• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.2
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• pp.109-127
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• 2011

Atmospheric aerosols, small particles in the atmosphere, are one of the important parameters in climate change and human health. Additionally, accurate estimates of aerosol species are increasingly important in environmental impact assessment studies. Recent advances in global satellite remote sensing provide powerful tool for air quality monitoring. This study explores the potential usage of satellite derived data such as atmospheric aerosols for air quality monitoring as well as climate change study. The objectives of this study is to understand the general features of the global distribution of type dependent aerosols. A detailed spatio-temporal variability of the each different satellite dataset shows the variation of the global zonal average and specific geographical regions where the strong emission sources are located. Especially, significantly large aerosol amounts are observed in Asia and Africa because of the desert dust storm, anthropogenic and biomass burning emissions.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.127-128
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• 2002

대기 중 에어러솔이 지구의 복사수지에 미치는 영향을 파악하기 위한 연구들은 여러 각도에서 수행되고 있다. 2001년 봄철에 진행된 ACE-Asia 뿐만 아니라, ACE, ACE2, TARFOX, INDOEX 등등의 여러 집중 측정연구들이 수행되었다. 그러나 에어러솔 관측자료의 시공간적 한계는 여전히 남아있으며, 위성관측을 통한 에어러솔의 분석도, 다양한 지표면 상태 및 에어러솔의 특성에 대한 불완전한 가정 등으로 인해 충분한 정보를 제공하지 못하고 있다. (중략)

• Korean Journal of Remote Sensing
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• v.24 no.6
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• pp.559-569
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• 2008

The Geostationary Ocean Color Imager (GOCI) on board the Communication Ocean Meteorological Satellite (COMS), the first geostationary ocean color sensor, requires accurate atmospheric correction since its eight bands are also affected by atmospheric constituents such as gases, molecules and atmospheric aerosols. Unlike gases and molecules in the atmosphere, aerosols can interact with sunlight by complex scattering and absorption properties. For the purpose of qualified ocean remote sensing, understanding of aerosol-radiation interactions is needed. In this study, we show micro-physical and optical properties of aerosols using the Optical Property of Aerosol and Cloud (OPAC) aerosol models. Aerosol optical properties, then, were used to analysis the relationship between theoretical satellite measured radiation from radiative transfer calculations and aerosol optical thickness (AOT) under various environments (aerosol type and loadings). It is found that the choice of aerosol type makes little different in AOT retrieval for AOT<0.2. Otherwise AOT differences between true and retrieved increase as AOT increases. Furthermore, the differences between the AOT and angstrom exponent from standard algorithms and this study, and the comparison with ground based sunphotometer observations are investigated. Over the northeast Asian region, these comparisons suggest that spatially averaged mean AOT retrieved from this study is much better than from standard ocean color algorithm. Finally, these results will be useful for aerosol retrieval or atmospheric correction of COMS/GOCI data processing.

• Korean Journal of Remote Sensing
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• v.21 no.4
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• pp.273-285
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• 2005

This study has investigated the suitable wavelength for detecting biomass burning aerosols. We have performed the analysis of the wavelength at 380nm in near-UV, 400nm, 412nm, 460nm, and 490nm in visible, and 2100nm in shortwave infrared regions from the Global Imager measurements. It is well known that the UV bands have the advantage of the aerosols retrieval due to the low surface reflectance and a weak effect of Bidirectional Reflectivity Distribution Function. However, the pure surface reflectances of shortwave visible bands, except 412nm, are as low as that of 380nm in near-UV over northeast Asia. In order to detect the aerosol signal, we have retrieved the aerosol reflectance as a function of wavelength based on the surface reflectivity contrast method for the period of May 2003. It is interesting that the retrieved aerosol reflectance with 460nm is slightly more sensitive than that with 380nm. Additionally, we have applied the TOMS aerosol index method to determine the best pair for biomass burning aerosols and found that the pair of 380 and 460nm results in the best signal for retrieving aerosols.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.315-316
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• 1999

황해지역에서의 대기중 에어러솔 분포의 특징을 살피기 위하여 1999년 4월 말, 5월 초 인천에서 약 50km 떨어져 있는 경기도 옹진군 덕적도에서 Micro Pulse Lidar 측정과 에어러솔 샘플링을 수행하였다. 황해지역에서 봄철의 평균적인 에어러솔 농도 및 성분에 대한 연구와 함께 황사가 발생하였을 때의 특성에 대하여 연구하였고, 이 지역으로 유입되는 공기의 기원을 추적하기 위하여 등온위면 역궤적 분석을 수행 하였다.(중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.439-440
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• 2001

