• 한국대기환경학회지
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• 제25권1호
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• pp.57-74
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• 2009

In order to clarify the vertical ozone distribution in planetary boundary layer of coastal area with complex terrain, an observation campaign was carried out around Gwangyang Bay with dense pollutant emission sources during two days from June, 4 2007. For this observation are Radiosonde, SODAR(SOnic Detection And Ranging) and Tethered ozone sonde were employed. The surface meteorological and photochemical observation data provided by AWS (Automatic Weather System) and AQMS (Air Quality Monitoring System) were also applied for analysis. Synoptic condition is strongly associated with lower level ozone distribution in complex terrain coastal area. Since mesoscale circulation induced by difference of characteristics of land and sea and orographic forcing is predominant under calm synoptic condition, vertical distribution of ozone is complicate and vertical ozone concentration greatly fluctuated. However in second day when synoptic influence become strong, ozone concentration in lower levels is vertically uniform regardless of observation level. This results in vertical observation indicates that vertical ozone distribution is often determined by synoptic condition and also affects surface ozone concentration.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.989-992
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• 2006

The new approach to the problem of oil spill detection consisting in combined use of all available quasiconcurrent satellite information (AVHRR NOAA, TOPEX/Poseidon, Jason-1, MODIS Terra/Aqua, QuikSCAT) is suggested. We present the results of the application of the proposed approach to the operational monitoring of seawater condition and pollution in the coastal zone of northeastern Black Sea conducted in 2006. This monitoring is based on daily receiving, processing and analysis of data different in nature (microwave radar images, optical and infrared data), resolution and surface coverage. These data allow us to retrieve information on seawater pollution, sea surface and air-sea boundary layer conditions, seawater temperature and suspended matter distributions, chlorophyll a concentration, mesoscale water dynamics, near-surface wind and surface wave fields. The focus is on coastal seawater circulation mechanisms and their impact on the evolution of pollutants.

• 대기
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• 제16권3호
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• pp.187-201
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• 2006

During summer (JJA) of 2004, a record-high temperature in Korea appeared at Miryang ($38.5^{\circ}C$ on July 30). Moreover, Miryang showed the most frequent occurrence (25 days in JJA) of the daily highest temperature among observational sites in Korea. Based on meteorological analysis, it is found that this phenomenon is caused by neither the global warming effect nor the urban climate effect. It is caused by the mesoscale and synoptic and/or global scale atmospheric circulations, as evidenced by several factors described below. Firstly, the hottest areas have normally occurred not at a point but over an area, particularly along an axis connecting Sancheong and Daegu. But in 2004, this axis has moved southward and locates over Namhae-Miryang due to northerlies that were induced by the heating effect related to the low snow-cover on the Tibet Plateau. Secondly, although the maximum temperature was the highest among observational sites in Korea, the daily mean temperature and the number of nights with air temperature over $25^{\circ}C$ were not the highest at Miryang. Thirdly, the downdraft induced by the second circulation of typhoon and abnormal development of the North-Pacific High were found to have exerted an important role.

• 한국농공학회논문집
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• 제52권3호
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• pp.57-64
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• 2010

The impacts of climate change on yield and evapotranspiration of rice have been modeled using AquaCrop model developed by Food and Agriculture Organization (FAO). Climate change scenario downscaled by Mesoscale Model 5 (MM5) regional model from ECHO-G General Circulation Model (GCM) outputs by Korea Meteorological Research Institute (METRI) was used in this study. Monthly average climate data for baseline (1971-2000) and three time periods (2020s, 2050s and 2080s) were used as inputs to the AquaCrop model. The results showed that the evapotranspiration after transplanting was projected to increase by 4 % (2020s), 8 % (2050s) and 14 % (2080s), respectively, from the baseline value of 464 mm. The potential rice yield was 6.4 t/ha and water productivity was 1.4 kg/$m^3$ for the baseline. The potential rice yield was projected to increase by 23 % (2020s), 55 % (2050s), and 98 % (2080s), respectively, by the increased photosynthesis along with the $CO_2$ concentration increases. The water productivity was projected to increase by 19 % (2020s), 44 % (2050s), and 75 % (2080s), respectively.

