• Title/Summary/Keyword: oceanic climate

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Climate Change and the Thermohaline Circulation of the Oceans (기후 변환와 해양 열염분 순환)

  • Park, Young-Gyu
    • Atmosphere
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    • v.15 no.1
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    • pp.69-74
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    • 2005
  • In this short article, oceanic processes that could have strong effect on the climate have been explained while focusing on the oceanic thermohaline circulation (THC). First, the structure of THC is explained using a simple scaling law. Then, the thermohaline catastrophe, which is believed to be a cause of a rapid climate changes observed in paleoclimate records, and interdecadal variations in THC are explained. The interactions between the oceans and $CO_2$ are also mentioned briefly.

Consideration of Time Lag of Sea Surface Temperature due to Extreme Cold Wave - West Sea, South Sea - (한파에 따른 표층수온의 지연시간 고찰 - 서해, 남해 -)

  • Kim, Ju-Yeon;Park, Myung-Hee;Lee, Joon-Soo;Ahn, Ji-Suk;Han, In-Seong;Kwon, Mi-Ok;Song, Ji-Yeong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.6
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    • pp.701-707
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    • 2021
  • In this study, we examined the sea surface temperature (SST), air temperature (AT), and their time lag in response to an extreme cold wave in 2018 and a weak cold wave in 2019, cross-correlating these to the northern wind direction frequency. The data used in this study include SST observations of seven ocean buoys Real-time Information System for Aquaculture Environment provided by the National Institute of Fisheries Science and automatic weather station AT near them recorded every hour; null data was interpolated. A finite impulse response filter was used to identify the appropriate data period. In the extreme cold wave in 2018, the seven locations indicated low SST caused by moving cold air through the northern wind direction. A warm cold wave in 2019, the locations showed that the AT data was similar to the normal AT data, but the SST data did not change notably. During the extreme cold wave of 2018, data showed a high correlation coefficient of about 0.7 and a time lag of about 14 hours between AT and SST; during the weak cold wave of 2019, the correlation coefficient was 0.44-0.67 and time lag about 20 hours between AT and SST. This research will contribute to rapid response to such climate phenomena while minimizing aquaculture damage.

Tracking the Movement and Distribution of Green Tides on the Yellow Sea in 2015 Based on GOCI and Landsat Images

  • Min, Seung-Hwan;Oh, Hyun-Ju;Hwang, Jae-Dong;Suh, Young-Sang;Park, Mi-Ok;Shin, Ji-Sun;Kim, Wonkook
    • Korean Journal of Remote Sensing
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    • v.33 no.1
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    • pp.97-109
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    • 2017
  • Green tides that developed along the coast of China in 2015 were detected and tracked using vegetation indices from GOCI and Landsat images. Green tides first appeared near the Jiangsu Province on May 14 before increasing in size and number and moving northward to the Shandong Peninsula in mid-June. Typhoon Cham-hom passed through the Yellow Sea on July 12, significantly decreasing the algal population. An algae patch moved east toward Korea and on June 18 and July 4, several masses were found between the southwestern shores of Korea and Jeju Island. The floating masses found in Korean waters were concentrated at the boundary of the open sea and the Jindo cold pool, a phenomenon also observed at the boundary of coastal and offshore waters in China. Sea surface temperatures, derived from NOAA SST data, were found to play a role in generation of the green tides.

A Study for Improving the KORDI Buoy System in Comparison with TRITON Buoys in the Tropical Pacific Ocean (열대 태평양에서 운영되는 TRITON 부이와 비교를 통한 KORDI 부이 시스템 개선 연구)

  • Kim, Dong-Guk;Jeon, Dong-Chull;Kim, Eung;Hwang, Keun-Choon;Hwang, Sang-Chul
    • Ocean and Polar Research
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    • v.33 no.spc3
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    • pp.359-369
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    • 2011
  • This study documents KORDI's experience of successfully deploying a deep ocean buoy for monitoring oceanic and atmospheric variabilities in the tropical western Pacific Ocea nsince May 2010. The primary focus of this study was to compare TRITON (big and old type) with m-TRITON (smaller and new type) buoys within the JAMSTEC's buoy management system. The objective of operating a KORDI buoy is to ascertain oceanic variability in the tropical western Pacific. We adopted a slack-line mooring type to observe water temperatures at six layers from surface to 400 m depth. However, we could not acquire satisfactory results due to lack of expertise in buoy management system. A new KORDI buoy has been developing, which has been modified from both buoys, and ARGOS-3 satellite system and a slack-type mooring line.

