• Journal of Ocean Engineering and Technology
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• v.34 no.6
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• pp.394-405
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• 2020

To assess the station-keeping performance of floating structures in the Arctic region, the ice load should be considered along with other environmental loads induced by waves, wind, and currents. However, present methods for performance evaluation in the time domain are not effective in terms of time and cost. An ice load generation module is proposed based on the experimental data measured at the KRISO ice model basin. The developed module was applied to a time domain simulation. Using the results of a captive model test conducted in multiple directions, the statistical characteristics of ice loads were analyzed and processed so that an ice load corresponding to an arbitrary angle of the structure could be generated. The developed module is connected to commercial dynamic analysis software (OrcaFlex) as an external force input. Station-keeping simulation in the time domain was conducted for the same floating structure used in the model test. The mooring system was modeled and included to reflect the designed operation scenario. Simulation results show the effectiveness of the proposed ice generation module and its application to station-keeping performance evaluation. Considering the generated ice load, the designed structure can maintain a heading angle relative to ice up to 4°. Station-keeping performance is enhanced as the heading angle conforms to the drift direction. It is expected that the developed module will be used as a platform to verify station-keeping algorithms for Arctic floating structures with a dynamic positioning system.

• Korean Journal of Remote Sensing
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• v.30 no.6
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• pp.809-816
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• 2014

Ocean Color products have been used to understand marine ecosystem. In high latitude region, ice melting optically influences the ocean color products. In this study, we assessed optical properties in fjord around Svalbard Arctic sea, and estimated distribution of chlorophyll-a and suspended sediment by using high resolution satellite data, Landsat-8 Operational Land Imager (OLI). To estimate chlorophyll-a and suspended sediment concentrations, various regression models were tested with different band ratio. The regression models were not shown high correlation because of temporal difference between satellite data and in-situ data. However, model-derived distribution of ocean color products from OLI showed a possibility that fjord and coastal areas around Arctic Sea can be monitored with high resolution satellite data. To understand climate change pattern around Arctic Sea, we need to understand ice meting influences on marine ecosystem change. Results of this study will be used to high resolution monitoring of ice melting and its influences on the marine ecosystem change at high latitude. KOPRI (Korea Polar Research Institute) has been operated the Dasan station on Svalbard since 2002, and study was conducted using Arctic station.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.1
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• pp.15-25
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• 2017

In recent years, polar research has been focused on climate change, natural resources, and development of a new North Pole Route. Since 2010, the Korea Polar Research Institute has been collecting various in situ data from the Arctic/Antarctic oceans using ARAON, which is the first effort of Korea toward leading global polar research. As a part of these activities, a web-based GIS service was developed to collect in situ data and to standardize data formats. Visualizations of in situ measurements and thematic maps were also developed to improve both the quantitative and qualitative quality of polar ocean research, and to increase accessibility of polar oceanographic data. This system will ultimately share all of the data acquired from the Arctic/Antarctic oceans with international research groups.

• The Korean Journal of Quaternary Research
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• v.5 no.1
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• pp.1-13
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• 1991

The distribution of cryophilous arctic-alpine and alpine plants in Korea is reviewed in connection with palaeoenvironment, along with a discussion to their origins, patterns of migration, and their refugia. At present, the estimated number of Korean arctic-alpine and alpine species is 419, and this includes 75 arctic-alpine species, 239 alpine species and 105 Korean endemic alpine species. The disjunctive distribution of cryophilous arctic-alpine and alpine plants is likely to be due to first, the downslope and southward expansion of those species towards the Korean peninsula as a primary refugia from the arctic region as the Pleistocene glacial phases approached, and then their subsequent isolation upslope in mountain areas toward a secondary refugia as the interglacial and post-glacial climatic ameliorations followed; secondly, the expansion of forest tree communities on lowland and montane areas subsequent to the end of the Pleistocene has had the effect of dividing formerly high mountains as a result of the increased competition; and thirdly, the general disapperance or restriction of available habitats for arctic-alpine and alpine species because of post-glacial climatic amelioration. The existence of 139 alpine species exclusively in the north of Korea may be due to the following reasons; first, frequent exchanges of alpine floras with other neighbouring East Asian regions would have been facilitated; secondly, there are numerous high mountains available for the alpine plants to survive and prosper during the post-glacial period; thirdly, the existence of easy accesses between mountains within the north, which has enabled alpine floras to migrate when necessary; and finally, the availability of diverse environments and habitats for the alpine flora of the north. However, the continued survival of those species in Korea at the world's or East Asia's southernmost limits of their distribution for many species is in danger if global warming associated with the greenhouse effect takes place.

• Korean Journal of Microbiology
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• v.50 no.2
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• pp.164-168
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• 2014

The ecosystem of the Arctic region has been increasingly affected by global warming. Archaeal ammonia monooxygenase alpha subunit coding gene (amoA) which is a key enzyme for nitrification was used to investigate the effect of runoff water of ice melt on microbial community of nitrogen cycle. The archaeal amoA genes at coastal area of Svalbard, Arctic region were PCR-amplified and sequenced after clone library construction. Analysis of archaeal amoA gene clone libraries suggested that the station 188 which is in the vicinity to the area of runoff water harbor lower ammonia-oxidizing archaeal diversity than the station 176 and 184. The average amino acid sequence identity within all archaeal amoA gene clones was 94% (with 91% nucleotide sequence identity). While all the clones of the station 188 were affiliated with Nitrosoarchaeaum clade containing strains isolated from low-salinity and terrestrial environments, about 45% of total clones of the station 176 and 184 were related to marine Nitosopumilus clade. Interestingly, other typical archaeal amoA gene clones of thaumarchaeal I.1b clade frequently retrieved from terrestrial environments was identified at station 188. Microbial community of nitrogen cycle in marine sediment might be affected by input of sediments caused by runoff glacier melt waters.