대기 중의 에어러솔 입자들은 직접적으로는 빛의 산란, 흡수 등 복사 평형에 영향을 미치며, 간접적으로는 구름 응결핵(CCN)으로 작용함으로써 알베도와 구름의 수명에 영향을 미치게 된다. 자연적인 에어러솔은 인위적 활동에 따른 황 화합물, 질소 화합물, 유기물. 매연 그리고 토양 먼지의 증가에 의해 사실상 교란되어 왔다. 인위적인 에어러솔에 의한 복사 강제력(radiative forcing)은 현재 전 지구적 평균이 -0.3~-3.5Wm$^{-2}$ 정도로 추정되며, 이것은 온실 기체에 의한 강제력인 +2.0~+2.8Wm$^{-2}$ 와 비교될 만 하다(IPCC, 1995). (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.442-443
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• 2002

인공위성에 의한 대기 에어러솔의 관측방법은 에어러솔이 기후에 미치는 영향의 평가에 있어서 중요한 요소가 되었다. 기본적으로 인공위성 원격탐사자료는 가시광선 영역역대의 밴드에서 대기중의 분자들이나 에어러솔에 의한 산란효과에 의해 영향을 받는다. 황사 현상과 같은 먼지구름은 인공위성 영상에서 쉽게 보이며 이러한 먼지 구름이 복사 강제 효과에 대한 기여도가 클 것으로 예측된다. (중략)

• Korean Journal of Remote Sensing
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• v.24 no.4
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• pp.369-379
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• 2008

The aerosol retrieval algorithm for the Moderate Resolution Imaging Spectroradiometer (MODIS) measurements was updated recently. This paper reports on the comparison and validation of two latest versions (Collection 4 and 5, shortly C004 and C005) of the MODIS aerosol product over northeast Asian region. The differences between the aerosol optical thickness (AOT) from the C004 and C005 retrieval algorithms and the correlation with ground based AERONET sunphotometer observations are investigated. Over the study region, spatially averaged annual mean AOT retrieved from C005 algorithm $(AOT_{C005})$ is about 0.035 AOT (5%) less than the C004 counterparts. The linear correlations between MODIS and AERONET AOT also are R=0.89 (slope=0.86) for the C004 and R=0.95 (slope=1.00) for the C005. Moreover, the magnitude of the mean error in $AOT_{C005}$, difference between MODIS AOT and AERONET AOT, is 40% less than that in $AOT_{C004}$.

• Journal of the Korean Association of Geographic Information Studies
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• v.16 no.2
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• pp.141-151
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• 2013

This study presents a modeling of aerosol extinction vertical profiles in Korea by using the Moderate Resolution Imaging Spectro-radiometer(MODIS) derived aerosol optical thickness(AOT) and ground based visibility observation data. The method uses a series of physical equations for the derivation of aerosol scale height and vertical profiles from MODIS AOT and surface visibility data. The modelled results under the standard atmospheric condition showed small differences with the standard aerosol vertical profile used in the radiative transfer model. Model derived aerosol scale heights for two cases of clean(${\tau}_{MODIS}=0.12{\pm}0.07$, visibility=$21.13{\pm}3.31km$) and hazy atmosphere(${\tau}_{MODIS}=1.71{\pm}0.85$, visibility=$13.33{\pm}5.66km$) are $0.63{\pm}0.33km$ and $1.71{\pm}0.84km$. Based on these results, aerosol extinction profiles can be estimated and the results are transformed into the KML code for visualization of dataset. This has implications for atmospheric environmental monitoring and environmental policies for the future.

• Journal of the Korean Society of Hazard Mitigation
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• v.6 no.3 s.22
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• pp.47-56
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• 2006

With the aim to develop the monitoring technology on background atmosphere and climate change over Korean Peninsula, observations and studies on chemical, physical and optical properties of the atmospheric aerosols are made. Aerosol number concentration are measured with Optical Particle Counter from 2001 to 2003 at Gosan for 8 size intervals from 0.3 to $25{\mu}m$ diameter range. For the seasonal variation, the number concentration of coarse particles in spring at Gosan was higher than other seasons due to the influence of sand storm in spring. There is no significant correlations between fine particles ($0.3{\sim}0.5{\mu}m$) and meteorological parameters, such as relative humidity, wind speed and visual range, while the correlation between the number concentration of small particles ($0.5{\sim}2.23{\mu}m$) and relative humidity showed a positive value. This trend was inversed for the case of wind speed: aerosol number concentration showed a small decreasing tendency with increasing wind speed for small particles but the high wind speed in winter season increased coarse particle concentration. Finally, Particles most efficient in light extinction were found to be at the size of about $0.5{\sim}1{\mu}m$.