• Journal of Astronomy and Space Sciences
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• 제35권2호
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• pp.105-109
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• 2018

El $Ni{\tilde{n}}o$ is the largest fluctuation in the climate system, and it can lead to effects influencing humans all over the world. An El $Ni{\tilde{n}}o$ occurs when sea surface temperatures in the central and eastern tropical Pacific Ocean become substantially higher than average. We investigated the change in sea surface temperature in the Pacific Ocean during the El $Ni{\tilde{n}}o$ period of 2015 and 2016 using the advanced very-high-resolution radiometer (AVHRR) of NOAA Satellites. We calculated anomalies of the Pacific equatorial sea surface temperature for the normal period of 1981-2010 to identify the variation of the 2015 El $Ni{\tilde{n}}o$ and warm water area. Generally, the warm water in the western tropical Pacific Ocean shifts eastward along the equator toward the coast of South America during an El $Ni{\tilde{n}}o$ period. However, we identified an additional warm water region in the $Ni{\tilde{n}}o$ 1+2 and Peru coastal area. This indicates that there are other factors that increase the sea surface temperature. In the future, we will study the heat coming from the bottom of the sea to understand the origin of the heat transport of the Pacific Ocean.

• 환경영향평가
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• 제20권2호
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• pp.199-205
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• 2011

The Saemangeum embankment construction have changed the flowing on the topography of the coastal marine environment. However, the variety of ecological factors are changing from outside of Saemangeum embankment area. The ecosystem of various marine organisms have led to changes by sea surface temperature. The aim of this study is to monitoring of sea surface temperature(SST) changes were measured by using thermal infrared satellite imagery, MODIS and Landsat. The MODIS data have the high temporal resolution and Landsat satellite data with high spatial resolution was used for time series monitoring. The extracted informations from sea surface temperature changes were compared with the dyke to allow them inside and outside of Saemangeum embankment. The spatial extent of the spread of sea water were analyzed by SST using MODIS and Landsat thermal channel data. The difference of sea surface temperature between inland and offshore waters of Saemangeum embankment have changed by seasonal flow and residence time of sea water in dyke.

• 현장과학교육
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• 제12권1호
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• pp.113-126
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• 2018

R&E (Research and Education) 프로그램은 교육과정에서 접하기 어려운 다양한 과학 연구 경험의 기회를 학생들에게 제공하여 과학적 사고력과 문제 해결 능력, 창의력을 발달시킬 수 있는 계기를 마련해준다는 점에서 중요성이 강조되고 있다. 본 연구의 목적은 인공위성 자료를 활용하여 우리나라 연안 해역의 고해상도 해수면온도 자료를 산출하는 방법을 학생에게 적합하게 재구성하여 과학 영재 대상 R&E 프로그램으로 개발하는 것이다. 경기만 해역을 포함한 해역의 고해상도 해수면온도 자료를 산출하고 시공간적 분포를 이해하기 위하여 2013년 12월 21일부터 2017년 11월 30일까지 총 9장의 Landsat 8 OLI/TIRS (Operational Land Imager and Thermal InfraRed Sensor) 인공위성 자료를 수집하였다. 정확한 해수면온도 분포를 파악하기 위해 SRTM (Shuttle Radar Topography Mission) DEM (Digital Elevation Model) 자료를 활용하여 육지를 탐지하였고, 지표이용분류 알고리즘을 적용하여 조간대를 탐지하였으며, Landsat 8 OLI/TIRS 인공위성의 가시광선 영역 밴드(band)에 임계치(threshold)를 적용하여 구름을 탐지하였다. 전처리된 Landsat 8 OLI/TIRS 인공위성 자료에 다중 채널 회귀분석법(Multi-Channel Sea Surface Temperature, MCSST)을 적용하여 경기만 해역의 고해상도 해수면온도 자료를 산출하였다. 실제 교육 현장에서 활용 가능한 R&E 프로그램을 개발하기 위해 연구 과정을 단순화하고, 학생들이 단계적으로 연구 과정을 수행할 수 있도록 각 단계에 적합한 활동지를 개발하였다. 과학 영재 학생들을 대상으로 2017년 6월 24일부터 2018년 1월 13일까지 R&E 프로그램 수업을 진행하였고, 인공위성 자료 기반 R&E 프로그램의 실제 교육 현장 활용 가능성을 확인하였다.

