• 한국환경과학회지
• /
• 제18권11호
• /
• pp.1271-1281
• /
• 2009

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.

• 대기
• /
• 제28권3호
• /
• pp.325-336
• /
• 2018

This study investigates robust features of interdecadal changes in the Northern hemisphere summer tropical-extratropical teleconnection occurred around the mid-to-late 1990s by analyzing four different reanalysis data for atmospheric circulation and temperature, two precipitation reconstructions, and two sea surface temperature (SST) data during the satellite observation era of 1980~2017. For the last 38 years, there has been a significant increasing trend in anticyclonic circulation at lower and upper troposphere and 2 m air temperature with wavenumber-5 Rossby wave structure in the Northern Hemisphere (NH) extratropics. The increase has been accompanied with the significant weakening and northward shift of jet stream over Eurasia and the North Pacific. It is further found that there has been a significant interdecadal shift occurred around the mid-to-late 1990s in the two distinct modes of tropical-extratropical teleconnection: Western Pacific-North America (WPNA) and circumglobal teleconnection (CGT) pattern. After mid-to-late 1990s, the WPNA has played more important role in modulating the extratropical atmospheric circulation and surface climate, which has been preferentially occurred during the El $Ni{\tilde{n}}o$-Southern Oscillation (ENSO) decaying or transition summer such as 1998, 2010 and 2016. During these summers, severe heat waves were occurred over many parts of the NH extratropics due to the combined effect of the increasing trend in the barotropic anticyclonic circulation and the significant WPNA across the NH. Although weakened, the CGT also contributed to some of hot summers over many parts of the NH extratropics such as 1999, 2000, 2008, 2011, and 2012 when weak to moderate La $Ni{\tilde{n}}o$ was persisted.

• 한국해양학회지:바다
• /
• 제18권4호
• /
• pp.266-276
• /
• 2013

바다-육지-대기로 이루어진 기후 시스템에서 가장 큰 탄소의 저장고는 바다이다. 바다가 대기로부터 탄소를 흡수하는 주요 수단은 생물 활동에 의한 것으로서, 광합성에 의해 유기 물질로 동화된 탄소가 해저로 침강하고 분해되는 과정에서 깊은 바다물은 탄소를 축적하게 된다. 이러한 탄소 수송 작용을 생물 펌프라 부르며, 해수면 탄소 농도를 낮춤으로써 대기 중 이산화탄소 분압을 낮은 상태로 유지해주는 중요한 기작이다. 생물 펌프에 의해 해저에 축적된 탄소는 해양 순환에 의해 해수면에 돌아오고, 해양-대기 기체 교환에 의해 대기로 배출된다. 바다가 대기와 소통하는 이산화탄소의 양은 과거 빙하기-간빙기 기후 변동과 관련하여 과거 수십만년동안 대기 중 이산화탄소 분압변화에 주도적인 역할을 하여 온 것으로 알려져 있다. 본 논문에서는 바다에서 일어나는 탄소 순환을 간단하게 소개하고, 해양 순환의 변화가 어떻게 탄소 순환을 변형시키고, 대기 중 이산화탄소에 영향을 미치는지를 기후 변동의 관점에서 살펴보고자 한다.

• Ocean and Polar Research
• /
• 제35권3호
• /
• pp.259-272
• /
• 2013

One of the factors influencing the climate around Korea is the oceanic-atmospheric variability in the tropical region between the eastern Indian and the western Pacific Oceans. Lack of knowledge about the air-sea interaction in the tropical Indo-Pacific region continues to make it problematic forecasting the ocean climate in the East Asia. The 'Tropical Indo-Pacific water transport and ecosystem monitoring EXperiment (TIPEX)' is a program for monitoring the ocean circulation variability between Pacific and Indian Oceans and for improving the accuracy of future climate forecasting. The main goal of the TIPEX program is to quantify the climate and ocean circulation change between the Indian and the Pacific Oceans. The contents of the program are 1) to observe the mixing process of different water masses and water transport in the eastern Indian and the western Pacific, 2) to understand the large-scale oceanic-climatic variation including El Nino-Southern Oscillation (ENSO)/Warm Pool/Pacific Decadal Oscillation (PDO)/Indian Ocean Dipole (IOD), and 3) to monitor the biogeochemical processes, material flux, and biological changes due to the climate change. In order to effectively carry out the monitoring program, close international cooperation and the proper co-work sharing of tasks between China, Japan, Indonesia, and India as well as USA is required.

• 융합신호처리학회논문지
• /
• 제11권4호
• /
• pp.298-302
• /
• 2010

체외 순환 보조 장치는 호흡부전 및 심부전 등에 사용하는 장치이며 세계적으로 많은 연구 개발과 임상에의 사용이 계속되고 있다. 이 장치들을 사용할 때 주의해야할 사항중 하나는 공기 색전증이다. 공기 색전증은 정맥혈내로 공기가 들어갈 수 있는 여러 가지 수술 과정 및 진단 과정의 합병증으로 일어날 수 있으며, 수술부위가 심장보다 위치, 수술 과정 중 체강, 체외 순환 보조 장치를 사용할 때 공기의 유입이 생길 수 있다. 이러한 문제를 해결하기위해 비유전율 상수의 변화를 이용한 공기방울 감지 장치를 개발했다. 모의순환 장치에서 실험해본 결과 튜브 안의 공기 양에 따라 신호의 차를 분명하게 보여주어 공기방울을 감지할 수 있었다.

