• Ocean and Polar Research
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• 제25권4호
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• pp.503-518
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• 2003

This study examines the relationship among temperature, wind, and sea level pressure to understand recent warming in the vicinity of the Antarctic Peninsula. To do this, the surface air temperature, NCEP/NCAR reanalysis wind data and sea level pressure data for the period of 40 years are analyzed. The 40-year surface air temperature data in the Antarctic Peninsula reveals relatively the larger warming trends for autumn and winter than other seasons. The variability of the surface air temperature in this region is compared with that of the regional atmospheric circulation. The surface air temperature is positively correlated with frequency of northwesterlies and negatively correlated with frequency of southeasterlies. This relation is more evident in the northern tip of the Antarctic Peninsula for autumn and winter. The trend analysis of wind frequency in the study area shows increasing and decreasing trends in the frequency of northwesterlies and southeasterlies, respectively, in the northwestern part of the Weddell Sea for autumn and winter. And also it is found that these winds are closely related with decreasing of sea level pressure in the southeastern region of the Antarctic Peninsula. Furthermore from the seasonal variation of sea level pressure in this area, it may be presumed that decreasing of sea level pressure in the southeastern region of the Antarctic Peninsula is related with warming in the vicinity of the Antarctic Peninsula for autumn and winter. Therefore it can be explained that recent warming in the vicinity of the Antarctic Peninsula is caused by positive feedback mechanism, that is, the process that warming in the vicinity of the Antarctic Peninsula can lead to the decrease of sea level pressure in the southeastern region of the Antarctic Peninsula and these pressure decrease in turn lead to the variation of wind direction in northwestern part of Weddell Sea, again the variation of wind direction enhances the warming in the Antarctic Peninsula.

• Ocean and Polar Research
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• 제24권3호
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• pp.267-278
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• 2002

This study investigated the spatial characteristics of warming trends and the dipole-like pattern of temperature field in the Antarctic Peninsula using surface air temperature (SAT) of 10 stations in the vicinity of the Antarctic Peninsula. SAT data for the 1962-2001 period at 6 stations (Rothera, Faraday/Vernadsky, Bellingshausen, Orcadas, Esperanza, Halley) revealed in general the larger warming trends in autumn and winter except for Halley. The largest warming was shown for August in the west side of the Peninsula (more than $0.9^{\circ}C/decade$). On the other hand, the recent 14-year SAT data showed the strong warming trends at 9 stations except for Halley in the earlier period (April-June) than August for the 1962-2001 period. The largest warming appeared in May at Esperanza and Butler Island. SAT of the two sides showed significant positive correlations over most of the period except for the mid- and the late 1970s, in which significant negative correlations were found. In the correlation analysis between SAT and sea surface temperature (SST) anomalies in the NINO 3.4 region, strong negative correlation was found in the west side of the Peninsula. Details of the correlation analysis exhibited that the negative correlation was significantly strong from the early 1980s to the mid-1990s. However, it was difficult to find significant correlations of ENSO with SAT in the east side of the Peninsula. So, in this study it failed to find out clearly the out-of-phase relationship of SAT across the Antarctic Peninsula.

• Ocean and Polar Research
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• 제23권4호
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• pp.425-431
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• 2001

From an ecological point of view, the western part of the Atlantic sector is one of the most productive areas in the Southern Ocean. Antarctic krill (Euphausia superba) and krill-dependent predators such as fish, seals, and birds are abundant there, and most krill fisheries have operated in this area since 1970s. The hottest issues for the proper management of krill resources nowadays are to determine total biomass in this area, and to identify environmental forces controlling stock fluctuation. This paper reviews and collates information on ongoing oceanographic activities in the Antarctic Peninsula region concerning these issues. To delineate the status and function of Antarctic krill population in Antarctic marine ecosystems, multinational researches along the Antarctic Peninsula area have been developing recently. Four member states of CCAMLR (Japan, Russia, UK, and USA) had conducted acoustic surveys in January-February 2000 (socalled CCAMLR-2000 survey), and krill standing stock at 120 kHz was estimated to be 44.29 million metric tonnes in the western Atlantic sector of the Southern Ocean. On the other hand, the Southern Ocean GLOBEC (SO-GLOBEC) Programme has prepared a serial winter survey to examine the factors that govern krill survivorship and distribution in relation to shelf circulation processes. Ship-based surveys using ice-breakers are being conducted by three nations (Germany, UK, and USA) around the Marguerite Bay during the austral fall and winter 2001 and 2002. In addition to these two large-scale surveys, some CCAMLR members have carried out joint oceanographic surveys near the South Shetland Islands to detect ecosystem changes since 1994. Especially from December 1999 to February 2000, in conjunction with CCAMLR-2000 survey, four nations (Japan, Korea, Peru, and USA) conducted acoustic surveys to produce time-series information on krill distribution and biomass near the South Shetland areas. Though the aims of each program and the approach to solve the scientific questions were different each other, the results from each program fill the gaps between programs. Further cooperation and exchange in these activities could be beneficial to each program.

