• Title/Summary/Keyword: NOAA

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Estimation of evapotranspiration using NOAA-AVHRR data (NOAA-AVHRR data를 이용한 증발산량추정)

  • Shin, Sha-Chul;Sawamoto, Masaki;Kim, Chi-Hong
    • Water for future
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    • v.28 no.1
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    • pp.71-80
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    • 1995
  • The purpose of this study is to estimate evapotranspiration and its spatial distribution using NOAA-AVHRR data. Evapotranspiration phenomena are exceedingly complex. But, factors which control evapotranspiration can be considered that these are reflected by conditions of the vegetation. To evaluate the vegetation condition as a fixed quantity, the NDVI(Normalized Difference Vegetation Index) calculated from NOAA data is utilized. In this study, land cover classification of the Korean peninsula using property of NDVI is performed. Also, from the relationship between evapotranspiration and NDVI histograms, evapotranspiration and its distribution of the Han River basin are estimated.

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A RAMS Atmospheric Field I Predicted by an Improved Initial Input Dataset - An Application of NOAA SST data - (초기 입력 자료의 개선에 의한 RAMS 기상장의 예측 I - NOAA SST자료의 적용 -)

  • Won, Gyeong-Mee;Jeong, Gi-Ho;Lee, Hwa-Woon;Jung, Woo-Sik;Lee, Kang-Yoel
    • Journal of Environmental Science International
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    • v.18 no.5
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    • pp.489-499
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    • 2009
  • In an effort to examine the Regional Atmospheric Modeling System (RAMS ver. 4.3) to the initial meteorological input data, detailed observational data of NOAA satellite SST (Sea Surface Temperature) was employed. The NOAA satellite SST which is currently provided daily as a seven-day mean value with resolution of 0.1 $^{\circ}$ grid spacing was used instead of the climatologically derived monthly mean SST using in RAMS. In addition, the RAMS SST data must be changed new one because it was constructed in 1993. For more realistic initial meteorological fields, the NOAA satellite SST was incorporated into the RAMS-preprocess package named ISentropic Analysis package (ISAN). When the NOAA SST data was imposed to the initial condition of prognostic RAMS model, the resultant performance of near surface atmospheric fields was discussed and compared with that of default option of SST. We got the good results that the new SST data was made in a standard RAMS format and showed the detailed variation of SST. As the modeling grid became smaller, the SST differences of the NOAA SST run and the RAMS SST43 (default) run in diurnal variation were very minor but this research can apply to further study for the realistic SST situation and the development in predicting regional atmospheric field which imply the regional circulation due to differential surface heating between sea and land or climatological phenomenon.

Meteorological Water Balance Analysis using NOAA/AVHRR Satellite Images (NOAA/AVHRR 위성영상을 이용한 기후학적 물수지 분석)

  • Kwon, Hyung Joong;Shin, Sha Chul;Kim, Seong Joon
    • Proceedings of the Korea Water Resources Association Conference
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    • 2004.05b
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    • pp.262-266
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    • 2004
  • 본 논문의 목적은 NOAA/AVHRR 위성영상으로부터 추출한 식생정보를 이용하여 실제증발산량을 산정하고, 이와 함께 강우 분포도 및 잠재증발산량을 이용하여 광역적인 물수지 분석을 수행하는 것이다. NOAA/AVHRR 위성영상으로부터 실제증발산량 산정을 위하여 식생정보와 Molten의 실제증발산량과의 회귀분석을 통한 선형 회귀식을 도출하였으며, Hamon 방법에 의하여 잠재증발산량을 산정하였다. 기후학적 물수지 분석을 통하여 광역적 과잉수분량 및 부족수분량 분포도를 작성하였으며, 이를 이용하여 가뭄파악을 위한 지표인 습윤지표 분포도를 작성하였다.

