• Title/Summary/Keyword: Radar-echo

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Fundamental Study on the Migrating Course of Fish Around the Set Net - The Bottom Contour Contour and the Tidal Current around Set Net - (정치망어장의 어도형성에 관한 기초연구 ( 2 ) - 해저지형의 해수유동-)

  • Lee, Ju-Hui;Yeom, Mal-Gu;Park, Byeong-Su
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.24 no.1
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    • pp.12-16
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    • 1988
  • The observation of the tidal current and the bottom contour around the set net fishing ground were carried out at four different regions of the southern part of Korea in order to obtain the basic information on the migrating course of fishes. The bottom contour was surveyed with portable echo sounder, and the tidal current was observed by two different methods at the same time. One was 25 hour observation at the fixed position with self-recording current meter (Inter Ocean Model 135 type) and the other was the drift observation of radar reflectors. Most of the set nets have been set near bottom valleys. It was regarded that the fish school became to dense easily near the valley according to the combined effect of the tidal current and the bottom contour.

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Sounding Observation with Wind Profiler and Radiometer of the Yeongdong Thundersnow on 20 January 2017 (2017년 1월 20일 영동 뇌설 사례에 대한 연직바람관측장비와 라디오미터 관측 자료의 분석)

  • Kwon, Ju-Hyeong;Kwon, Tae-Yong;Kim, Byung-Gon
    • Korean Journal of Remote Sensing
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    • v.34 no.3
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    • pp.465-480
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    • 2018
  • On 20 January 2017, the fresh snow cover which is more than 20 cm, accompaning with lightning occurred over Yeongdong coastal region for the first 3-hour of the heavy snowfall event. This study analyzed sounding observations in the heavy snow period which were including the measurements of wind profiler, radiometer and rawinsonde. The features examined from the vertical wind and temperature data at the two adjacent stations, Bukgangneung and Gangneung-Wonju National University, are summarized as follows: 1) The strong (30-40 kts) north-east winds were observed in the level from 2 to 6 km. The Strong atmospheric instability was found from 4 to 6 km, in which the lapse rate of temperature was about $-18^{\circ}C\;km^{-1}$. These features indicate that the deep convective cloud develops up to the height of 6 km in the heavy snowfall period, which is shown in the satellite infrared images. 2) The cooling was observed in the level below 1 km. At this time, the surface air temperature at Bukgangneung station decreased by $4^{\circ}C$. The narrow cooling zone estimated from AWS and buoy data was located in east-west direction. These are the features observed in the cold front of extratropical cyclone. The distributions of radar echo and lightning also show the same shape in east-west direction. Therefore, the results indicate that the Yeongdong thundersnow event was the combined precipitation system of deep convective cloud and cold frontal precipitation.