위성원격탐사를 활용한 해양표면 바람장 자료 분석

윤홍주,Yoon, Hong-Joo 한국정보통신학회 2008 한국정보통신학회논문지 Vol.12 No.1

SAR의 마이크로파를 이용하면 악기상환경 및 주야간에도 해양의 관측이 가능하다. SAR의 해양표면에 대한 영상은 표면바람장과 관련된 대기 현상에 관한 많은 정보를 가지고 있다. SAR로부터 추출되는 풍속의 정보는 다양하게 이용된다. SAR 영상으로부터 해상풍을 산출하기 위해서는 바람산출모델에 SAR 영상으로부터 추출한 풍향 자료와 후방산란계수 값을 입력하여 풍속을 산출한다. 이 때 풍속은 CMOD5 모델에 풍향의 값을 적용하여 추할 수 있다. CMOD5 모델에 사용할 Azimuth angle 값은 SAR 자료로부터 구해지는 Look angle 값에 $90^{\circ}$를 더 함으로써 구해진다. SAR 영상으로부터 구한 파향 스펙트럼 은 항상 파향에 있어서 $180^{\circ}$의 상반된 두 정점을 보여주는데 이는 영상에 적용한 2차원 FPT의 결과이다. 파향에 있어서의 이러한 모호성은 육지의 위치라든지, 바람의 방향 혹은 수치모델 결과 등을 이용하여 결정하여야 한다. 이러한 2D-FFT를 통해 구해진 풍향은 실측자료와 $3^{\circ}{\sim}7^{\circ}$ 정도의 차이를 나타내고 있다. CMOD5 모델을 통해 얻어진 풍속의 값은 각각 실측자료와 2m/s 이하의 유사한 값들을 나타냈다. If we use the microwave of SAR, we can observe ocean in spite of severe weather or night time. The sea surface image of SAR has numerous information about atmospheric phenomena related to surface wind field. The extracted wind information from SAR can be used diversely. In order to extract sea wind speed from SAR image, a generated wind direction from SAR and sigma nought should be input into wind model. Therefore, wind speed can be obtained by input wind direction into CMOD5 Model. Azimuth angle using CMOD5 Model is generated by added $90^{\circ}$ to Look angle which is extracted from SAR data file. A gained wind direction spectrum from SAR image has $180^{\circ}$ ambiguity because of 2D-FFT. This ambiguity should decide to use the location of land, wind direction in field or the result of numerical model. Consequently, wind direction using 2D-FFT is $3^{\circ}{\sim}7^{\circ}$ differences with actual surveying data. Wind speed by CMOD5 model is similar to actual surveying data as below 2m/s.

적조기상정보 : 기상인자를 활용한 연안 적조예측기술 개발

윤홍주,Yoon Hong-Joo 한국정보통신학회 2005 한국정보통신학회논문지 Vol.9 No.4

본 연구는 연안기상 정보를 효율적으로 이용하여 사전에 적조를 예찰하고 실용화하여 적조로부터의 재해를 저감하는데 있다. 이러한 적조예찰을 위해서는 기본적으로 우리나라 주변 해역의 적조발생에 관여하는 기상 및 해양인자들의 환경학적 특성을 파악하고 이들의 상관성으로부터 적조발생 가능성을 예측하는 정보를 제공하는 것이 매우 중요하다. 또한 이러한 정보를 공공의 활용에 쉽게 이용될 수 있게끔 정보시스템을 구축하는 것이 필요하다. 앞으로 본 연구의 결과는 이 분야에 관련되는 학계, 공공기관, 업계의 종사자들에게 유용한 정보로 활용될 것으로 기대되며 그리고 매년 연례행사처럼 국가적으로 문제시 되고 있는 우리나라 주변해역의 적조피해를 줄이는데 실질적으로 기여할 것이다. Red tide(harmful algae) in the Korean Coastal Waters has a given a given damage to the fishery every year. However, the aim of our study understands the influence of meteorological factors (air and water temperature, precipitation sunshine, solar radiation, winds) relating to the mechanism of red tide occurrence and monitors red tide by satellite remote sensing, and analyzes the potential area for red tide occurrence by GIS. The meteorological factors have directly influenced on red tide formation. Thus, We want to predict and apply to red tide formation from statistical analyses on the relationships between red tide formation and meteorological factors. In future, it should be realized the near real time monitoring for red tide by the development of remote sensing technique and the construction of integrated model by the red tide information management system (the data base of red tide - meteorological informations. Finally our purpose is support to the prediction information for the possible red tide occurrence by coastal meteorological information and contribute to reduce the red tide disaster by the prediction technique for red tide.