• Korean Journal of Remote Sensing
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• v.25 no.5
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• pp.423-434
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• 2009

The Arctic environment is sensitive to change of sea-ice distribution. The increase and decrease of sea ice work to an index of globe warming progress. In order to predict the progress of hereafter earth global warming, continuous monitoring regarding a change of the sea ice area in the Arctic should be performed. The remote sensing based on an artificial satellite is most effective on the North Pole. The sea ice observation using a passive microwave sensor has been continued from 1970's. The determination of sea ice extent and ice type is one of the great successes of the passive microwave imagers. In this paper, to investigate the seasonal and inter-annual variation of sea-ice distribution we used here the sea ice data from July 2002 to May 2009 around the Arctic within $60^{\circ}N$ for the AMSR-E 12.5km sea-ice concentration, a passive microwave sensor. From an early analysis of these data, the arctic sea-ice extent has been steadily decreasing at a rate of about 3.1%, accounting for about $2{\times}10^5\;km^2$, which was calculated for the sea-ice cover reaching its minimum extent at the end of each summer. It is also revealed that this trend corresponds to a decline in the multi-year ice that is affected mainly by summer sea surface and air temperature increases. The extent of younger and thinner (first-year) ice decreased to the 2007 minimum, but rapidly recovered in 2008 and 2009 due to the dramatic loss in 2007. Seasonal variations of the sea-ice extent show significant year-to-year variation in the seasons of January-March in the Barents and Labrador seas and August-October in the region from the East Siberian and Chukchi seas to the North Pole. The spatial distribution of multi-year ice (7-year old) indicates that the perennial ice fraction has rapidly shrunk recently out of the East Siberian, Laptev, and Kara seas to the high region of the Arctic within the last seven years and the Northeast Passage could become open year-round in near future.

• Korean Journal of Remote Sensing
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• v.34 no.6_2
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• pp.1155-1163
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• 2018

Recently, much attention has been focused on the change and role of the Arctic region due to climate change. Studies using various platforms are being conducted in the polar regions. Among them, monitoring of Arctic cryosphere information using remote sensing is the most important observational role of various scientific activities. This special issue introduces several studies on polar exploration monitoring in polar research. We hope that this special issue contributes to the sharing of information on the role of polar exploration in remote areas, as well as the identification of the current status of domestic polar exploration and remote environmental exploration. We are also looking forward to the efforts of Korean remote sensing experts to find out the persistent polar exploration field and to increase national support.

• Korea Trade Review
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• v.48 no.4
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• pp.121-148
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• 2023

The rapid melting of Arctic sea ice has increased interest in the Northern Sea Route (NSR) as a viable alternative trade route between Europe and Asia. While extensive research has examined its competitiveness in terms of technical feasibility, safety, profitability, and environmental impact, the topic of the NSR ports remains relatively underrepresented in the literature. Hence, this study aims to contribute to the existing research by assessing the efficiency of 17 NSR ports to gain insights into their operations and identify areas for improvement using models of Data Envelopment Analysis(DEA). The obtained results show that efficient ports mainly belong to the western NSR region, with ports like Murmansk and Varandei consistently demonstrating high efficiency and constant returns to scale. Several ports, such as Onega, Arkhangelsk, Naryan-Mar, and Khatanga, showed inefficiencies in the utilization of berths and quay lengths. The findings not only contribute to academic knowledge but also offer practical implications for NSR port authorities, assisting them in making well-informed decisions regarding infrastructure development plans.

• ALGAE
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• v.28 no.3
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• pp.267-280
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• 2013

The marine algal flora of the Keret Archipelago ($66^{\circ}$ N, $33^{\circ}$ E) in the White Sea, Russia was investigated during 2008. Over 250 algal records from more than 15 islands and several sites on the adjoining mainland produced a total of 62 algal species. This raised the total from 56 to 88 species of Chlorophyta (23 species), Phaeophyceae (31 species), Rhodophyta (33 species), and Tribophyceae (1 species) of which seven were new records or verifications of ambiguous records for the White Sea and 11 species are new for the Keret Archipelago. The new or confirmed records included species of Blidingia, Eugomontia, Prasiola, Rosenvingiella, and Ulothrix (Chlorophyta), Acrochaetium, Colaconema (Rhodophyta), and Vaucheria (Tribophyceae). Five species of flowering plants (Aster, Plantago, Triglochin, and Zostera) were associated with the macrophytic algal vegetation of the region. Five fucoid algae in Pelvetia, Fucus, and Ascophyllum provide a picture of a temperate flora. Regardless, the overall species richness is consistent with an arctic nature to the flora. This discrepancy is attributed to the 'filter' provided by the Barents Sea of the Arctic Ocean for post-glacial colonization of the White Sea.

• Atmosphere
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• v.28 no.2
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• pp.153-162
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• 2018

The statistical prediction model for wintertime surface air temperature, that is based on snow cover extent and Arctic sea ice concentration, is updated by considering $El-Ni{\tilde{n}}o$ Southern Oscillation (ENSO) and Quasi-Biennial Oscillation (QBO). These additional factors, representing leading modes of interannual variability in the troposphere and stratosphere, enhance the seasonal prediction over the Northern Hemispheric surface air temperature, even though their impacts are dependent on the predicted month and region. In particular, the prediction of Korean surface air temperature in midwinter is substantially improved. In December, ENSO improved about 10% of prediction skill compared without it. In January, ENSO and QBO jointly helped to enhance prediction skill up to 36%. These results suggest that wintertime surface air temperature in Korea can be better predicted by considering not only high-latitude surface conditions (i.e., Eurasian snow cover extent and Arctic sea ice concentration) but also equatorial sea surface temperature and stratospheric circulation.