• 제목/요약/키워드: Oyashio

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북서태평양 명태 어장의 해황 - 1 . 해저지형과 해수유동 - (Oceanography in the Waters Adjacent to Kamchatka and Kurile Islands in the Northwestern Pacific - I)

  • 양재목;장선덕
    • 수산해양기술연구
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    • 제13권1호
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    • pp.11-15
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    • 1977
  • 1977~76년에 부산수산대학의 오태산호를 사용하여 북서태평양의 소련 Kamchatka 반도와 Kurile열도 근해에서 해양 관측, 음향 측심 및 해류 조사를 실시한 자료를 해석하고, 해수유동과 해저지형과의 관련성 등에 관하여 검토하였다. Kamchaka 반도 동방의 대륙붕은 넓게 확장되어 그 폭은 약 75km에 달하고 그 경사는 완만하다(1~2。). 이 대륙붕은 Paramushir도 동방에서 폭이 좁아져서 약 36km가 되고 경사가 급해진다. Onekotan만 동쪽 약 20mile 해역에는 대륙붕이 조금 짤라져 해삼 모양의 솟은 곳이 있고, 그 단면은 평두해산과 비슷하다. Kurile열도 동방 Oyashio 해류 유역에서 직접 측류한 결과는 약 1kt로서 해류의 역학계산으로 얻은 유속 0.5~0.7kt 보다 조금 빨랐다. Oyashio 해류 동쪽 가장자리에는 강한 해류와 개속된 대소 규모의 좌선 및 우선 소용돌이가 줄지어 있다.

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Surface Heat Flux and Oceanic Heat Advection in Sendai Bay

  • Yang Chan-Su;Hanawa Kimio
    • 대한원격탐사학회지
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    • 제22권1호
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    • pp.11-24
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    • 2006
  • Coastal sea surface temperature (CSST) and meteorological data from January through December 1995 are used to estimate the net surface heat flux and heat content for Sendai Bay. The average annual surface heat flux in the area north of the bay is estimated to be $+35Wm^{-2}$, whereas the southwestern area is estimated to be $+56Wm^{-2}$. Therefore, the net surface heat flux shows a net gain of heat over the whole bay. The largest heat gain occurs near Matsukawaura, where the strong Kuroshio/Oyashio interaction produces anomalously cold SST and wind is more moderate than in other regions of Sendai Bay over most of the year. The lowest heat gain occurs around Tashiro Island, where the temperature difference between air and sea surface is lower and wind is stronger. The heat budget shows that both surface forcing and horizontal advection are potentially important contributors to the seasonal evolution of CSST in the bay. From the A VHRR and SeaWiFS data, it is found that offshore conditions between the bay and Eno Island are different due to the presence of the Ojika Peninsula. It is also shown that the temporal behaviors of SSTs in the bay are closely connected with the air-sea heat flux and offshore conditions.

Fluctuations of Pelagic Fish Populations in Relation to the Climate Shifts in the Far-East Regions

  • Gong, Yeong;Jeong, Hee-Dong;Suh, Young-Sang;Park, Jong-Hwa;Seong, Ki-Tack;Kim, Sang-Woo;Choi, Kwang-Ho;Han, In-Seong
    • Journal of Ecology and Environment
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    • 제30권1호
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    • pp.23-38
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    • 2007
  • Based on a time series of ocean climate indices and catch records for seven pelagic fish species in the Tsushima Warm Current (TWC) and Kuroshio-Oyashio Current (KOC) regions from 1910 to 2004, we detected regional synchrony in the long-term fluctuations of the fish populations and identified alternation patterns of dominant species related to climate shifts. The annual catches of Pacific herring, Japanese sardines, Japanese anchovies, jack mackerel, chub mackerel, Pacific saury and common squid in the TWC region fluctuated in phase with those in the KOC region, which suggests that they were controlled by the same basin-wide climate forcing. After the collapse of the herring fishery, the alternation sequence was: sardines (1930s), Pacific saury, jack mackerel, common squid and anchovies ($1950s{\sim}1960s$), herring ($late\;1960s{\sim}early\;1970s$), chub mackerel (1970s) and then sardines (1980s). As sardine biomass decreased in the late stages of the cool regime, catch of the other four species increased immediately during the warm period of the 1990s. Regional differences in the amplitude of long-term catch fluctuations for the seven pelagic fishes could be explained by regional differences in availability, fishing techniques and activity.

