대기 및 해양의 대규모 환경에서 열대저기압 발생의 잠재적 빈도는 잠재생성지수(GPI; Genesis Potential Index)를 이용하여 예측할 수 있다. 본 연구에서는 18개의 CMIP5 기후모델을 이용하여 GPI의 연진동 및 경년변동성이 분석되었다. 비교를 위하여 재분석자료로부터 계산된 GPI의 연진동이 재조명되었다. 특히 CMIP5 기후모델과 재분석자료에 의한 GPI가 비교되었고, 그 차이에 대한 가능한 해석이 논의되었다. ENSO (El Nino and Southern Oscillation)는 열대 저기압 발생 및 경로에 영향을 주는 열대 기후현상이다. 잠재생성지수가 네 개의 대규모 매개변수의 함수임을 이용함으로써 열대저기압발생에 대한 역학적 해석이 제시되었다. 본 연구에서는 엘니뇨 혹은 라니냐 해에 GPI 편차를 논의하였고, 그 편차에 가장 영향을 많이 주는 인자를 찾았다. 또한 여러 대규모 인자를 활용하여 북태평양지역 열대저기압 발생에 대하여 가능한 기작을 논의하였다.
We examined the ocean forcing, associated with the different trends in precipitation between North and South Korea, using GPCC V2018 precipitation and OISST V2 sea surface temperature (SST) for the recent thirty years of 1982-2011. As a result of linear regression, the precipitation trends in the monsoon (June and July) and post-monsoon (August and September) seasons were different between North and South Korea, respectively, with increased and decreased trends, during the both monsoon seasons. During the monsoon season, the results of detrended correlation and composite analysis showed the opposite relationships of precipitation with SSTs in the equatorial Pacific and Arctic Oceans between North and South Korea. It was identified that large-scale atmospheric circulation linked to ENSO can differently affect the Korean Peninsula. On the other hand, during the post-monsoon season, the correlation and composite patterns across the oceans in the Northern Hemisphere were generally similar for the two Koreas. It was suggested that near the ocean of the Korean Peninsula and the land surface forcings might affect the precipitation variability during the post-monsoon season, especially in North Korea.
본 연구에서는 국내 기상관측소 중 관측년수가 30년 이상인 관측소 63개 지점에 대한 5개의 수문기상수문인자 즉, 연강수량, 연강수일수, 연평균기온, 연평균상대습도, 연일조시간 자료를 각 지점별로 수집하고, 통계학적 기법인 Wald-Wolfowitz 검정, Mann-Whitney 검정을 이용하여 변동성 분석과 Wavelet Transform을 이용하여 주기성을 분석하였다. 변동성 분석결과 연평균상대습도, 연평균기온에서 공통적으로 변동성이 나타났으며, 연
본 연구에서는 하상이 경년별로 변화함에 따라 발생되는 수위-유량 관계곡선의 오차를 보완하기 위해 최근(2006 년)의 수위-유량 관계곡선을 기준으로 채택하여 일원화시키고, 과거의 하상상태와 경년별로 작성되어 왔던 수위-유량 관계곡선들과의 관계 및 수위, 단면적, 유속 등에 대한 수리기하학적 특성을 분석하였다. 연구 대상지점으로는 낙동강의 주요지점인 적포교와 진동 지점을 택하였으며, 과거의 실측 유량값을 최근(2006년)하에서의 유량으로 환산하였을 때 얻
The aim of the present study is to investigate the interannual variabilities of the East Asia monsoon rainfall associated with the global sea surface temperature anomaly(SSTA). For this study, the summer rainfall(from June to August) over the twenty-eight period of 1961-1988 were analyzed with being divided by nine-subregions over East Asia including Korea, China and Japan. From the analysis of the principal modes explaining the interannual variation, the interannual variabilities of summer rainfalls in South Japan and Korea are larger than those of the other subregions of the East Asia. There is a strong negative correlation between the summer rainfalls of south China and Korea. In this study, the relationship between the summer monsoon of each subregion and SSTs of the tropical NINO regions, of western Pacific warm pool, and of the subtropical ocean were investigated. The longitudinal sections of the lagged cross correlations of the summer rainfall anomaly in (a) Korea and (b) south China, and the monthly SSTA in the equatorial (averaged from 6S to 6N) Pacific were analyzed. The negative maximum correlation pattern of Korea`s summer rainfall and SSTs over the eastern Pacific is transfered to positive maximum correlation over central Pacific region with a biennial periodicity. In South China, the significant positive correlations are found at -12 month lag over the eastern Pacific and maximum negative correlation at +6 month lag over the central Pacific with the quasi-biennial oscillation. But the correlation coefficient reverses completely to that in Korea. In order to investigate the most prevailing interannual variability of rainfall related to the favored SSTA region, the lagged cross correlations between East Asia rainfall and SSTs over the NINO regions(NINO 1+2(0-10S, 90W-80W), NINO 3(5N-5S, 150W-90W), NINO 4(5N-5S, 160E-150W) and the western Pacific warm pool (5N-5S, 120E-160E) were analyzed. Among the lagged cross-correlation cycles in NINO regions, the maximum correlations for the negative lagged months prevail in NINO 1+2 and NINO 3, and the cross correlations for the positive lagged months NINO 4. It is noteworthy that correlation between the western Pacific warm pool SSTA and the monsoon rainfall in Korea and South China have the maximum value at negative 4 month lag. The evolution of the correlation between the East Asia monsoon rainfall and SSTA is linked to the equatorial convective cluster and related to northward propagating situation, and raising the possibility that the East Asia monsoon precipitation may be more fundamentally related to the interaction of intraseasonal oscillations and the sub-regional characteristics including the surface boundary conditions and the behavior of climatological air mass.