that the change of air-heating condition owing to urbanization came in evidence in the winter season, but that of air-cooling condition was slight in the summer season. On the other hand, the long-term trends of degree days were very small in airport areas except for Kimhae airport. Hence, the gaps of degree days between big cities and rural airport areas are increasing.