• 한국수산과학회지
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• 제56권4호
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• pp.449-461
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• 2023

The aim of this study was to conduct an ecosystem-based fishery risk assessment of tuna fisheries in the Western Indian Ocean. We selected gillnet, purse seine, hand line, baitboat, and longline fisheries as the target fisheries method, and selected longtail tuna (Thunnus tonggol), narrow-barred Spanish mackerel (Scomberomorus commerson), kawakawa (Euthynnus affinis), skipjack tuna (Katsuwonus pelamis), yellowfin tuna (T. albacares), bigeye tuna (T. obesus), albacore tuna (T. alalunga) and swordfish (Xiphias gladius) as the target species. The risk score for the size at the first capture in sustainability objective was high, especially, for the purse seine and baitboat fisheries using the fish aggregating devices (FADs). The risk score for the bycatch in the biodiversity objective was high for the gillnet fishery, and the gillnet fisheries using FADs showed high risks for the habitat quality objective due to the loss of the fishing gears. With regards to the socio-economic benefits objective, the risk score of the sales profits was low due to high sales of the tuna fisheries. The ecosystem risk score in the Western Indian Ocean was estimated to be moderate, although management is required for some of the indicators that have high-risk scores.

• Asian review of World Histories
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• 제3권1호
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• pp.37-58
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• 2015

The paper examines, in the light of current historiography, the recent trends in the application and applicability of the World Historical studies on the Indian Ocean scenario. Calling for the combination of the breadth of the World Historical studies with the analysis of a historical scenario in its specific spatio-temporal context-instead of a synchronic approach-the present study takes a close look at commerce and politics in the western Indian Ocean in the light of an early 14th century Latin Crusade tract, How to Defeat the Saracens by William of Adam (Guillelmus Ade, Tractatus quomodo Sarraceni sunt expugnandi), a Dominican friar. The text offers remarkable insights into the interlocking of the Indian Ocean and the South Asian subcontinent with the Mamluk Sultanate, the Ilkhanid realm and the Crusades. The paper argues for what is now termed as braided and connected histories.

• Ocean and Polar Research
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• 제35권3호
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• pp.259-272
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• 2013

One of the factors influencing the climate around Korea is the oceanic-atmospheric variability in the tropical region between the eastern Indian and the western Pacific Oceans. Lack of knowledge about the air-sea interaction in the tropical Indo-Pacific region continues to make it problematic forecasting the ocean climate in the East Asia. The 'Tropical Indo-Pacific water transport and ecosystem monitoring EXperiment (TIPEX)' is a program for monitoring the ocean circulation variability between Pacific and Indian Oceans and for improving the accuracy of future climate forecasting. The main goal of the TIPEX program is to quantify the climate and ocean circulation change between the Indian and the Pacific Oceans. The contents of the program are 1) to observe the mixing process of different water masses and water transport in the eastern Indian and the western Pacific, 2) to understand the large-scale oceanic-climatic variation including El Nino-Southern Oscillation (ENSO)/Warm Pool/Pacific Decadal Oscillation (PDO)/Indian Ocean Dipole (IOD), and 3) to monitor the biogeochemical processes, material flux, and biological changes due to the climate change. In order to effectively carry out the monitoring program, close international cooperation and the proper co-work sharing of tasks between China, Japan, Indonesia, and India as well as USA is required.

• Asian review of World Histories
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• 제4권2호
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• pp.191-205
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• 2016

The Periplus of the Erythraean Sea is a Roman period guide to trade and navigation in the Indian Ocean. Justly famous for offering a contemporary and descriptive account of early Indian Ocean trade, the work has been subject to and a point of departure for numerous studies. Its extensive influence on scholarship is, however, also problematic, as it reflects the limited information and cultural and personal bias of its unknown author. Arguably this might have led scholars to overemphasise so-called western or Roman participation in early Indian Ocean trade. Network analysis allows us to map, visualize and measure interconnectedness in the Periplus Maris Erythraei. Many of these connections are not explicitly mentioned in the text, but by connecting not only places with places, but also products with places that export and import them, we get a partly different impression of Indian Ocean trade from that conventionally gathered from the Periplus. It allows us to ask questions about the relationship between coastal cabotage and transoceanic shipping, to identify regional trading circuits, and unexpected centres of long-distance exchange.

