An attempt is made to analyse characteristic features of heavy rainfalls which occur at the metropolitan area of the Korean peninsular the on- and off- Changma season. For this, two representative heavy rainfall episodes are selected; one is the on-Changma season wherein a torrential rain episode happened at Goyang city on 12 July 2006, and the other is the off-Changma season, a heavy rainfall event in Seoul on 21 September 2006. Both recorded considerable amounts of precipitation, over 250mm in a half-day, which greatly exceeded the amount expected by numerical prediction models at those times, and caused great damage to property and life in the affected area. Similarities in the characteristics of both episodes were shown by; the location of upper-level jet streak and divergence fields of the upper wind over heavy rainfall areas, significantly high equivalent potential temperatures in the low atmospheric layer due to the entrainment of hot and humid air by the low-level jet, and the existence of very dry air and cold air pool in the middle layer of the atmosphere at the peak time of the rainfall events. Among them, differences in dynamic features of the low-level jet and the position of rainfall area along the low-level jet are remarkable.

기상청 내외의 기상·기후 및 기후변화의 R&D와 관련된 사회경제적 변화와 새로운 요구들에 대하여 개개 기관들의 근원적 임무들에 대한 역할들이 조사되었다. 선진국 기관들과 국제기구들의 서비스 내에서 R&D 프로젝트들의 현황과 미래 경향들이 역시 조사되었다. 그러한 전망과 변화들에 근거하여 기상청 비전과 정책과 연관된 R&D 관리와 운영의 미래 개발에 대한 방향들이 유도되었다. 첫째, 소프트웨어나 시스템의 개발, 개선 및 창출하기 위한 현업용 R&D 자금을 가진 내부 기상청 기금과, 국립기상연구소에서 얘기하는 기상청 현업과 정부기관의 대형 프로젝트를 위한 시스템이나 소프트웨어의 지원을 위한 기금, 그리고 나머지는 기상과 기후/기후변화에 대해 기본과학기술을 연구하는 기상지진연구사업단(CATER), 기후과학연구관리단(RACS) 등과 같은 순수 R&D 기금에 대한 기상청 내부의 수행구조를 분석하는 것이다. 둘째, 연구결과와 달성에 대해 최대화하기 위한 R&D 프로젝트 추적 시스템적인 개선의 연구 개선들과 전략을 분해하는 것으로, 평가지수의 다른 가중가치와 방법을 추가하는 것과 같은 시스템적인 개정에 대한 두가지 방법이 있다. 나머지는 여러 분야들에서 도래된 미래 계획에 대한 핵심기술 전략을 개발하는 것이다. R&D에 대한 기상청 투자 전략들을 이끌어갈 새로운 매트릭스들에 대한 이해의 중요성은 첨단기술에 대해 한국의 국가 및 국제 경쟁력을 더욱 효과적으로 강화하기 위해 고려되어야 한다.

The heavy snowfall event over the eastern part of Seoul, Korea on Mar. 04, 2008 has been abruptly occurred after the frontal system with the heavy snowfall event had been past over the Korean peninsula on Mar. 03, 2008. Therefore, this heavy snowfall event couldn't be predicted well by any means of theoretical knowledges and models. After the cold front passed by, the cold air mass was flown over the peninsula immediately and became clear expectedly except the eastern part and southwestern part of peninsula with some large amount of snowfall. Even though the wide and intense massive cold anticyclone was expanded and enhanced by the lowest tropospheric baroclinicity over the Yellow Sea, but the intrusion and eastward movement of cold air to Seoul was too slow than normally predicted. Using the data of numerical model, satellite and radar images, three dimensional analysis products(KLAPS : Korea Local Analysis and Prediction System) of the environmental conditions of this event such as temperature, equivalent potential temperature, wind, vertical circulation, divergence, moisture flux divergence and relative vorticity could be analyzed precisely. Through the analysis of this event, the formation and westward advection of lower cyclonic circulation with continuously horizontal movement of air into the eastern part of Seoul by the analyses of KLAPS fields have been affected by occurring the heavy snowfall event. As the predictability of abrupt snowfall event was very hard and dependent on not only the synoptic atmospheric circulation but also for mesoscale atmospheric circulation, the forecaster can be predicted well this event which may be occurred and developed within the very short time period using sequential satellite images and KLAPS products.

The formation mechanism of the snow cells of the Yellow Sea associated with snowfall over the southwestern part of Korea on 4 February, 2004 has been investigated using special upper-air sounding and radar data obtained for the KEOP (Korea Enhanced Observing Period) Intensive Observing Period (IOP). Results show that the types of snow cells for the selected period are classified into L(Longitudinal)-mode, Low-level convergence, and T(Transverse)-mode with their evolution from L-mode to T-mode. In particular, the existence of low-level warm and humid layer associated with temporally southwesterly inflow for about 4 hours provides a favorable condition in forming the T-mode snow cells. The vertical depth of the T-mode snow cells is deeper than that of L-mode ones due to the southeastward penetration of cold and dry air into relatively warm and humid air. In addition, it is found that wind shear vector between 1000 hPa and 600 hPa is one of the factors which control the orientation of snow cells in formation embedded into the snowbands for the both modes.