• 대한원격탐사학회지
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• 제16권4호
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• pp.293-303
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• 2000

The typhoon Jelawat, which was formed over the tropical Pacific ocean on August 1, 2000 and made a landfall over China on August 10, 2000, was observed by Korea Multi-purpose Satellite (KOMPSAT-1) Ocean Scanning Multispectral Imager (OSMI), Tropical Rainfall Measuring Mission (TRMM)/Precipitation Radar(PR) and Quick Scatterometer (QuikSCAT). In spite of discontinuous observation, important mesoscale features of typhoon depending on life cycle were detected prominently. It is possible to distinguish on the OSMI photograph between the eye-wall convection and the stratiform and other convective clouds near the center of typhoon Jelawat. The TRMM/PR observations show quite clearly the eye-wall convection, stratiform regions, and convective bands. Vertical cross section of rainfall in the genesis stage of typhoon Jelawat exhibits circular ring of intense convection surrounding the eye. The mature stage of typhoon Jelawat consists of a strong rotational circulation with clouds which are well organized about a center of low pressure. The OSMI, TRMM/PR and QuikSCAT measurements presented here agree qualitatively with each other and provide a wealth of information on the structure of typhoon Jelawat.

• Asia-Pacific Journal of Atmospheric Sciences
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• 제54권4호
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• pp.575-585
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• 2018

In the case study of this paper, sensitivity experiments are carried out using the mesoscale non-hydrostatic Weather Research and Forecasting (WRF) model to investigate the impact of tropical cyclone (TC) Soudelor (2003) on the East Asian subtropical upper-level jet (EASJ) before TC Soudelor transformed into an extratropical cyclone. The physical mechanism for changes in the EASJ intensity and position caused by TC Soudelor is explored. Results indicate that TC Soudelor would warm the air in the middle and upper troposphere over the Japan Sea and the adjacent areas through stimulating northward propagating teleconnection pattern as well as releasing large amounts of latent heat, which led to increase (decrease) the meridional air temperature gradient to the south (north) below the EASJ axis. As a result, the geopotential height abnormally increased in the upper troposphere, resulting in an anomalous anticyclonic circulation belt along the EASJ axis. Correspondingly, the westerly winds to the north (south) of the EASJ axis intensified (weakened) and the EASJ axis shifted northward by one degree. The case study also suggests that before the extratropical cyclone transition of TC Soudelor, the TC activities had exerted significant impacts on the EASJ through thermodynamic processes.

• 한국환경과학회지
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• 제5권2호
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• pp.153-170
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• 1996

멕시코 만에서 1987~1988년에 부유 및 칩강입자에 존재하는 광합성 색소 및 그 분해산물은 HPLC를 이용하여 측정하였다. 클로로필과 카로틴계열 및 그 분해산물의 단기 침하율이 Cold-Core Ring 과 Warm-Core Ring에서 비교 분석되었다. 클로로필 a는 CCR과 WCR에서 공통적으로 우세한 포르피린이었으며 카로틴계열 색소 중에는 19'-hwxanoyloxyfucoxanthin이 우세하였다. 초식자의 섭이과정에서 생성되는 것으로 알려진 phaeophobide a가 조사지역 침강입자에 우세하게 나타나는 분해색소 이었따. CCR에서의 전체색소 침하율은 WCR보다 한단게 높게 나타났다. WCR에서 색소현존량은 하루에 1% 이하가 유광밖으로 침하 되었는데 이 사실은 멕시코 만에서 부유고형입자의 재순환은 빠르게 일어나고 있지 않음을 의미한다.

