• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.54-57
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• 2005

This study examines moisture supplement from the warm ocean in snowfalls of two cases and heavy rainfall of Typhoon case. The QuickSCAT wind is used to evaluate the convergence of moisture fluxes in the storms from the sea in estimation of the amount of heavy snowstorm and rainfall. The results show that enough water vapor transport from ocean to atmosphere induced the severe storms, because strong QuickSCAT -derived vertical velocity nearly concurred with heavy snowfall and rainfall. In the present study, we attempted to show that QuickSCAT wind can be used to forecast the severe weather events, such as heavy snowfall and rainfalls.

• Proceedings of the KSRS Conference
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• 2006.03a
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• pp.337-340
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• 2006

태풍의 경우, 주요 자연재해 중의 하나로 태풍의 상황을 정확하게 파악하는 것은 기상예측의 정도를 높이고, 재해를 방지하는데 중요한 역할을 할 수 있다. 일반적으로 태풍의 동향을 감시하는데 있어, 히마와리 등의 기상위성이 주로 활용되고 있다. 근년 인공위성의 원격탐사를 이용하여 광범위의 해양에 대한 해상풍과 파랑의 관측이 가능하게 되었다. 본 연구에서는, QuickSCAT위성에 의한 해상풍 관측의 현상을 조사하고, 위성으로부터 얻어진 2000년의 데이터를 사용해서 한반도 주변해역에 대한 해상풍의 월변동 특성을 조사하고, 2000년 7월에 한반도에 영향을 준 태풍 카이탁내의 해상풍을 검토하였다. 추가로 RSMC 동경 태풍 센터에서 발행하는 태풍자료를 이용하여, 태풍 비교를 수행하였다. 풍속은 제주도 주변해역, 특히 제주도 동쪽해역에서의 풍속이 연중 강하며, 9월에서 2월 기간에는 북풍 계열의 바람이 우세하고, 6월-8월에는 남풍계열의 바람이 지배적이다. 봄의 기간인 3월-5월에는 북풍에서 남풍으로 바뀌는 과정으로 다양한 방향의 바람이 혼재한다. 태풍 카이탁의 해상풍 조사를 통하여, 위험반원의 형상이 보다 복잡하며 그 범위가 크다는 점이 확인되었다.

• Atmosphere
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• v.19 no.2
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• pp.145-154
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• 2009

This study compared the sea surface wind pattern between model results from KMA operational model (RDAPS) and retrieved results from QuickSCAT in the 2006-2007 year. The mean spatial distributions of sea surface wind of RDAPS and QuikSCAT show the prominent seasonal patterns of summer and winter season adjacent to Korean Peninsular. The magnitude of sea surface wind predicted by RDAPS is weaker than that of QuikSCAT in most north Pacific ocean. In summer of 2006 positive bias with the maximum of 1 m/s is appeared in broad region of north Pacific ocean, however. the positive bias region is decreased to small region in 2007. Even though the predicted sea wind by RDAPS is stronger(weaker) than observed one by QuikSCAT in summer (winter), the RDAPS model simulate well the sea surface wind adjacent to Korean peninsular.

• Proceedings of KOSOMES biannual meeting
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• 2006.11a
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• pp.201-204
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• 2006

태풍의 경우, 주요 자연재해 중의 하나로 태풍의 상황을 정확하게 파악하는 것은 기상예측의 정도를 높이고, 재해를 방지하는데 중요한 역할을 할 수 있다. 일반적으로 태풍의 동향을 감시하는데 있어, MTSAT 등의 기상위성이 주로 활용되고 있다. 근년 인공위성의 원격탐사를 이용하여 광범위의 해양에 대한 해상풍과 파랑의 관측이 가능하게 되었다. 본 연구에서는, 2000년 QuickSCAT위성에 의한 해상풍의 월변동 특성을 조사하고, 7월에 한반도에 영향을 준 태풍 카이탁내의 해상풍을 검토하였다. 추가로 2005 년 8월 30일의 태풍 탈림에 대해서 ENVISAT ASAR Scan SAR에 의한 해상풍 추출을 시도하였다. QuickSCAT 에 의한 풍향을 이용한 방법과 SAR 자체의 패턴을 이용한 방법이 비교되었다.

• Korean Journal of Remote Sensing
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• v.16 no.4
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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.

• Atmosphere
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• v.12 no.4
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• pp.43-55
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• 2002

기상청의 위성기상업무는 위성자료를 취득하여 위성영상 및 기상분석정보를 생산하고, 예보관을 비롯한 자료 사용자들에게 자료를 신속하게 제공함으로써 체계적인 위성자료 활용서비스를 수행하는 것이다. 최근 외국의 우주개발 동향과 관련하여 활용 가능한 위성자료가 증가함에 따라 위성자료 활용시스템 개선을 추진해 왔으며, 2002년 현재 종래의 GMS, NOAA 이외에 Meteosat-5, FY-2B, FY-1C, Terra, QuickScat, DMSP, TRMM, SeaWiFS 등의 다양한 위성자료를 활용하고 있다. 예보현업에 대한 원격탐사자료 지원업무는 24시간 근무체계로 위성수신분석장비를 안정적으로 운영하면서 각종 위성정보를 종합적으로 활용하여 기상실황의 변화를 감시하고, 특히 전선, 저기압, 태풍에 동반된 구름의 변화상황, 황사의 발생 및 이동 등에 대한 상황을 파악하고 있다. 또한 위성자료의 보존관리 및 외부기관으로부터의 위성자료 요청에 대한 지원업무도 중요한 업무의 하나로 수행하고 있다. 위성정보 활용체계를 강화하기 위해, GMS-5호 위성의 관측임무를 대체하게 될 GOES-9, MTSAT-1R 위성의 자료수신 및 활용체계 구축을 준비하고 있으며, Terra, Aqua와 같은 첨단 지구관측위성자료를 이용한 기상정보 산출기술의 개발을 단계적으로 추진할 것이다.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.463-466
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• 2009