Changes in MCSST and Chlorophyll-a Off Sanriku Area (38-43N, 141-l50N) from NOAA/AVHRR and SeaWiFS Data

  • Kim, Myoung-Sun;Asanuma, Ichio
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
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    • pp.95-100
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    • 1998
  • The purpose of this study is to describe the change of the spring bloom and oceanographic condition. The variation of pigment concentration derived from the satellite ocean color data has been analyzed. According to the movement of blooming area, blooming was very concerned with a rising trend of sea surface temperature and a supply of nutrients. A nutrient rich water carried by the Oyashio encounters with the warm Core ring, where mixings and blooms are observed. We examined the correlation by using the satellite observations of the temperature and chlorophyll-a for the spring seasons (May, June, July) of 1998 the off Sanriku area (38-43N, 141- l50E). Using the SeaWiFS data, we process the data into the level-3, which contains the geophysical value of chlorophyll-a. And chlorophyll-a data is mapped for the water between 110E and 160E, and 15N and 52N with a 0.08 * 0.05 degree grid for each image. And Sea Surface Temperature (SST) data is produced using the AVHRR onboard the NOAA. The SST is derived by the MCSST. Then, the data is mapped for the water as much as chi-a data. And these gridded image was made by detection of each water masses, which are Kuroshio Extension, the warm-core ring and the Oyashlo Intrusion, etc., using those satellite images to determine short term change. Off Sanriku is a place where warm-water pool and the Oyashio at-e mixed. When warm streamer has intruded in cold water, the volume of phytoplankton increases at the tip of warm streamer. Warm water streamer was trigger of occurring blooming. And also, SeaWiFS images provided as much information for the studies of chlorophyll-a concentrations in the surface.

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The Biology of the Pelagic Amphipod, Primno macropa Guer., in the Western North Pacific: 2. Geographical Distribution and Vertical Distributional Pattern

  • Yoo, Kwang-Il
    • 한국동물학회지
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    • 제15권2호
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    • pp.87-91
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    • 1972
  • 西部 北太平洋에 있어서의 本種에 대한 地理分布와 垂直分布 및 晝夜垂直移動에 관한 知見은 극히 限定된 海域과 深度에 있어서의 報告가 있을 뿐이다. 筆者는 北緯 20度에서 47度에 이르는 東經 50度 以西의 西部 北太平洋과 이의 附屬海에 걸친 광범위한 調査를 통하여 本種의 地理分布에 관한 새로운 知見을 얻었다. 그 結果로 東支那海의 表層을 제외한 68地點에서 本種이 出現함으로써 浮游性 端脚類中에서도 唯一하게 西部 北太平洋 全域에 걸쳐 一樣하게 分布하고 있으며 季節的인 消長이 없음이 究明되었다. 한편 垂直的으로는 0 $\\sim$ 1,500m 以上에 分布하고 있으며 最深採集記錄은 定點 229 $(34^\\circ 44.3'N, 140^\\circ 04.4'E)$에서의 1,650 $\\sim$ 2,220m層에서 얻어졌다. 晝夜垂直移動의 類型을 보면 本種은 晝間에는 深層部에 分布하며 夜間에 表層部로 현저한 晝夜移動을 하고 있음을 밝혔다. 이 移動의 範圍는 100 $\\sim$ 200m에 달한다. 또한 黑潮域에서는 新潮域에 비하여 垂直分布의 深度가 얕으며 서로 垂直分布의 深度와 移動의 範圍가 다르다. 즉 黑潮域에서는 晝間 0 $\\sim$ 200m層에 夜間 100 $\\sim$ 300m層에 個體群의 中心이 分布하며 100m의 範圍로 垂直移動을 하는데 反하여 新潮域에서는 晝間 400 $\\sim$ 700m, 夜間 100 $\\sim$ 500m로 200m의 範圍로 移動한다. 이는 兩海域에 있어서의 個體群의 組成이 서로 다른데 起因되는 결과로 사료된다.

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Interleaving Phenomena of the North Pacific Intermediate Water in the Offshore Area of the Kuroshio

  • Yang, Sung-Kee;Lee, Byung-Gul
    • 한국환경과학회지
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    • 제12권5호
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    • pp.521-527
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    • 2003
  • To study the intruded phenomena of North Pacific Ocean around Boso peninsular, water property distribution in the adjacent seas to Japan is studied using the hydrographic data obtained by Japan Maritime Agency and Japan Fisheries Agency from 1973 to 1996, The scattering of water type in T-5 diagram is relatively small in the Kuroshio Region. Both the envelopes of saline side and of fresh side of the scattered data points shifts gradually from saline side to fresh side as the observation Line moves from southwest to northeast. In mixed water region, the scattering of water type increases rapidly as the observation line moves north; the envelope of fresh cold side moves towards fresh cold side much faster than that of saline side. This suggests that the water does not advect along the salinity minimum layer, but the salinity minimum layer can be understood as a boundary of two different waters aligned vertically, We defined the typical water masses as the Oyashio Water and the Kuroshio Water. The water mass below the salinity minimum layer may be created by isopycnal mixing of these two water masses with a fixed mixing rate. While the water mass above the salinity minimum cannot be created simply by isopycnal mixing. The salinity minimum layer may be eroded from upper side due to active minxing processes in the surface layer, while the water of the salinity minimum layer moves gradually southward. This appears to give an explanation why the thermosteric anomaly value at salinity minimun decereases towards south.