• 한국물환경학회지
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• 제25권6호
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• pp.821-831
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• 2009

The study was aimed to assess the expected impact of climate change on the water cycle and soil losses in Daecheong Reservoir watershed, Korea using the Soil and Water Assessment Tool (SWAT) that was validated for the watershed in a previous study. Future climate data including precipitation, temperature and humidity generated by introducing a regional climate model (Mesoscale Model Version 5, MM5) to dynamically downscale global circulation model (European Centre Hamburg Model Version 4, ECHAM4) were used to simulate the hydrological responses and soil erosion processes in the future 100 years (2001~2100) under the Special Report on Emissions Scenario (SRES) A1B. The results indicated that the climate change may increase in the amount of surface runoff and thereby sediment load to the reservoir. Spatially, the impact was relatively more significant in the subbasin Bocheongcheon because of its lower occupation rate of forest land compared to other subbasins. Seasonally, the increase of surface runoff and soil losses was more significant during late summer and fall season when both flood control and turbidity flow control are necessary for the reservoir and downstream. The occurrence of extreme turbidity flow events during these period is more vulnerable to reservoir operation because the suspended solids that remained water column can be resuspended by vertical mixing during winter turnover period. The study results provide useful information for the development of adaptive management strategy for the reservoir to cope with the expected impact of future climate change.

• 물과 미래
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• 제27권3호
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• pp.45-54
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• 1994

물수지 모델을 사용하여 발생시킨 시계열에 대해서 프랙탈(Fractal) 차원의 기본 이론이 소개 및 적용되었고 물수지 방정식이 넓은 지역에 대해 계절 시간 규모로 분석하였다. 중간 규모 순환의 발생과 변화에 있어 강우의 국부 재순환과 토양 수분의 동력학적 영향이 명시적으로 포함되어 있고 지체 시간 또한 분석에서 고려되었다. 시스템은 전개에 있어 변수 값들에 따라 고정점, 한계주기 그리고 카오스(Chaos)적인 행태와 같은 서로 다른 결과를 보여 주었다. 발생된 시계열의 추계학적인 행태는 궤적들이 초기 조거넹 매우 민감한 한정된 수의 방정식을 가지는 비선형 동력학 시스템으로부터 발생하는 확정론적 카오스 때문이다. 강우의 특성으로부터 발생하는 잡음은 어트랙터(Attractor)의 조직화된 구조를 파괴시키는데, 잡음의 존재에도 불구하고 어트랙터가 존재한다는 것은 시스템의 전개의 다기 예측에 있어 매우 중요하다고 할 수가 있다. 이러한 비선형 동력계가 가지고 있는 의미는 수문자료나 현상들의 해석과 모델링에 있어 중요하다.

• 대한원격탐사학회지
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• 제20권2호
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• pp.103-116
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• 2004

지표 온도를 산출하는 중규모 대기 모형은 일반적으로 태양 복사의 직달 일사량에 대하여 경사진 지형의 효과를 고려하지 않는다. 이는 실제 태양 복사량의 국지적 차이를 나타내지 못하며, 그 결과 국지적인 지표 온도에서의 큰 오차를 가져온다. 따라서 지형의 기하학적 특성뿐만 아니라 지표의 식생 특성을 고려함으로써, 정확한 국지적 지표 온도를 나타내고자 하였다. 본 연구의 목적은 GIS의 그리드 모형을 적용한 에너지 균형 모형(EBM)을 사용하여 진단적으로 지역적 지표 온도를 산출하는 것이다. 본 연구에서, 한반도 남부 지역의 지형적 비균질성은 그리드 내의 지형 방위각과 경사각의 함수인 조도각의 항으로써 흡수된 지표 일사량 계산에 고려되었다. 또한 지표 온도 변화에 주요한 변수가 되는 지표의 식생 특성이 NDVI의 항으로 사용하였다. 지표의 경사진 지형의 효과와 식생 특성이 고려된 지표 온도의 상세한 지역적 분포가 연구 결과로써 제시되었다. 이러한 지역적 지표 온도 분포는 저층 대기에서 지형에 의한 지역 순환을 형성할 수 있으며, 실제 자연에서의 지역 순환을 더욱 잘 설명할 수 있을 것이다.