• Ocean and Polar Research
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• v.33 no.1
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• pp.1-11
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• 2011

This study describes measurements of fast ice recorded on May 23, 2009, in Kongsfjorden (translated as 'Kongs Fjord'), an inlet on the west coast of Spitsbergen in the Svalbard Archipelago. Seasonal fast ice is an important feature for Svalbard fjords, both in relation to their physical environment and also the local ecosystem, since it grows seaward from the coast and remains in place throughout the winter. Ice thickness, snow, ice properties, and wind speed were measured, while SAR (Synthetic Aperture Radar) data was observed simultaneously observed two times from ALOS-PALSAR (L-band). Measured ice thickness was about 25-35 cm while the thickness of ice floe broken from fast ice was measured as 10-15 cm. Average salinity was 1.9-2.0 ppt during the melting period. Polarimetric data was used to extract H/A/alpha-angle parameters of fast ice, ice floe, snow and glacier, which was classified into 18 classes based on these parameters. It was established that the area of fast ice represents surface scattering which indicates low and medium entropy surface scatters such as Bragg and random surfaces, while fast ice covered with snow belongs to a zone of low entropy surface scattering similar to snow-covered land surfaces. The results of this study will contribute to various interpretations of interrelationships between H/A/alpha parameters and the wave scattering Phenomenon of sea ice.

• Ocean and Polar Research
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• v.26 no.2
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• pp.121-132
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• 2004

Concentrations of Al, As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn were determined in four arctic brown algae (Laminaria saccharina, L. digitata, Alaria esculenta, Desmarestia aculeata) in an attempt to examine for their metal accumulation capacity and also to assess their contamination levels. Macroalgae were collected from shallow subtidal waters (<20m) of Kongsfjorden (Kings Bay) on Spitsbergen during the period of the late July to early August 2003. Metal concentrations highly varied between sampling sites, species and tissue parts. Input of melt-water laden with terrigenous sediment particles seemed to have a large influence on baseline accumulations of some metals (Al, Fe, Mn, Pb etc.) in the macroalgae, causing a significant spatial variation. There were also significant concentration differences between the young and old tissue parts in L. saccharina, L. digitata and A. esculenta. While Al, Fe, Mn, Pb were higher in the perennial parts (stipes and holdfast below meristematic region), Cd and As concentrations were significantly higher in the young blades above the meristematic region. Zn and Cr, on the other hand, showed little differences between the tissue parts. The highest metal concentrations were found in D. aculeata, which seems to be due to its filamentous fine branches leading to high surface/volume ratios. The lowest concentrations were found in the two Laminaria spp., the blades of which are thicker than D. aculeata and A. esculenta. No distinct signs of contamination were detected in the brown algal species analyzed. Added to this, the results of the present studies suggest the potential utility of L. saccharina, L. digitata and A. esculenta as biomonitors for metal pollution monitoring in this area.

• Journal of the Korean earth science society
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• v.32 no.1
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• pp.73-83
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• 2011

A new method was developed to better understand the principle of Coriolis force. We also investigated the understanding of 5 10th grade students and analyzed their responses. Since no clear explanation about the nature of a rotating disk is provided in school textbooks, it tends to be misunderstood as the earth surface revolving on its axis pointing to the North Pole. This study was carried out focusing on the fact that a rotating disk is the tangential plane at arbitrary latitude. Results showed that there are changes in students' conceptions on the principle of Coriolis force with a new understanding of the rotating disk. In conclusion, a new method used in this study helped students better understand the link between Coriolis force and rotating disk. The method would be helpful to clarify the principle of Coriolis force in school science.

• Atmosphere
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• v.24 no.1
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• pp.29-38
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• 2014

A characteristic of snowfall and minimum temperature variability in South Korea with respect to the variability of Arctic Oscillation (AO) was investigated. The climatic snowfall regions of South Korea based on daily new fresh snowfall data of 59 Korea Meteorological Administration (KMA) stations data corresponding to the sign of AO index during December to February 1979~2011 were classified. Especially, the differences between snowfalls of eastern regions and that of western regions in South Korea were seen by each mean 1000hPa geopotential height fields, which is one of physical structure, for the selected cases over the East Asia including the Korean Peninsula. Daily minimum temperature variability of 59 KMA station data and daily AO index during the same period were investigated using Cyclo-stationary empirical orthogonal function (CSEOF) analysis. The first CSEOF of wintertime daily AO index and that of minimum temperature of 59 KMA stations explain 33% and 66% of total variability, respectively. Correlation between principal component time series corresponding to the first CSEOF of AO index and that of temperature at the period of 1990s is over about -0.7 when that of AO index leads about 40 days.

• Ocean and Polar Research
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• v.31 no.2
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• pp.213-218
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• 2009

We examined the intracellular antioxidative effects of 20 Arctic seaweed extracts in Raw 264.7 cells. Each seaweed species was subjected to extraction using acetone/dichloromethane and methanol, respectively, after which the extracts were combined and used as the test sample. The antioxidant ability of all 20 seaweeds extracts was evaluated using four different activity tests, including the degree of occurrence of intracellular reactive oxygen species (ROS), $ONOO^-$, and lipid peroxidation in Raw 264.7 cells, as well as the extent of oxidative damage of genomic DNA purified from Raw 264.7 cells. Crude extracts from Monostroma obscurum, Alaria esculnta, Laminaria digitata, Desmarestia aculeata, Chorda filum, Ptilota seriata, Phycidrys rubens, Devaleraea ramentacea and Palmaria palmata exhibited significant scavenging effects on the generation of intracellular ROS. Among them, Monostroma obscurum and Phycidrys rubens significantly inhibited membrane lipid peroxidation and DNA oxidation. Moreover, Phycidrys rubens exhibited scavenging effects on peroxynitrite generated from SIN-1.