• 대한원격탐사학회지
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• 제12권1호
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• pp.60-80
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• 1996

AVHRR(Advanced Very High Resolution Radiometer) on NOAA satellite provides data in five spectral, one in visible range, one in near infrared and three in thermal range. In this paper, application of NOAA/AVHRR data is studied for environment monitoring such as cloud top temperature, surface temperature, albedo, sea surface temperature, vegetation index, forest fire, flood, snow cover and so on. The analyses for cloud top temperature, surface temperature, albedo, sea surface temperature, vegetation index and forest fire showed reasonable agreement. But monitoring for flood and snow cover was uneasy due to the limitations such as cloud contamination, low spatial resolution. So this research had only simple purpose to identify well-defined waterbody for dynamic monitoring of flood. Based on development of these basic algorithms, we have a plan to further reseach for environment monitoring using AVHRR data.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.864-867
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• 2006

Thermal infrared images of Landsat-5 TM and Landsat-7 ETM+ sensors have been unrivalled sources of high resolution thermal remote sensing (60m for ETM+, 120m for TM) for more than two decades. Atmospheric effect that degrades the accuracy of Sea Surface Temperature (SST) measurement significantly, however, can not be corrected as the sensors have only one thermal channel. Recently, MODIS sensor onboard Terra satellite is equipped with dual-thermal channels (31 and 32) of which the difference of at-satellite brightness temperature can provide atmospheric correction with 1km resolution. In this study we corrected the atmospheric effect of Landsat SST by using MODIS data obtained almost simultaneously. As a case study, we produced the Landsat SST near the eastern and western coast of Korea. Then we have obtained Terra/MODIS image of the same area taken approximately 30 minutes later. Atmospheric correction term was calculated by the difference between the MODIS SST (Level 2) and the SST calculated from a single channel (31 of Level 1B). This term with 1km resolution was used for Landsat SST atmospheric correction. Comparison of in situ SST measurements and the corrected Landsat SSTs has shown a significant improvement in $R^2$ from 0.6229 to 0.7779. It is shown that the combination of the high resolution Landsat SST and the Terra/MODIS atmospheric correction can be a routine data production scheme for the thermal remote sensing of ocean.

• 한국지구과학회지
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• 제44권4호
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• pp.255-263
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• 2023

Western coastal area of Chungnam, including Cheonsu Bay and Garorim Bay, has suffered from hot and cold extremes. In this study, the extreme sea surface temperature on the western coast of Chungnam was analyzed using the quantile regression method, which extracts the linear regression values in all quantiles. The regional MOHID (MOdelo HIDrodinâmico) model, with a high resolution on a 1/60° grid, was constructed to reproduce the extreme sea surface temperature. For future prediction, the SSP5-8.5 scenario data of the CMIP6 model were used to simulate sea surface temperature variability. Results showed that the extreme sea surface temperature of Cheonsu Bay in August 2017 was successfully simulated, and this extreme sea surface temperature had a significant negative correlation with the Pacific decadal variability index. As a result of future climate prediction, it was found that an average of 2.9℃ increased during the simulation period of 86 years in the Chungnam west coast and there was a seasonal difference (3.2℃ in summer, 2.4℃ in winter). These seasonal differences indicate an increase in the annual temperature range, suggesting that extreme events may occur more frequently in the future.

