• 한국수산과학회지
• /
• 제30권6호
• /
• pp.974-983
• /
• 1997

The Okhotsk Sea is unique natural object with climatic peculiarities. The climate of the Okhotsk Sea results from the general distribution of solar radiation during a year, and the characteristics of the atmospheric circulation that varies through a year: In cold half year the main pressure formations are Siberian high and Aleutian low. Asian low centered on Afghanistan dominates over the Asian continent in summer. The North-Pacific sea surface is under effect of permanent North Pacific high. The changes in their position from year to year are very significant. The anticyclonic activity over the Far Eastern Seas is one of the main factors for the formation of weather anomalies over the adjacent territories. The analysis of summer weather characteristics over the coast of Okhotsk and East Sea using the data obtained from Hydrometeorological stations during $1949\~1990$ showed that, to a great extent, distribution of the air temperature depends on thermal state of the Okhotsk Sea and atmospheric circulation over it. We show some relations between weather characteristics and the intensity of atmospheric action center for the North Pacific high in summer when its ridge propagates to Okhotsk Sea. Correlation coefficients between air pressure over the Okhotsk Sea and air temperature for the coastal areas reach up to 0.7. Analysis of the spatial-temporal distribution of main meteorological values over the Okhotsk Sea such as air pressure, and air temperature are also performed.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2006년도 추계학술대회
• /
• pp.47-49
• /
• 2006

The Sea of Okhotsk is the unique area providing the highest methane production rate of the northern hemisphere. The area of focused fluid venting offshore the NE Sakhalin continental slope was investigated during the CHAOS (Hydro-Carbon Hydrate Accumulations in the Okhotsk Sea) expeditions onboard of RV "Akademik Lavrentyev" In 2003, 2005 and 2006. The International Research Project CHAOS (Russia-Korea-Japan) aimed at the study of gas hydrate formation processes associated with the fluid venting in the Sea of Okhotsk. Several new gas hydrate accumulations were discovered during the cruise. Hydrate-associated structures have been named as KOPRI, VNIIOKeangeologia, POI and KIT (the names of cruise participant institutes) Some of hydrate-bearing cores contain big amount of gas hydrates: massive gas hydrate layers (up to 35cm thick) were recovered. The shallowest submarine gas hydrate accumulations in the world (at the depth less then 400m) were discovered during the cruise.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
• /
• pp.913-916
• /
• 2006

Spatial distribution, seasonal and interannual variability of chlorophyll a concentration in Okhotsk Sea from SeaWiFS data between 2001 and 2004 were describe. An Empirical Orthogonal Function method was applied for analysis data. The ten modes described about 85% of total variance. Two maxima were defined - more intensive in spring and weaker in autumn. The first mode showed zones with chlorophyll a concentration during maximum bloom. The second mode specified timing of spring bloom in various regions in Okhotsk Sea. Analysis of SeaWiFS data indicated connection between highest chlorophyll a concentration and sea surface temperature limits during spring bloom. Similar relation was not found during fall bloom.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 1999년도 Proceedings of International Symposium on Remote Sensing
• /
• pp.456-461
• /
• 1999

It is very important for monitoring the interannual variability of sea ice extents in the Okhotsk Sea because the global warming has firstly appeared around the Okhotsk Sea, locating around the southernmost region of sea ice cover in the Northern Hemisphere. In order to develop the sea ice concentration algorithm by microwave sensors onboard satellite, electromagnetic properties of sea ice in the Okhotsk Sea, therefore, were observed by airborne microwave radiometer (AMR), which has the same frequencies as AMSR (Advanced Microwave Scanning Radiometer), ADEOS-II, launching on November, 2000. On this study, it is discussed how to make the image of AMR-EFOV and the video image with nadir angle under flight at the same time, and superimpose the brightness temperature data by AMR-EFOV on the video mosaiced images. For comparing SPOT image, it is clearly that the variation of brightness temperature is small in 89GHz V-pol without the sea ice types and increase at the lower frequency-band.