The numerical simulation optimized by Four Dimensional Data Assimilation (FDDA) with Quick Scatterometer (QuikSCAT) data is carried out to evaluate wind resource characteristics at various heights in the southeastern area of the Korean Peninsula, where wind farms are planned to be built on on- and off-shore as well as comparable diurnal wind variations are characterized at the surface. The temporal and spatial distributions of modeled wind speeds showed good agreement with the observations based on the temporal variation analysis. Model results indicate that the higher model is performed in resolution, the more precise results is at turbine hub height. Occasionally, wind speed variations for each numerical resolution has a different regional and seasonal variations. In the coast area, hub height wind speed of 9km-resolution is simillar to that of 3km-resolution. On the other hand, hub height wind speed of 3km-resolution is simillar to that of 1km-resolution in the Jiri mountainous area.

• Ocean and Polar Research
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• v.36 no.2
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• pp.103-110
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• 2014

A wind-driven current in the East Sea from Lagrangian measurements of wind and current at 15 m using MiniMet drifters was analyzed. Spectral analysis of the current from 217 pieces of a 10 day-long time series shows the dominant energy at the inertial frequency for the current at 15 m. Wind has energy peaks at a 0.2-0.5 cycles per day (cpd) frequency band. The power spectrum of the clockwise rotating component is predominant for the current and was 1.5-2 times larger than the anticlockwise rotating component for wind. Co-spectra between the wind and current show two peak frequency bands at subinertial frequency and 0.5-0.3 cpd. Coherences between the wind and current at those peak frequencies are significant with 95% confidence and phase differences were $90-100^{\circ}$. From the phase differences, the efolding depth is estimated as 17 m and this e-folding depth is smaller than the estimation by Chereskin's (1999) 25 m using a moored Acoustic Doppler Current Profiler and an anemometer installed at the surface buoy. The angle between the wind-driven current (or ageostrophic current) and wind from this study was also much larger than the global estimate by Rio and Hernandez (2003) using reanalysis wind and drifters. The possible explanation for the discrepancy comes from the fact that the current is driven by a wind of smaller length scale than 250 km but the satellite or the reanalysis products do not resolve winds of length scale smaller than 250 km. Large rms differences between Mini-Met and QuickSCAT wind on spatial lags smaller than 175 km substantiate this explanation.

• Journal of the Korean Society of Marine Environment & Safety
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• v.15 no.4
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• pp.283-288
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• 2009

Estimations of oil slick area after M/T Herbei Sprit accident in December 2007 were analyzed using ENVITSAT ASAR(Advanced Synthetic Aperture Radar) microwave and KOMPSAT-2 of high resolution data. Monthly end short-term variations of chlorophyll a concentration before end after M/T Herbei Sprit oil spill accident were also analyzed using SeaWiFS/MODIS ocean color data. The oil slick areas estimated by KOMPSAT-2 and ASAR satellites were 59,456 $m^2$ and 1,168 $km^2$, respectively. The winds before end after oil spill accident were prevailed the northerly and northwesterly winds, and the strength of wind in this accident was stronger than 10 m/sec. In Taean and Anmeon-do, monthly mean chlorophyll a concentrations(6.3 mg/$m^3$ and 3.7 mg/$m^3$) in January 2008 alter the oil spill were higher than those(2.9 mg/$m^3$ and 2.5 mg/$m^3$) in December 2007. Short-term variations of chlorophyll a in these areas were decreased alter one or two weeks of oil spill.

• Korean Journal of Remote Sensing
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• v.26 no.4
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• pp.421-437
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• 2010

Surface particulate organic carbon (POC) concentration estimated from Maximum Normalized Difference Carbon Index (MNDCI) algorithm using SeaWiFS data is used to determine spatial and temporal variations of the Changjiang Diluted Water (CDW) in the East China Sea. 10-year monthly POC concentrations (1997-2007) show clearly seasonal variations. Inter-annual variation of POC in whole and three different areas separated by standard deviation is not linearly correlated with the Changjiang River discharge that has decreased after 1998. To determine more detailed spatial and temporal POC variations, we used empirical orthogonal function (EOF) analysis in summer (Jun.-Sep.) from 2000 to 2007. First mode is spatially and temporally correlated with the area influenced by the Changjiang River discharge. Second mode is temporally less sensitive with the Changjiang River discharge but spatially correlated with north-south patterns. Relatively higher POC variations during 2000 and 2003 were shown in the southern East China Sea. These patterns during 2004 and 2007 moved to the northern East China Sea. This phenomenon is better related to spatial variations of wind-direction than the amount of Changjiang River discharge, which is verified from in-situ measurement.