In this study, we analyzed the characteristics of summer extreme rainfall over South Korea and their relationships with the synoptic and large-scale circulation anomalies during 1979-2014. Heavy rainfall (R90p) is related with the strong convection surrounded by dry zone over Korean peninsula and the moist air delivered from the convection area over Bay of Bengal-South China Sea-Philippine Sea. The upper-level anticyclonic flow with the low-level dipole of anticyclonic circulation in the Southeast and cyclonic circulation to the northwest of Korean peninsula are the main characteristics when the extreme rainfall occurs. The barotropic Rossby wave developed over the Korean peninsula transfers its energy farther downstream to the western coast of North America. It is also found that the dominant lowfrequency oscillation over the tropics (intraseasonal oscillation) play an important background role for the enhancement of extreme rainfall over South Korea.

This study analyzed the frequency of heatwave occurrences in Jeju Island in summer season (June to September) for the recent 46 years (1968-2013). The frequency showed an increasing trend up until now and we applied statistical change-point analysis in order to determine whether this increasing trend had a climate regime shift. As a result, it was discovered that frequency of heatwave occurrences has rapidly increased since 1990. Thus, to determine the causes of rapid increase in frequency of heatwave occurrences in Jeju Island since 1990, a difference in mean values of June to September between a period of 1990-2013 and a period of 1968-1989 was analyzed. The analysis result of differences between two periods about stream flows showed that large anomalous anticyclonic circulations were strengthened in the subtropical western Pacific and the center of the small anomalous anticyclone, which was branched westwardly out of the anticyclonic circulations was located within the southern part of the Korean Peninsula. This strengthening of the anomalous anticyclone in the Korean Peninsula was also shown at the middle and upper troposphere. The anomalous anticyclonic circulations, which were expanded to the Korean Peninsula from the subtropical western Pacific in recent years was due to strengthening of the western North Pacific subtropical high (WNPSH) in the Korean Peninsula. Hot and humid air can be introduced into the Korean Peninsula due to the strengthening WNPSH in the Korean Peninsula. Furthermore, a difference in daily maximum temperature at 2m height as well as sensible heat net flux between two periods were analyzed in order to determine the degree of the heat at the ground. There was positive anomalies found along the coast in East Asia and the center of the positive anomalies was linked to the Korean Peninsula via the northern part of China. Thus, the Korean Peninsula including Jeju area had more heat than usual in recent years.

MK-PRISM developed for wind interpolation was applied to case studies and was verified in previous studies. Thus, some tests were necessary before the model used in order to produce wind speed maps for the whole area of South Korea. In this study, the MK-PRISM was applied to producing wind speed maps of South Korea. The result showed that sharp changes occur in wind speed distribution, despite the continuous similar topographic. The primary reason for the phenomenon was that a linear regression slope between elevation and wind speed used in interpolation process was changed rapidly in some areas. This study used the landform classification data to address this problem. The improved model controlled similarly the slope of the linear regression equation in the continuous valley, slope, and ridge. Therefore, the slope of the linear regression equation does not change dramatically in the improved model. The improved model was named MK-PRISM-Wind in this study. The wind speed was similar on the ridge continuously in the wind speed distribution produced by MK-PRISM-Wind. In addition, the wind speed was more gradually changed compared to the previous model on the plains and foothills. The results mean that MK-PRISM-Wind can produce wind speed maps more reasonable than the previous model, and it can be applied to the wind speed interpolation of South Korea. High-resolution gridded wind speed map produced by MK-PRISM-Wind is expected to be utilized for various studies.

This study investigated the future change in surface wind over the Korean Peninsula using a high-resolution climate change scenario projected by a regional climate model (RCM). In the evaluation of historical runs (1981-2010), the RCM reasonably reproduced a 30-year annual mean surface wind and it also represented climatological seasonal wind pattern properly. To examine the future change in surface wind, the results from RCP8.5 run for 30 years (2071-2100) were compared with those from historical run. Despite of slight differences among seasons, southerly differences were overall dominant. This indicated that southerly prevailing wind for summer was intensified in the future climate, while northerly prevailing wind for other seasons was reduced. The changes in the seasonal mean surface wind were significantly associated with those in the surface pressure distribution surrounding the Korean Peninsula. In the future climate, the monthly mean wind speed was reduced compared in the present climate. However, the magnitude and annual variability of the annual maximum wind speed tended to increase in the future climate.

The aim of this study is to suggest the social vulnerability index for reflecting social properties of a region, such as population and economy, in vulnerability assessment. For such a research objective, this study composed the assessment index with 'social vulnerability' and 'physical vulnerability'. Also, this study composed the social vulnerability with 'population vulnerability index', 'economic vulnerability index' and 'information vulnerability index' while composing the physical vulnerability with 'flood-risk index', and then selected proxy variables. In addition, this study determined the weight using an entropy weight measurement as an objective weight measurement. The vulnerability assessment result is as follows: First, the vulnerable areas were concentrated around the inner harbours and some rivers of Incheon. Second, the areas vulnerable to the flood caused by climate change were found to be highly vulnerable socially as well as physically. Third, results of assessment were different according to the social properties of an areas despite the identical level of flood risk. The resultant implications are following. First, there is the necessity of having to put emphasis on social vulnerability of an area from the perspective of adaptation to climate change. Second, there is the necessity of having to arrange effective social and physical adaptation strategy based on the results of vulnerability assessment.