SAR자료를 이용한 해상풍 산출 및 현장 자료간의 비교.검정

윤홍주,박광순,김상익,Yoon Hong-Joo,Park Kwang-Soon,Kim Sang-Ik 한국정보통신학회 2006 한국정보통신학회논문지 Vol.10 No.4

본 연구에서는 SAR영상을 통해 해상풍 산출한 다음 해양연구원의 실시간 해양 해양기상 관측 자료와 비교 분석하여 그 정확도를 한반도 주변해역을 대상으로 파악하였다. SAR를 통해 추출된 해상풍 자료와 실측값의 RMS는 풍속은 0.8m/s, 풍향은 8도로 나타났다. 전체 적으로 실측값과 많은 차이를 보이지는 않지만 FFT 방법에 의한 SAR 영상의 바람 띠를 분석하기 위해서는 최소 10km 이상의 영상을 사용하여야만 하였다. 또한 본 연구에서는 우리나라 연안의 Radarsat SAR 영상을 이용하여 바람산출모델 CMOD5를 통해 해상풍 값을 산출하였다. CMOD5는 현재까지 산란계(Scatterometer)와 ERS SAR 위성을 이용해 해상풍을 산출할 때 가장 많이 사용되어오던 CMOD4 모델을 개선한 모델로써 특히 고풍속일 때의 결과에서 많은 개선을 보였다. In order to retrieve ocean wind from SAR() image, and to estimate and validate between SAR-derived wind and in-situ wind, with RADAR SAR ocean images and real time marine meteorological data. It was used images with more than 10km to analyze the band of wind in SAR image by FFT(First Fourier Transformation) method and was used CMOD5 as wind retrieval model to retrieve ocean wind. In this study, generally it showed good results as RMS presented 0.8m/s for speed and 8 degree for direction, and especially when wind was hish speed, it presented very good results.

Topex / Poseidon 위성 고도계 자료에 대한 신호처리 및 한반도 주변해역에 대한 그 적용

윤홍주(Hong Joo Yoon) 한국지리정보학회 1999 한국지리정보학회지 Vol.2 No.1

Topex/Poseideon staelite altimetric data are used to estimate characteristics on the oceanic and atmospheric correction factors, and th mean sea level and its variations in the Yellow Sea, the East China Sea and East Sea from September 1992 through August

총설 : 위성원격탐사와 지구과학 -위성해양학-

윤홍주 ( Hong Joo Yoon ) 대한원격탐사학회 1999 대한원격탐사학회지 Vol.15 No.1

Today, satellite remote sensing plays an important role as a advanced science and technology, and becomes a superpower tool of the study and research in various fields of Earth Science. UN proclaimed that 1998 was the year of the oceans, and WMO chose the title of `Weather, Ocean and Human activity` as the principal subject of the day of the world meteorology in march 23, 1998, respectively. As previously announced, these two memories give the great meaning for satellite remote sensing in oceanography. Therefore, this study reviews satellite oceanography for many specialists in the fields of the ocean and fishery science. In future, satellite oceanography will be greatly used to observe, monitor and predict various phenomena associated with the oceans, in order to seek safety in a natural disaster, and menage and conserve the oceanic environments and resources.