• 한국수산과학회지
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• 제51권3호
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• pp.286-297
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• 2018

We analyzed scientific observer data to identify species composition and catch trends of Korean tuna longline fisheries in the Indian Ocean. The data were collected by Korean scientific observers onboard Korean tuna longline fishing vessels in the Indian Ocean from 2010 to 2015. The observers identified 94 species including 5 tuna, 6 billfish, 11 shark, 7 other fish, 5 seabird and 1 sea turtle. Albacore tuna Thunnus alalunga and southern bluefin tuna Thunnus maccoyii were the dominant tuna species, and swordfish Xiphias gladius were the most commonly captured billfish. During the survey periods, 87 seabirds were incidentally bycaught. Black-browed albatross Diomedea melanophris was the dominant seabird species in bycatch, especially in 2010. Cluster analysis showed difference in the species composition of catches between the eastern and western Indian Ocean.

• 대기
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• 제25권1호
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• pp.179-183
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• 2015

Even though state-of-the-art general circulation models is improved step by step, the seasonal predictability of the East Asian summer monsoon still remains poor. In contrast, the seasonal predictability of western North Pacific and Indian monsoon region using dynamic models is relatively high. This study builds canonical correlation analysis model for seasonal prediction using wind fields over western North Pacific and Indian Ocean from the Global Seasonal Forecasting System version 5 (GloSea5), and then assesses the predictability of so-called hybrid model. In addition, we suggest improvement method for forecast skill by introducing the lagged ensemble technique.

• 한국농림기상학회지
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• 제7권4호
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• pp.240-249
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• 2005

일반적으로 인도양 동쪽 해수면 온도는 따뜻하고, 서쪽 해수면 온도는 차갑다. 이러한 인도양 동/서쪽의 해수면 온도 변화는 인도 해양 다이폴 현상(Indian Ocean Dipole Mode, IODM)이 그 원인이다. 다이폴의 양의 위상은 서쪽 인도양에 양의 SST 아노말 리가 나타나고, 남동 인도양에는 음의 SST 아노말리가 나타나고 음의 위상은 이와 반대의 SST 아노말리가 나타난다. 반면 태평양의 경우, 일반적으로 서쪽 해수면 온도는 따뜻하고, 동쪽 해수면 온도는 차갑다. 중앙/동(서) 태평양 해양의 양(음)의 SST 아노말리가 현상이 나타날 때는 엘니뇨 시기이다. 이와 반대의 SST 아노말리 현상은 라니냐 시기이다 이러한 태평양의 대기-해양간의 상호작용으로 나타나는 현상을 엘니뇨 난방진동(El Nino Southern Oscillation, ENSO)이라 한다. 본 연구에서는 IODM과 ENSO현상에 따른 동아시아 몬순 변동성을 분석하기 위해 관측자료와 NCAR MCA모델 자료를 사용하였다 IODM과 ENSO 현상과 관련된 SST 아노말리 5가지 실험을 수행하였다. IDO모드는 최고의 값이 나타난 이후 약 $3\~4$계절의 시간 지연을 가지고 동아시아의 여름 몬순 활동에 영향을 주는 반면, ENSO는 동아시아 여름 몬순과 같은 계절에 영향을 준다. IODM 음(양의)위상과 태평양에서의 엘니뇨(라니냐) 현상은 한국과 일본지역에서 몬순 활동을 강화(억제)하는 역할을 한다. 반면 중국 지역에서는 IDOM과 몬순 변동성과는 별다른 연관성이 없는 것으로 나타났다. 그러나 엘니뇨(라니냐)일 때, 중국 지역에서 몬순 활동은 억제(강화)되는 경향을 보였다. IODM은 북태평양 아열대 고기압이 강화 할 때 나타나고, ENSO는 북서 태평양 알류산 저기압의 영향으로 나타난다. 따라서 태평양으로부터 동아시아 쪽으로의 수분 공급은 아열대 고기압과 알류산 저기압의 강화/약화에 의해 결정된다.