• Ocean and Polar Research
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• 제26권3호
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• pp.453-463
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• 2004

The Antarctic Peninsula is important in terms of global warming research due to pronounced increase of air temperature over the last century. The first eddy covariance system was established at King Sejong Station located in the northern region of the Antarctic Peninsula in December of 2002 and has been operated over one year. Here, we analyze turbulent characteristics to determine quality control criteria for turbulent sensible heat flux data as well as to diagnose the possibility of long term eddy covariance measurement under extreme weather conditions of the Antarctic Peninsula. We also report the preliminary result on sensible heat flux. Based on the analyses on turbulent characteristics such as integral turbulence characteristics of vertical velocity (w) and heat (T), stationarity test and investigation of correlation coefficient, they fallow the Monin-Obukhov similarity and eddy covariance flux data were reliable. ${\sim}47%$ of total retrieved sensible heat flux data could be used for further analysis. Daytime averaged sensible heat flux showed a pronounced seasonal variation, with a maximum of up to $300Wm^{-2}$ in summer. In conclusion, continuous and long-term eddy covariance measurement may be possible at the study site and the land surface may influence the atmosphere significantly through heat transport in summer.

• Ocean and Polar Research
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• 제24권3호
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• pp.301-311
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• 2002

We used diatom and porewater data of two piston cores from the central subbasin and one from the western subbasin in the Bransfield Strait in the northern Antarctic Peninsula to elucidate the depositional mechanism of the layered diatom ooze. The layered diatom ooze is characterized by an abundance of organic carbon, biogenic silica, sulfde sulfur, and lower porewater sulfate concentration. This lack of pore-water sulfate concentration in the diatom ooze interval may reflect development of reducing micro-environment in which bacterially mediated sulfate reduction occurred. The negative relationship between the total organic carbon and sulfate contents, however, indicates that sulfate reduction was partly taking place but does not control organic carbon preservation in this unit. Rather, well-preserved Chaetoceros resting spores in the layered diatom ooze indicate a rapid sedimentation of the diatom as a result of repetitive iceedge blooms on the Bransfield shelf during the cold period (around 2500 yrs BP) when the permanent seaice existed on the shelf, During this period, it is expected that the downslope-flowing cold and dense water was also formed on the Bransfield shelf as a result of sea ice formation, playing an important role for the formation of layered diatom ooze in the Bransfield subbasins.

• Journal of Korean Society for Atmospheric Environment
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• 제16권E2호
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• pp.85-96
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• 2000

The concentrations of Pb, Mn, Al and Na were measured from a total of 26 snow samples collected from a 1.5-m deep snow pit in Livingston Island, South Shetland Islands, at the northern tip of the Antarctic Peninsula. Ore sampling location is great concern, because of its proximity to the southern extremity of south America, a candidate for the source regions of pollutant aerosols entering Antarctica. The mean concentrations of Pb and Mn were found to be 4.97 pg g(sup)-1 and 20.6 pgg(sup)-1, respectively. These concentrations levels are similar to those reported for recent snow at other Antarctic sites with pronounced spring maxima for both metals. Contributions form natural sources are estimated to be minor (∼16%) for Pb. For Mn, on the other hand, contribution from rock and soil dusts is found to be very important. Excess Pb over Pb from natural sources is likely to be anthropogenic, especially from South Americal. Our results show that yearly Pb fallout flux is much greater in Antarctic coastal areas than at other Antarctic locations far from the coast , indicating that the transport and deposition patterns of pollutant aerosols are not simple is Antarctica. It is also suggested that the recycling of anthropogenic Pb in seawater to the atmosphere could significantly contribute to the Pb fallout flux in the Antarctic coastal regions.

• Journal of Microbiology
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• 제44권5호
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• pp.480-491
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• 2006

As part of the long-term monitoring projects on Antarctic terrestrial vegetation in relation to global climate change, a lichen floristical survey was conducted around the Korean Antarctic Station (King Sejong Station), which is located on Barton Peninsula, King George Island, in January and February of 2006. Two hundred and twenty-five lichen specimens were collected and sixty-two lichen species in 38 genera were identified by morphological characteristics, chemical constituents, TLC analysis and ITS nucleotide sequence analysis.