• Ocean and Polar Research
• /
• 제24권2호
• /
• pp.147-152
• /
• 2002

Seasonal and interannual variation of volume transport through the La-Perouse Strait were estimated using the difference of sea level observed at Krillion of Sakhalin, Russia, and Wakkanai of Hokkaido, Japan, during the period of 1975-1988. Historical sea level measurements between Russian and Japanese tide gauge data were normalized using an independent direct volume transport measurement. Volume transport from the East Sea (Sea of Japan) to the Sea of Okhotsk varied from -0.01 to 1.18 Sv with an annual mean value of 0.61 Sv. Monthly water transport rates showed a unimodal distribution with its maximum occurring in summer (August) and minimum in winter (December-February). The annual mean volume transport varied from 0.2 to 0.8 Sv during the period of 1975-1988 with the maximum variance of 0.6 Sv.

• ALGAE
• /
• 제27권3호
• /
• pp.139-153
• /
• 2012

The re-examination of morphological and anatomical characters of Laminaria appressirhiza and L. inclinatorhiza collected from different localities in the Sea of Okhotsk was performed. Despite their commercial and ecological importance to the region they have not been comprehensively reviewed since their first description in 1970. Our results show that some original diagnostic key characters (e.g., shape of holdfast, shape of sporangial sori, and dissection of blade) are not stable and have deviations from the type morphology when plants grow in different environments. In L. inclinatorhiza, the sporangial sori development occurred differently to the pattern indicated in original species description as they did not develop simultaneously on both sides of the blade. Instead, the sporangial sori outlines on both sides of the blade did not coincide at first and only became coincident later. Also, a deep-water population of L. inclinatorhiza with an unusual and interesting morphology, growing at depths of 15-25 m on opened rocky coasts in Taujskaya Bay (northern part of the Sea of Okhotsk) was found. The stable diagnostic key characters to distinguish these two species are the cone-like, multilayered, very thick and massive holdfast (in L. inclinatorhiza) and rolled margins of blades, lamellar rosette-like part of thallus, and sporangial sori developing only on one side of the blade (in L. appressirhiza). The ecological characteristics, distribution, and abundance of both species in the Sea of Okhotsk are discussed. Both species are perennial and widely distributed in the region. L. appressirhiza is more often found as a subdominant species among other kelps, forming maximum biomass and density of 7-9 kg and 8-25 plants per $1m^2$, respectively. L. inclinatorhiza sometimes forms local mono-species communities with maximum biomass and density of 10-12 kg and 10-15 plants per $1m^2$, respectively.

• 대한지리학회지
• /
• 제46권1호
• /
• pp.36-49
• /
• 2011

본 연구에서는 오호츠크해고기압이 한반도에 영향을 미치는 날과 강도의 변화를 규명하고자 하였다. 지상 일기도와 기상자료, 재분석자료 등을 분석하여 다음과 같은 결과를 얻었다. 4월의 주변 육지기온이 높은 해일수록 오호츠크해고기압의 첫 출현일이 일러지는 경향이다. 최근 오호츠크해고기압의 출현일수는 감소하였으며, 그 강도는 6월 해수면온도와 주변 육지기온의 차이가 클수록 강해지는 경향이다 4 5월, 6월, 7월의 오호츠크해고기압 출현일수는 주변 육지기온이 상승할수록 증가하며, 해수면온도와 주변 육지 기온의 차이가 커질수록 강도가 강해진다. 오호츠크해고기압의 첫 출현일이 일러짐에 따라 4월과 5월의 오호츠크해고기압 출현일수는 증가하고 강도는 약해질 수 있다. 그러나 6월에는 반대의 경향이 나타날 수 있다.