Topex/Poseidon 위성의 Altimeter자료를 이용한 남인도양의 환경보정인자 특성에 관한 연구

윤홍주 ( Hong Joo Yoon ),김영섭 ( Young Seup Kim ),이재철 ( Jae Chul Lee ) 대한원격탐사학회 1998 대한원격탐사학회지 Vol.14 No.2

Topex/Poseidon satellite, lanuched in Auguest 1992, has provided more 5 years of very good quality data. Efficient improvements, either about instrumental accuacy or about sea level data correction, have been made so that Topex/Poseidon has become presently a wonderful tool for many researchers. The first mission data of 73 cycles, September 1992-August 1994, was used to our study in order to know characteristics of environmental correction factors in the Amsterdam-Crozet-Kerguelen region of the South Indian Ocean. According to standard procedures as defined under user handbook for sea surface height data processes, then we have chosen cycles 43 as the cycle of reference because this cycle has provided the completed data for measurement points and has presented the exacted position of ground track compared to another cycles. It was computed variations of various factors for correction in ascending ground track 103(Amsterdam-Kerguelen continental plateau) and descending ground trackl70(Crozet basin). Here the variations of ionosphere, dry troposphere, humid troposphere, electromagnetic bias, elastic tide and loading tide were generally very smaller as a few of cm, but the variations of oceanic tide(30-35cm) and inverted barometer(15-30cm) were higher than another factors. For the correction of ocean tide, our model(CEFMO: Code d` Elements Finis pour la Maree Oceanique)-This is hydrodynamic model that is very well applicated in all oceanic situations-was used because this model has especially good solution in the coastal and island area as the open sea area. Conclusionally, it should be understood that the variation of ocean free surface is mainly under the influence of tides(>80-90%) in the Amsterdam-Crozet-Kerguelen region of the South Indian Ocean.

위성 자료를 이용한 제주도 주변해역에 나타나는 중국대륙기원 양자강 유출수(저염수)에 관한 연구

윤홍주 ( Hong Joo Yoon ),조한근 ( Han Keun Cho ) 한국지리정보학회 2005 한국지리정보학회지 Vol.8 No.4

위성자료와 경험직교함수를 이용한 제주도 주변해역의 중국대륙연안수 영향 연구

윤홍주 ( Hong Joo Yoon ),조한근 ( Han Keun Cho ),안유환 ( Yu Hwan Ahn ) 대한원격탐사학회 2005 대한원격탐사학회지 Vol.21 No.6

China Coastal Waters (CCW) usually appears in the seas surrounding Jeju Island annually(June to October) and is very pronounced in August. Generally, low-salinity water appears to the western seas of Jeju Island from June through October and gradually propagates to the eastern seas, where CCW meets the Tsushima Current. Empirical orthogonal function (EOF) analysis of SLAs and SSTs indicated that the variance in SLAs and SSTs was 95.05%(the first mode to third mode) and 98.09%(the first mode), respectively. The PSD of the western waters for the first mode of EOF analysis of SLAs was stronger than that of the eastern waters because of the influence of CCW. The PSD for the EOF analysis of SSTs was similar in all areas (the Yangtze Estuary and the seas to the west and east of Jeju Island), with a period of approximately 260 days.

한국 연안에서의 적조형성과 기상인자간의 상관성에 대한 통계학적 해석 및 위성에 의한 적조 모니터링

윤홍주 ( Hong Joo Yoon ),김형석 ( Hyeong Seok Kim ) 한국어업기술학회 2005 수산해양기술연구 Vol.41 No.2

복합위성자료(Topex/Poseidon, ERS1)를 이용한 남인도양의 해수면 변화와 와동류 연구

윤홍주 ( Hong Joo Yoon ),서영상 ( Young Sang Suh ) 대한원격탐사학회 2003 대한원격탐사학회지 Vol.19 No.4

Sea level variability and eddy in the Amsterdam-Crozet-Kerguelen region of the South Indian Ocean were studied during 1 year (October 15, 1992~October 15, 1993) using multi-satellite data(Topex/Poseidon, ERS1) produced by signal treatment. We found that sea level variabilities (>10cm) generally exist along the Antarctic Circumpolar Current in the area of 35°~46°S and strong sea level variabilities (20~30cm) were especially occurred from the effects of eddy due to bottom topography in two small area: 49°~57°E and 38°~42°S, and 58°~64°E and 42°~44°S.