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The research evaluation of shadow influence in NOAA AVHRR data (NOAA AVHRR 자료에서 구름으로 인한 그림자 영향에 관한 조사)

  • Kim, Dong-Hee;Ryutaro, Tateishi;Choi, Seung-Pil;Choi, Chul-Soon
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2004.11a
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    • pp.281-284
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    • 2004
  • 광범위한 면적의 토지피복분류를 관찰하는데 유용하게 사용되고 있는 NOAA AVHRR 자료는 자료의 방대한 양과 구름에 의한 영향을 없애기 위하여 일반적으로 MVC(Maximum Value Composite) 처리를 하여 사용한다. 그러나 수신당시의 여러 가지 환경인자(구름, 저주파 노이즈, 산란, 구름의 그림자 등)에 의하여 각 채널의 패턴이 변화하여 오독을 할 위험성이 있다. 특히 그림자의 영향에 의해 측정치가 변화하는 NOAA 위성의 채널2영역에서는 이러한 특징이 두드러진다. 따라서 본 연구에서는 지상에서 실제로 측정한 자료를 기초로 하여 NOAA 영상자료에서 구름으로 인한 그림자의 영향에 관하여 조사하였고, 한 픽셀안에서 그림자의 영향이 60%이상이 될 경우에는 오독의 가능성이 높은 것으로 나타났다.

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Climatic Water Balance Analysis Using NOAA/AVHRR Satellite Images (NOAA/AVHRR 위성영상을 이용한 기후학적 물수지 분석)

  • Kwon, Hyung-Joong;Shin, Sha-Chul;Kim, Seong-Joon
    • Journal of The Korean Society of Agricultural Engineers
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    • v.47 no.1
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    • pp.3-9
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    • 2005
  • The purpose of this study was to analyze the climatic water balance of the Korean peninsula using meteorological data and the evapotranspiration (ET) derived from NOAA/AVHRR, Quantifying water balance components is important to understand the basic hydrology, In this study, a simple method to estimate actual ET was proposed based on a regression approach between NDVI and Morton's actual ET using NOAA/AVHRR data, The Mortons actual ET for land surface conditions was evaluated using a daily meteorological data from 77 weather stations, and the monthly averaged Morton's ETs for each land cover was compared with the monthly NDVIs during the year 2001. According to the climatic water balance analysis, water deficit and surplus distributed maps were created from spatial rainfall, soil moisture, and actual and potential ETs map, The results clearly showed that the temporal and spatial characteristics of dryness and wetness may be detected and mapped based on the wetness index.

Adjoint-Based Observation Impact of Advanced Microwave Sounding Unit-A (AMSU-A) on the Short-Range Forecast in East Asia (수반 모델에 기반한 관측영향 진단법을 이용하여 동아시아 지역의 단기예보에 AMSU-A 자료 동화가 미치는 영향 분석)

  • Kim, Sung-Min;Kim, Hyun Mee
    • Atmosphere
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    • v.27 no.1
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    • pp.93-104
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    • 2017
  • The effect of Advanced Microwave Sounding Unit-A (AMSU-A) observations on the short-range forecast in East Asia (EA) was investigated for the Northern Hemispheric (NH) summer and winter months, using the Forecast Sensitivity to Observations (FSO) method. For both periods, the contribution of radiosonde (TEMP) to the EA forecast was largest, followed by AIRCRAFT, AMSU-A, Infrared Atmospheric Sounding Interferometer (IASI), and the atmospheric motion vector of Communication, Ocean and Meteorological Satellite (COMS) or Multi-functional Transport Satellite (MTSAT). The contribution of AMSU-A sensor was largely originated from the NOAA 19, NOAA 18, and MetOp-A (NOAA 19 and 18) satellites in the NH summer (winter). The contribution of AMSU-A sensor on the MetOp-A (NOAA 18 and 19) satellites was large at 00 and 12 UTC (06 and 18 UTC) analysis times, which was associated with the scanning track of four satellites. The MetOp-A provided the radiance data over the Korea Peninsula in the morning (08:00~11:30 LST), which was important to the morning forecast. In the NH summer, the channel 5 observations on MetOp-A, NOAA 18, 19 along the seaside (along the ridge of the subtropical high) increased (decreased) the forecast error slightly (largely). In the NH winter, the channel 8 observations on NOAA 18 (NOAA 15 and MetOp-A) over the Eastern China (Tibetan Plateau) decreased (increased) the forecast error. The FSO provides useful information on the effect of each AMSU-A sensor on the EA forecasts, which leads guidance to better use of AMSU-A observations for EA regional numerical weather prediction.