• 지구물리
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• 제3권3호
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• pp.141-152
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• 2000

남극반도 엘리펀트섬 북부의 남극-스코시아판 경계부에서 획득한 지구물리 자료(탄성파, 중력자료)는 셰클턴 파쇄대를 따라 지각구조의 급격한 변화를 보여준다. 이들 자료에 의하면 셰클턴 파쇄대의 해저산맥은 남극반도 대륙주변부 앞에서 중단되지만, 파쇄대의 변환단층대는 엘리펀트섬 부근의 주변부까지 계속 연장되며 그 넓이도 확장되고 있음을 보여준다. 즉 셰클턴 파쇄대의 변환단층은 남동쪽으로 내려오면서 (1) 드레이크 해협에서는 지구(graben) 구조의 함몰대, (2) 파쇄대 산맥의 남쪽 끝, 삼중점 바로 남동쪽에서는 해양지각에 대규모 반지구(half-graben) 구조, (3) 남극반도 엘리펀트섬 북쪽 대륙사면을 심하게 변형시키는 단층군으로 그 형태를 변화한다. 셰클턴 파쇄대의 단층대를 따라 두 단계의 판구조 환경 변화가 진행되었다. 첫 번째 단계는 대규모 정단층운동에 의해 반지구구조와 같은 확장구조를 형성시킨 확장력 환경이다. 이 시기는 드레이크 해협의 확장이 진행되었던 중기 마이오신세(약 $10Ma{\sim}20Ma$ 사이)에 해당된 것으로 추정된다. 두 번째 단계는 셰클턴 단층을 역단층운동으로 재활성화 시킨 최근의 압축력 환경으로, 이는 최근 약 6Ma이후 진행된 스코시아판의 서향운동으로 인한 남극판과의 수렴작용에 의한 것이다.

• Journal of Ecology and Environment
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• 제40권1호
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• pp.55-65
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• 2016

Background: In this article, it was analyzed how snow melting affects the assembly of lichen and moss communities in a small area of the coastal region of Barton Peninsula, which is in maritime Antarctic. In the small area, even though there is a huge gap of difference of the environment between the snow-filled area and snow-melt one, the latter did not have distinctive environmental gradients. Results: Depending on the snow melting time, coverage and species diversity of lichens and mosses tend to increase remarkably. For species with significant changes depending on the snow-covered period, there are Andreaea regularis, crustose lichens, Placopsis contortuplicata, Usnea aurantiaco-atra, and snow algae. In this area, the process of vegetation assembly process has shown the directional development in the order of snow algae${\rightarrow}$crustose, lichen sub-formation${\rightarrow}$fruticose lichen, moss cushion sub-formation (Andreaea sociation)${\rightarrow}$fruticose lichen, and moss cushion sub-formation (Usnea sociation), according to the order of snow melting. These directional development stages are shown in gradual change in small area with the snow melting phenomena. However, in the snow-free area, where water is sufficiently supplied, it is expected that moss carpet sub-formation (Sanionia sociation) will be developed. Vegetation development in the small area with the snow melting phenomena, depending on differences of resistance on snow kill and moisture settled by species in according to the time of snow melting, tolerance model to form community is followed. Conclusions: The research results explain the development of vegetation in the Antarctic tundra and its spatial distribution according to the period for growth of lichens and mosses in the summer time by differences of snow melting in the small area. In the future, if research for the community development process in a large scale will be done, it will be helpful to figure out temporal and spatial dynamic of vegetation in the Antarctic tundra where snow and glaciers melt rapidly due to climatic warming.

• Ocean and Polar Research
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• 제24권3호
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• pp.279-287
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• 2002

Successive 24 snow samples, collected from a 1.2m snow pit at a site on the summit of Main Dome in King George Island, Antarctic Peninsula, were measured for heavy metals such as Pb, Cd, Cu, and Zn and other chemical species. The mean concentrations of heavy metals are 3.48pg/g for Pb, 0.10pg/g for Cd, 16.6 pg/g for Cu and 15.8 pg/g for Zn, respectively. Pb and Cd concentrations observed in our samples are very comparable to those reported for recent snow at other Antarctic sites, while Zn and Cu levels are much higher than those at other sites. The annual fallout fluxes of all heavy metals approximately calculated are, however, much greater in King George Island than at other sites. With respect to the estimates of natural contributions, sea salt spray is found to be a major contributor to Cd and Zn inputs to the snow and minor to Cu inputs. On the other hand, the anthropogenic input can account for a large part of Pb concentrations. A tentative estimate represents that local emissions could be responsible for more than half of the excess Pb flux to the snow in King George Island.