• 한국지리정보학회지
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• 제9권4호
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• pp.224-232
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• 2006

본 연구는 Landsat Thematic Mapper (TM) 영상의 열적외선 (Thermal Infrared: TIR) 밴드 자료를 이용하여 시화호와 그 주변지역의 해수면 온도 (SST: sea surface temperature)를 검출하고, 시화방조제 공사 후의 토지피복변화를 파악하기 위해 수행되었다. 해수면 온도의 측정은 해양체계 뿐만 아니라 해양과 대기 사이의 열적인 경계범위 연구에 있어 중요하다. 1970년대 이후, AVHRR (advanced very high resolution radiometer)과 Landsat TM (Thematic Mapper)과 같은 인공위성 영상의 원격탐사기법을 이용한 해수면 온도의 추출이 이루어졌다. 그러나 AVHRR 영상은 우리나라의 서해안 지역과 같은 매우 복잡한 해안선을 가지고 있는 지역에서는 조악한 공간 해상도로 인해 해수표면온도 추출에 한계가 있다. Landsat TM 위성영상은 본 연구지역과 같이 복잡하고 좁은 해안지역의 해수면 온도 추출에 유용하게 사용된다고 판단된다.

• 한국측량학회지
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• 제26권3호
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• pp.219-225
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• 2008

원자력 발전소의 주변 지역은 해안지역이고 비교적 광범위하므로, 환경 변화를 감시하는데 많은 어려움이 있다. Landsat ETM+영상은 해상도가 30m 급이나 온도정보 추출에 있어 대기보정을 못하는 문제를 가지고 있다. MODIS 영상의 경우 2개의 적외선 밴드를 이용하여 대기보정된 비교적 적확한 온도를 추출할 수 있으나 해상도가 1km이다. 따라서, 두 위성영상의 자료를 이용한다면 대기보정된 고해상도의 온도자료를 추출할 수 있다. 본 연구에서는 대상지역의 Landsat ETM+영상에 대하여 기하보정을 수행하고, 방사휘도 및 온도를 산정한 후 MODIS영상을 이용하여 대기보정을 수행하였다. 그 결과 울진 원자력발전소 주변 연근해 지역과 온배수의 영향을 받지 않는 동쪽으로 5km 떨어진 동일 면적의 지역과 비교하여 보았을 때 약 $3.5^{\circ}C$ 높은 것을 알 수 있었다.

• 한국환경과학회지
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• 제19권2호
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• pp.171-184
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• 2010

Accurate simulation of the meteorological field is very important to assess the wind resources. Some researchers showed that sea surface temperature (SST) plays a leading role on the local meterological simulation. New Generation Sea Surface Temperature (NGSST), Operational Sea Surface Temperature and Sea Ice Analysis (OSTIA), and Real-Time Global Sea Surface Temperature (RTG SST) have different spatial distribution near the coast and OSTIA shows the best accuracy compared with buoy data in the southeastern coast of the Korean Peninsula. Those SST products are used to initialize the Weather Research and Forecasting (WRF) Model for November 13-23 2008. The simulation of OSTIA shows better result in comparison with NGSST and RTG SST. NGSST shows a large difference with OSTIA in horizontal and vertical wind fields during the weak synoptic condition, but wind power density shows a large difference during strong synoptic condition. RTG SST shows the similar patterns but smaller the magnitude and the extent.

• 한국대기환경학회지
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• 제25권5호
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• pp.432-449
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• 2009

In this study, the effects of high-resolution land cover on the simulation of near-surface meteorological fields were evaluated in two different coastal regions using Weather Research and Forecasting (WRF) model. These analyses were performed using the middle classification land cover data upgraded by the Korean Ministry of Environment (KME). For the purpose of this study, two coastal areas were selected as follows: (1) the southwestern coastal (SWC) region characterized by complex shoreline and (2) the eastern coastal (EC) region described a high mountain and a simple coastline. The result showed that the application of high-resolution land cover were found to be notably distinguished between the SWC and EC regions. The land cover improvement has contributed to generate the realistic complex coastline and the distribution of small islands in the SWC region and the expansion of urban and built-up land along the sea front in the EC region, respectively. The model study indicated that the improvement of land cover caused a temperature change on wide areas of inland and nearby sea for the SWC region, and narrow areas along the coastal line for the EC region. These temperature variations in the two regions resulted in a decrease and an increase in land-breeze and sea-breeze intensity, respectively (especially the SWC region). Interestingly, the improvement of land cover can contribute large enough to change wind distributions over the sea in coastal areas.