THE STUDY OF SPATIAL AND TEMPORAL VARIABILITY OF THE KUROSHIO EXTENSION USING REMOTE SENSING DATA WITH APPLICATION OF DATA-FUSION METHODS

  • Kim Woo-Jin;Park Gil- Yong;Lim Se-Han;OH Im-Sang
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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    • pp.434-436
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    • 2005
  • Analysis method using remote sensing data is one of the effective ways to research a spatial and temporal variability of the mesoscale oceanic motions. During past several decades, many researchers have been getting comprehensive results using remote sensing data with application of data fusion methods in many parts of geo-science. For this study, we took the integration and fusion of several remote sensing data, which are different data resolution, timescale and characteristics, for improving accurate analysis of variation of the Kuroshio Extension. Furthermore, we might get advanced ways to understand the variability of the Kuroshio Extension, has close relation to the spatial and temporal variation of the Kuroshio and Oyashio Current.

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ONE TYPE OF EDDY DEVELOPMENT IN THE NORTHEASTERN KUROSHIO BRANCH

  • Bulatov, Nafanail V.;Kapshiter, Alexander V.;Obukhova, Natalya G.
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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    • pp.926-929
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    • 2006
  • Some features of vertical structure of the frontal interaction zone of the warm Kuroshio Current and cold Oyashio Current are known from 1930 from analysis of ship data. Ship data however do not allow carrying out the area detailed survey opposite to satellite infrared (IR) observations which possess by high spatial and temporal resolution. Analysis of NOAA AVHRR IR images demonstrated that process of formation and development of the Kuroshio warm core rings is highly complex. They are formed as a result of development of anticyclonic meanders of the warm Kuroshio waters and spin off them from the current. Joint analysis of thermal infrared images and altimetry data has also indicated that interaction of eddies to the frontal zone plays a crucial role in formation of large eddies moving to the Southern Kuril region.

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북서태평양에서의 북태평양중층수 (North Pacific Intermediate Water in the Northwest Pacific)

  • 양성기
    • 한국환경과학회지
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    • 제3권3호
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    • pp.229-239
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    • 1994
  • 북태평양에 위치한 일본근애의 수괴분포에 대한 특성을 중층수에 중점을 두어 일본 해상 기상청이 관측한 정이 해양관측정선에서 얻어진 자료를 사용하여 검토하였다. 쿠로시오해역의 T-S도상에서 분산은 비교적 작게 나타나고 있다. 쿠로시오해역에서 고온, 고염분층에서부터 저온, 저염분측으로 이동하고 있다. 혼합해역에서 수형의 분한은 북으로 이동함에 따라 고염분측의 이동보다 저온, 저염분측으로 급격히 증가하고 있다. 염분극소층에서 해수의 써모스테릭 아노말리(thermosteric anomaly)는 해양관측정선이 북에서 남으로 이동함에 따라 감소하고 있다. 이러한 사실은 해수가 염분극소층을 따라 남하하는 것이 아니고, 염분극소층이 두 해수의 수직적인 경계임을 제시하고 있다. 여기서 오야시오수와 쿠로시오수의 두 전형적인 수괴를 정의하고 있따. 염분극소층보다 깊은 부분의 T-S도는 전형적인 오야시오수와 쿠로시오수가 같은 양으로 혼합하는데 대해, 염분극소층보다 상층에서는 전혀 다름 양상을 나타내고 있다. 염분극소층 해수의 써모스테릭 아노말리가 북에서 남으로 이동함에 따라 뚜렷이 감소해 간다. 이러한 사실은 왜 염분극소층에서 써모스테릭 아니말리의 값이 북에서 남쪽으로 이동함에 따라 감소하는지를 설명해 주고 있다.

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Gymnodinioid Dinoflagellates (Gymnodiniales, Dinophyceae) in the Open Pacific Ocean

  • Gomez, Fernando
    • ALGAE
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    • 제22권4호
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    • pp.273-286
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    • 2007
  • Records of selected gymnodinioid dinoflagellates from the open waters in the vicinity of the Kuroshio and Oyashio Currents, the Philippine, Celebes, Sulu and South China Seas, western and central equatorial and southeast Pacific Ocean are described and illustrated. The species Gymnodinium fusus Schütt, Gyrodinium falcatum Kofoid et Swezy, G. caudatum Kofoid et Swezy, G. sugashimanii J. Cachon et al. and Pseliodinium vaubanii Sournia are considered to be morphotypes of a single species, that until further studies can establish the correct genus, are named G. falcatum. This study is the first to record individuals of G. falcatum with very long curly extensions. Other gymnodinioid dinoflagellates that showed bifurcated hyposomes may be related to Gyrodinium bifurcatum Kofoid et Swezy or cells of thecate dinoflagellates exuviated from their thecae. Some specimens showed a rigid cover, although no discernible thecal plates. In this group, the most common species was Ptychodiscus noctiluca Stein and, for the first time, a micrograph of a tentative specimen of the genus Berghiella Kofoid et Michener is reported. The validity of the genera Berghiella and Balechina Loeblich Jr. et Loeblich III with thick cell covers is discussed. Several species with apical extensions, other unknown taxa with distinctive shapes, and colonial forms are illustrated. The diversity of gymnodinioid dinoflagellates is underinvestigated in the open ocean.