On Climatic Characteristics in the East Asian Seas by satellite data(NOAA, Topex/Poseidon) (위성자료(NOAA, Topex/Poseidon)를 이용한 한반도 주변해역의 기후적 특성)

  • 윤홍주
    • Journal of Environmental Science International
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    • v.10 no.6
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    • pp.423-429
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    • 2001
  • Satellite data, with sea surface temperature(557) by NOAA and sea level(SL) by Topex/poseidon, are used to estimate characteristics on the variations and correlations of 557 and SL in the East Asian Seas from January 1993 through May 1998. We found that there are two climatic characteristics in the East Asian seas the oceanic climate, the eastern sea of Japan, and the continental climate, the eastern sea of China, respectively. In the oceanic climate, the variations of SL have the high values in the main current of Kuroshio and the variations of 557 have not the remarkable seasonal variations because of the continuos compensation of warm current by Kuroshio. In the continental climate, SL has high variations in the estuaries(the Yellow River, the Yangtze River) with the mixing the fresh water and the saline water in the coasts of continent and 557 has highly the seasonal variations due to the climatic effect of continents. In the steric variations of summer, the eastern sea of Japan, the East China Sea and the western sod of Korea is increased the sea level about 10~20cm. But the Bohai bay in China have relatively the high values about 20~30cm due to the continental climate. generally the trends of SST and SL increased during all periods. That is say, the slopes of 557 and SL Is presented 0.29$^{\circ}C$/year and 0.84cm/year, respectively. The annual and semi-annual amplitudes have a remarkable variations in the western sea of Korea and the eastern sea of Japan. In the case of the annual peaks, there appeared mainly In the western sea of Korea and the eastern sea of .Japan because of the remarkable variations of SL associated with Kuroshio. But in the case of the semi-annual peaks, there appeared in the eastern sea of Japan by the influence of current, and in the western sea of Korea by the influence of seasonal temperature, respectively. From our results, it should be believed that 557 and SL gradually Increase in the East Asian seas concerning to the global warming. So that, it should be requested In the international co-operation against In the change of the abnormal climate.

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Distribution of Fish Larvae in the Southern Coastal Waters (Yeosu, Namhae and Tongyoung) of Korea in Spring and Summer (한국 남해안(여수, 남해, 통영) 연안해역 춘·하계 어류 자치어 분포 특성)

  • Choi, Hee Chan;Yoo, Man Ho;Youn, Seok Hyun;Oh, Hyun Ju
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.23 no.6
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    • pp.759-766
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    • 2017
  • In order to identify the species composition and distribution pattern of larval fish assemblages in the southern coastal waters of Korea, monthly samples were taken using an RN80 net which was towed horizontally in three different regions (Yeosu, Namhae and Tongyoung) between May to September 2016. A total of fifty taxa were collected during the study. Among these, Engraulis japonicus, which accounted for 56.8 % of the total population, was the most dominant species, followed by Sillago japonicus, Parablennius yatabei, Gobiidae Type A, Parablennidae sp., and Omobranchus elegans as dominant taxa, that accounted for 87.5% of the total number of individuals. ANOSIM results revealed that regional groups were not separated, but seasonal groups were clearly divided with statistical significance, and these differences were caused mainly by water temperature variations identified by canonical analysis.

Effects on Vegetation Distribution of Odaesan National Park according to Climate and Topography of Baekdudaegan, Korea

  • Han, Bong-Ho;Choi, Jin-Woo;Yeum, Jung-Hun
    • Journal of Environmental Science International
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    • v.26 no.10
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    • pp.1111-1124
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    • 2017
  • This study aimed to understand the distribution of vegetation in the eastern and western sides of the Baekdudaegan (ridge) dividing the Odaesan National Park, as influenced by its topography and climate. The actual vegetation, topography and climate for each side were used in the overlay analysis. The results of the analysis of actual vegetation showed a high distribution rate of Quercus mongolica forest on both the eastern and western sides. On the eastern side, the distribution rate of Pinus densiflora forest and P. densiflora-Q. variabilis forest was high, while the western side had a high distribution rate of deciduous broad-leaved tree forest and Abies hollophylla forest. A clear trend was identified for vegetation distribution with respect to elevation but not with respect to slope or aspect. The results of micro-landform analysis showed that the P. densiflora forests in the ridge and slope and the deciduous broad-leaved tree forest in the valley were respectively distributed with a high ratio. In terms of climate, the eastern side revealed an oceanic climate, with a relatively high average annual temperature, while the western side was characterized by relatively high average annual humidity and average annual precipitation. The distribution rate of P. densiflora forest was found to be high on the eastern side of the mountain range.