• 한국환경과학회지
• /
• 제5권3호
• /
• pp.277-284
• /
• 1996

The Characteristics of atmospheric flow and dispersion of air pollutants in the mountainous coastal area were studied using two-dimensional model by the combination of land-sea breezes and transport. The pollutants emitted into the simulated wind field in considering with the mesoscale local circulations. The typical effects of land-sea breezes and tophography of coastal area on the dispersion are discussed in detail, and the model is proved as an useful tool to pridict real time pollutant transport by the results of application studies in Pusan, Korea where the urbanized coastal area with mountainous topography. It was found that sulfur dioxide ($SO_2$) are differently transported and concentrated as going inland by the influence of the sea breeze with topographic changes. Key words : land-sea breezes, sulfur dioxide, dispersion, coastal area.

• 한국환경과학회지
• /
• 제6권5호
• /
• pp.437-449
• /
• 1997

To predict diffusion and movement of k pollutants In coastal urban region a numerical simulation shouts be consider atmospheric flow field with land-sea breeze, mountain-valley wand and urban effects. In this study we used Lagrangian [article dispersion method In the atmospheric flow field of Pusan coastal region to depict diffusion and movement of the Pollutants emoted from particular sources and employed two grid system, one for large scale calculating region with the coarse mesh grid (CMG) and the other for the small region with the One mesh 914 (FMG). It was found that the dispersion pattern of the pollutants followed local circulation system in coastal urban area and wale air pollutants exhausted from Sasang moved Into Baekyang and Jang moutain, air pollutants from Janglim moved into Hwameong-dong region.

• 한국대기환경학회:학술대회논문집
• /
• 한국대기환경학회 2003년도 추계학술대회 논문집
• /
• pp.51-52
• /
• 2003

A numerical study on PM using a dispersion and deposition model which can analyze for both quantify and quality would not only offer us to understand our environment more easily, but also make it easy that we can make a plan in order to prevent air pollution. The U.S. EPA has proposed the CALPUFF modeling system as a guideline model for regulatory applications involving long-range transport and on a case-by-case basis for near-field applications where. non- steady- state effects which consider situations such as spatial variability in the meteorological fields, calm winds, fumigations, re-circulation or stagnation, and terrain or coastal effects may be important. (omitted)

• 한국환경과학회지
• /
• 제16권1호
• /
• pp.103-119
• /
• 2007

We have analysed the observed surface and vertical meteorological data to get atmospheric information over the Busan metropolitan area. For this, we have selected 10 days in all season such as spring, summer I(Jangma season), summer II(hot season), autumn and winter. The result which have performed cluster analysis using atmospheric data represented that these days are included to most frequently appeared synoptic cluster. We have simulated wind field around Busan metropolitan area which is assigned as $1km^2$ using RAMS. The calculated air temperature and the wind speed was similar to the observed the that, and the trends of daily variation showed good agreement. RMSE and IOA also showed reliable value. These results indicated the RAMS is able to simulate and predict detailed atmospheric phenomenon.

• International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
• /
• 제23권1호
• /
• pp.18-33
• /
• 1995

동쪽 연안지역에서 큰 경사를 갖인 산맥위를 흘러가는 종관규모의 서풍하에서 내부 중력파와 같은 강한 하강폭풍이 산의 후면에서 발생되어 진다. 주간에 해양에서 내륙으로 향하는 중규모의 열적 강화에 의해 유도되는 해풍순환이 동쪽으로 향하는 내부중력파에 기인하여 연안의 앞바다까지만 국한된다. 따라서 연안해 근처의 표층풍은 외해나 내륙의 위치에서보다 상대적으로 더 약하다. 명백하게 서풍의 내부중력파순환파 해면 근처에서 동풍 및 상층에서 서풍을 갖는 해풍순환과 같은 두개의 상이한 종류의 대기순환이 뚜렷하게 나타났다. 이런 상황에서 강릉시에서의 대기오염물질은 반대 방향의 두개의 상이한 순환에 의해 갇히게 되고 부유분진과 오존의 고농도가 초래되었다. 야간에 육지에서 연안해로 향하는 중규모의 육풍은 기존의 동쪽으로 향하는 하강풍과 협력하여 연안지역에서 서풍의 더욱 강화를 유도할 수 있었다. 산쪽에서 연안해로 향하여 부는 강한 표층풍에 의해 조절되는 부유분진의 농도는 추간의 경우보다 야간에 비교적 더 높았으며, 상층대기로 부터 지표면으로 오존의 하양수송에 기인하여 오존의 농도가 주간보다 야간에 매우 높았다. 결과로 바람폭풍하의 산악연안지역에서 대기오염농도는 바람푹풍 전.후보다 더 높았다.