• 한국지구과학회지
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• 제28권1호
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• pp.35-44
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• 2007

본 연구에서는 엘니뇨현상과 인도양 쌍극자 모드(Indian Ocean Dipole, IOD) 현상의 상호 관련성과, 우리나라 기온, 강수량에 대한 두 현상의 영향을 분석하였다. 1954년부터 2004년까지 51년간 NINO 3 지수, IOD지수, 그리고 전국 11개 지점 지역평균한 월별 평균기온과 강수량 자료를 사용하였다. 엘니뇨현상과 IOD현상은 봄과 가을에는 동시 상관관계가 존재한다. 인도양에서 해수면온도 분포는 엘니뇨 해에는 남북진동이, IOD 해에는 동서진동 형태가 뚜렷하였다. 엘니뇨 해 우리나라에서는, 여름철에 냉하다우, 겨울철에 온난다우 경향이 뚜렷한 반면에, IOD 해에는 유의한 상관성을 찾을 수 없었다. 대기대순환에서도 엘니뇨 해에는 우리나라를 포함한 중위도에 통계적으로 신뢰할 만한 편차패턴이 나타나지만, IOD 해에는 그렇지 않았다.

• 한국동물생명공학회지
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• 제39권1호
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• pp.31-39
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• 2024

Background: The biological information of fish, which include reproduction, is the prerequisite and the basis for the assessment of fisheries. Methods: The aim of this work was to know the reproductive biology with the first sexual maturity (TL₅₀) and the spawning period for 58 mainly fish species in the waters around La Réunion Island (Western Indian Ocean). Twenty families belonging to the Actinopterygii were represented (acanthuridae, berycidae, bramidae, carangidae, cirrhitidae, gempylidae, holocentridae, kyphosidae, labridae, lethrinidae, lutjanidae, malacanthidae, monacanthidae, mullidae, polymixiidae, pomacentridae, scaridae, scorpaenidae, serranidae, sparidae; 56 species; n = 9,751) and two families belonging to the Elasmobranchii (squalidae, centrophoridae; 2 species; n = 781) were sampled. Between 2014 and 2022, 10,532 individuals were sampled covering the maximum months number to follow the reproduction periods of these species. Results: TL₅₀ for the males and the females, respectively, ranged from 103.9 cm (Acanthurus triostegus) to 1,119.3 cm (Thyrsitoides marleyi) and from 111.7 cm (A. triostegus) to 613.1 cm (Centrophorus moluccensis). The reproduction period could be very different between the species from the very tight peak to a large peak covered all months. Conclusions: Most species breed between October and March but it was not the trend for all species around La Réunion Island.

• 한국항해항만학회지
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• 제26권3호
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• pp.345-354
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• 2002

8-9세기는 무슬림 상인의 주도로 페르시아만에서 남중국까지의 해로가 활성화되는 시기이다. 동서교류에서 해로가 육로를 능가하는 이 시기에는, 이 간선 해로를 따라 그 동단인 동아시아해역과 그 서단인 지중해 해역이 설정되었다. 먼저 간선 해로에 관해, 기존 연구에서 미진하게 검토한 페르시아만에서 인도 동쪽 바다까지의 왕복 항로와 아랍선박을 검토하였으며 심해항행이 진행되었다는 것을 지적하였다. 다음으로 이 시기에 동아시아해역의 해상무역이 장보고의 활약으로 활성화되었던 것과는 달리, 지중해 해역은 로마제국 시대의 활기를 잃고 상대적으로 위축되어 있다는 것을 지적하였다.