• Journal of Energy Engineering
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• v.25 no.4
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• pp.133-140
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• 2016

Thermoelectric generator, which is known as using Seebeck effect, have been widely applied in many industrial parts, for instance, from submarine to equipments capable of producing hot or cooling water. Its usefulness was verified in terms of producing electric power using temperature difference and vice versa. Application on thermoelectric generator has been mainly forced on exhaust gas of automotive engine so far. In this study, the possibility was investigated whether electric power could be produced by using cooling water in automotive engine. As the result, it showed that electric power had differences depending on shapes of power auxiliary apparatus and, in this experiment, maximum of electric power was 1.5 voltage.

• Journal of Ocean Engineering and Technology
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• v.32 no.3
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• pp.184-191
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• 2018

Recently, as sea ice in the Arctic has been decreasing due to global warming, it has become easier to develop oil and gas resources buried in the Arctic region. As a result, Russia, the United States, and other Arctic coastal states are increasingly interested in the development of oil and gas resources, and the demand for offshore structures to support Arctic sea resources development is expected to significantly increase. Since offshore structures operating in Arctic regions need to secure safety against various drifting ice conditions, the concept of an ice-strengthened design is introduced here, with a priority on calculation of ice load. Although research on the estimation of ice load has been carried out all over the world, most ice-load studies have been limited to estimating the ice load of the icebreaker in a non-oblique state. Meanwhile, in the case of Arctic offshore structures, although it is also necessary to estimate the ice load according to oblique angles, the overall research on this topic is insufficient. In this paper, we suggest algorithms for calculating the ice load of managed ice (pack ice, 100% concentration) in an oblique state, and discuss validity. The effect of oblique angle according to estimated ice load with various oblique angles was also analyzed, along with the impact of ship speed and ice thickness on ice load.

• Journal of the Korean Geographical Society
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• v.43 no.4
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• pp.495-510
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• 2008

Vaccinium vitis-idaea or lingonberry, a typical arctic-alpine plant, is common on the circumpolar regions and alpine belts of the Northern Hemisphere, and also occurs on the alpine and subalpine belts of the Korean Peninsula, including Mt. Sorak and Hongchon. Vaccinium vitis-idaea at the elevation of c. 350m a.s.l. of Hongchon is found on the wind hole area with cool summer, and mild winter. Vaccinium vitis-idaea at Hongchon is regarded as the glacial relict of the Pleistocene period, and shows a disjunctive distribution, along with the alpine and subalpine belts of the northern and central Korea since the Holocene period. Present vertical range of Vaccinium vitis-idaea between Mt. Sorak and Hongchon might indicates that the temperatures during the glacial epoch was colder than today, down to -6 to $-7^{\circ}C$ Vaccinium vitis-idaea at this fragile wind hole site could be endanger if current global warming trends continues, and anthropogenic activities become serious.

• Ocean and Polar Research
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• v.34 no.1
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• pp.101-110
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• 2012

In this study, we attempted to provide Korean names to the arctic vascular plants observed around the Dasan Korean Arctic Station and Longyearbyen in Spitsbergen Island, in the Arctic region. To obtain recognizable results, plants were named according to the following naming rules. (1) When Korean names already existed, those names were used. (2) When there was no Korean name for a plant species, a scientific name for the plant was translated into a Korean name. (3) If the meaning of the scientific name was unclear, an English common name was translated into Korean name. (4) If the scientific names had meaning to the Arctic inhabitation, the Korean names included the word 'Buk-geuk'. (5) If the distribution of the plant was limited to the Arctic area or the original species lived in the polar region, the Korean name included the word 'Buk-geuk'. (6) If the plant had no Korean generic name, a particular suffix '~a-jae-bi' was added to the closely related genus name of the plant species, or a new Korean genus name was used by translating a common English name. (7) If the same generic name had two or more Korean names, a generic name that better reflected the characteristics of the plant was selected. In this paper, we reported Korean names for 46 plants species belonging to 15 families and 28 genera. Eight plants had an existing Korean name and the other species were given new Korean names based on the criteria outlined above. We also made new Korean generic names for three genera, Braya, Micranthes and Cassiope.

• Ocean and Polar Research
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• v.36 no.3
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• pp.303-318
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• 2014

The rising global demand for energy resources may lead to greater interest in the Arctic region. Since it has various resources, such as oil and gas, and large potential as a strategic location in exploration and production (E&P), there is likely to occur island sovereignty issues between the five arctic costal states and other countries. While global warming has led to the opening of the Northeast Passage and the Northwest Passage, several obstacles may impede the development of this area such as the low temperature environment, infrastructure problems in a limited area, flow assurance, environmental regulations, etc. To overcome these problems, various techniques have been applied in the exploration, development, production, transportation, and environment fields and it seems to be made technical development in extreme environment. In this study, the E&P status of representative states and development technologies in the Arctic region have been summarized with regard to carrying out E&P related to drilling, development, production, and operation in oil and gas fields. Furthermore, environmental factors have been taken into account to enhance progress with regard to E&P and ensure sustainable development in the Arctic. On that basis, it will be possible to secure oil and gas field development, production technology and R&D infrastructure in the Arctic.