• ALGAE
• /
• 제25권2호
• /
• pp.77-87
• /
• 2010

Eight unusual individuals of a laminariaceaen species were collected from the Sea of Okhotsk in 1974 and described as a new species, Laminaria multiplicata Petrov et Suchovejeva in 1976. Since that time no new information, including pictures and numerical data, has been provided, although the species was cited in floristic lists of the Sea of Okhotsk based on the first record in 1976. We investigated a type and 3 paratypes of L. multiplicata and strongly believe that they were wrongfully identified abnormal plants of L. gurjanovae A. Zinova. Therefore, the species L. multiplicata needs to be closed.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
• /
• pp.76-82
• /
• 1998

Increase of greenhouse gas due to $CO_2$ and CH$_4$ gases would cause the global warming in the atmosphere. According to the global circulation model, it is pointed out in the Okhotsk Sea that the large increase of atmospheric temperature might be occurredin this region by global warming due to the doubling of greenhouse effectgases. Therefore, it is very important to monitor the sea ice extents in the Okhotsk Sea. To improve the sea ice extents and concentration with more highly accuracy, the field experiments have begun to comparewith Airborne Microwave Radiometer (AMR) and video images installed on the aircraft (Beach-200). The sea ice concentration is generally proportional to the brightness temperature and accurate retrieval of sea ice concentration from the brightness temperature is important because of the sensitivity of multi-channel data with the amount of open water in the sea ice pack. During the field experiments of airborned AMR the multi-frequency data suggest that the sea ice concentration is slightly dependending on the sea ice types since the brightness temperature is different between the thin and small piece of sea ice floes, and a large ice flow with different surface signatures. On the basis of classification of two sea ice types, it is cleary distinguished between the thin ice and the large ice floe in the scatter plot of 36.5 and 89.0GHz, but it does not become to make clear of the scatter plot of 18.7 and 36.5GHz Two algorithms that have been used for deriving sea ice concentrations from airbomed multi-channel data are compared. One is the NASA Team Algorithm and the other is the Bootstrap Algorithm. Intrercomparison on both algorithms with the airborned data and sea ice concentration derived from video images bas shown that the Bootstrap Algorithm is more consistent with the binary maps of video images.

• 지구물리
• /
• 제7권3호
• /
• pp.207-215
• /
• 2004

오호츠크해는 동해와 연결된 바다로 세계에서 가장 유망한 가스하이드레이트 부존지역 중 하나이다 오호츠크해의 가스하이드레이트 퇴적층의 지구물리 구조를 규명하기 위해 2003년 8월과 10월 두차례에 걸처 사할린 북동 대륙사면지역에서 오호츠크해 가스하이드레이트 국제공동연구(CHAOS) 탐사가 수행되었다. 이번 탐사에서는 고해상도 천부지층 탄성파 수중음향(hydroacoustic) 자료 등을 획득하였다. 스파커 음원을 이용하여 얻은 탄성파 단면도에는 가스하이드레이트 BSR이 뚜렷하지 않지만 BSR 깊이 부근에 분산적으로 나타나는 진폭이 강화된 반사층들이 관찰되었다. 따라서 사용하는 음원의 주파수에 따라 BSR의 반사특성이 다르게 나타남을 알 수 있다. 또한 BSR깊이에서 해저면으로 상승한 좁은 폭의 가스기둥 (gas chimney)들이 다수 발견되었다. 이 기둥들은 내부음향특성이 전혀 보이지 않는 (wipe-out : WO)그룹과 주변에 비해 상대적으로 강한 반사특성(enhanced reflection; ER)을 보이는 그룹으로 나누어진다. 이런 반사특성 차이는 기둥내에 가스 또는 가스하이드레이트 중 어떤 물질이 집중적으로 충적되었는지에 따라 구별되는 현상으로 해석된다. 수중음향자료에는 지층으로부터 해수중으로 수백 의 높이까지 뿜어져 오르는 많은 가스분출기둥들이 관찰되었다. 가스분출기둥들은 가스하이드레이트 안정영역에 해당하는 상대적으로 깊은 수심에서 관찰된다. 이는 지층의 가스기둥 주변을 둘러싼 가스하이드레이트 퇴적층이 가스가 스며들지 못하는 차단벽을 형성하면서 심부에서 공급되는 가스의 대부분이 가스기둥을 따라 해저면까지 운반되며 이에 따라 가스기둥 위의 표층에서 해수중으로 분출하는 가스분출기둥이 형성된다.