Comparative Analysis of Extracted Snow Cover Area Using Terra MODIS and NOAA AVHRR Imageries for ChungJu Dam Watershed (Terra MODIS 및 NOAA AVHRR 위성영상을 이용한 충주댐 유역의 적설분포 추출 결과 비교분석)

  • Hong, Woo-Yong;Shin, Hyung-Jin;Ha, Rim;Kim, Seong-Joon
    • Proceedings of the Korea Water Resources Association Conference
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    • 2008.05a
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    • pp.1092-1096
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    • 2008
  • 최근 국내에서 저해상도 위성영상을 이용한 적설 분포의 추출연구가 융설과 관련된 수문학적 연구에 이용되기 시작하였다. 한반도와 같이 넓은 지역을 대상으로 추출하는 과정에서 대기에 의한 방해가 너무 큰 영상은 구름 아래 지표면의 정보를 얻을 방법이 없어 해당 날짜의 영상을 제외 할 수밖에 없는 문제가 생긴다. 본 연구에서는 센서의 특성과 영상의 촬영 시간, 그리고 촬영 각도가 달라 서로 다른 대기의 영향을 받는 Terra MODIS 위성영상과 NOAA AVHRR 위성영상을 이용하여 각각의 적설 분포를 추출하는 방법을 비교 연구함으로써 영상을 분석하는데 있어 구름의 영향을 최소화 하고자 하였다. 2004년부터 2006년까지 겨울철의 적설이 발생한 기간을 대상으로 총 3개년의 영상을 분석한 결과를 바탕으로 두 영상으로부터 추출된 적설분포의 차이를 우리나라의 충주댐 유역을 중심으로 비교하였다. 밴드별 파장대의 반사 특성을 이용한 MODIS snow cover와 임계값을 선정하여 구하는 NOAA AVHRR는 서로 다른 적설분포를 보였다고 판단되며, 이는 해상도와 영상 합성, snow cover 추출 알고리즘의 차이 및 대기 현상의 영향 등으로 인하여 추출면적 값이 차이를 보이는 것이라 생각된다. 두 영상에 의한 추출면적의 비교분석 결과, 적설분포의 추출에 있어서 두 영상을 서로 절충하여 사용할 수 있다고 판단된다.

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Relations NOAA/AVHRR SST between Migratory Fishes in the Korean Seas (NOAA/AVHRR SST 자료를 이용한 한반도 주변해역에서의 수온과 어장변화특성 연구)

  • Seo, Won-Chan;Yoon, Hong-Joo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.12
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    • pp.2265-2270
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    • 2008
  • It was studied to the displacement and the amount of catch for migratory fishes with NOAA/AVHRR SST(Sea Surface Temperature) from 1988 to 2000 in the Korean Seas. The analyzed results from SST data showed generally the oceanic warming trend in the Korean Seas. On the increasement of SST, the distributed areas of migratory fishes which living in the warm waters were displaced gradually to the northward directions(high latitude) and then the amount of catch was increased during this studied periods against to migratory fishes which living in the cold waters.

NOAA's Response Plan for Nuclear Emergencies

  • Hwang, Sun-Tae;Choi, Kil-Oung
    • Journal of Radiation Protection and Research
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    • v.25 no.2
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    • pp.115-118
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    • 2000
  • With reference to nuclear emergency information concerning the national emergency plan for nuclear accidents, the response plan for the atmospheric nuclear emergencies of the U.S. National Oceanic and Atmospheric Administration (NOAA) was reviewed and described for introducing an overview on it to the Korean Association for Radiation Protection (KARP).

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