The Characteristics of Spatio-Temporal Distribution on Phytoplankton in the Nakdong River Estuary, during 2013-2015 (낙동강 하구역에서 2013-2015년 식물플랑크톤의 시·공간분포 특성)

  • Yoo, Man-Ho;Youn, Seok-Hyun;Park, Kyung-Woo;Kim, A-Ram;Yoon, Sang-Chol;Suh, Young-Sang
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.22 no.6
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    • pp.738-749
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    • 2016
  • To understand the characteristics of the spatio-temporal distribution of phytoplankton after barrage construction in the Nakdong River Estuary, this study investigated relevant environmental parameters and phytoplankton status based on bi-monthly samples collected from the Nakdong River Estuary itself from February 2013 to December 2015. Environmental parameters did not differ significantly across these years but did vary between zones and seasons. The results suggested that the upper zone was dominated by fresh-water diatoms, green algae, and blue-green algae, whereas the lower zone was mostly dominated by dinoflagellates. The presence of Stephanodiscus spp., Asterionellopsis formosa, and Microcystis spp. in the upper zone was related to the inflow of freshwater discharge by artificial control of dyke gates. The dominant phytoplankton species in this zone were dependent on temperature, wind speed, DIP, and DIN, while those in the lower zone were mostly dependent on nutrients and wind speed. In addition, at the lower zone, there were negative correlations between Prorocentrum donghaiense, DIN, and wind speed, with its abundance being higher during the summer than other seasons. Analysis of temporal variations did not indicate any significant differences in the upper zone but did reveal variations among seasons at the lower zone. Except in 2014, the lower zone could be divided into periods dominated by diatoms (October-April) and dinoflagellates (June-August). These results suggest that the characteristics of the phytoplankton community were influenced by changes in the inflow of freshwater species and nutrients given the difference in the range affected by freshwater discharge.

TIPEX (Tropical Indo-Pacific water transport and ecosystem monitoring EXperiment) Program (태평양-인도양 해양순환 연구 프로그램)

  • Jeon, Dongchull;Kim, Eung;Shin, Chang Woong;Kim, Cheol-Ho;Kug, Jong Seong;Lee, Jae Hak;Lee, Youn-Ho;Kim, Suk Hyun
    • Ocean and Polar Research
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    • v.35 no.3
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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.

On Climatic Characteristics in the East Asian Seas by satellite data(NOAA, Topex/Poseidon) (위성자료(NOAA, Topex/Poseidon)를 이용한 한반도 주변해역의 기후적 특성 연구)

  • 윤홍주;김상우;이문옥;박일흠
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2001.10a
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    • pp.290-294
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    • 2001
  • Satellite data, with Sea Surface Temperature(SST) by NOAA and Sea Level(SL) by Topex/poseidon, are used to estimate characteristics on the variations and correlations of SST and SL in the East Asian Seas from January 1993 through May 1998. In the oceanic climate, the variations of SL shown the high values in the main current of Kuroshio and the variations of SST shown not the remarkable seasonal variations because of the continuos compensation of warm current by Kuroshio. In the continental climate, SL shown high variations in the estuaries(the Yellow River, the Yangtze River) with the mixing the fresh water in the mouth of estuaries of the saline water in the coasts of continent and SST shown highly the seasonal variations due to the climatic effect of continents. In the steric variations in summer, the eastern sea of Japan, the East China Sea and the western sea of Korea shown the increment of sea level with 10~20cm. But the Bohai bay in China shown relatively the high values of 20~30cm due to the continental climate. Generally the trends of SST and SL increased during all periods. That is say, the slopes of SST and SL presented 0.29$^{\circ}C$/year and 0.84cm/year, respectively. The annual and semi-annual amplitudes shown a remarkable variations in the western sea of Korea and the eastern sea of Japan.

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