• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2009년도 춘계학술대회 논문집
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• pp.190-195
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• 2009

서남극 빙상의 감소 속도는 급격히 가속화되고 있으며, 전 지구적 해수면 상승과 기후변화 예측을 위해 이 지역에 대한 지속적인 관찰이 요구되고 있다. 본 연구에서는 서남극 Canisteo 반도와 주변 지역이 촬영된 2쌍의 ERS-1/2 tandem pair에 4-pass 위상차분간섭기법을 적용하여 위상차분간섭도를 생성하였고, 빙하와 해빙, 그리고 빙붕의 표면 변화를 관찰하였다. 위상차분간섭도에서 센서 방향으로의 변위를 추출한 결과 해안 빙하와 그에 인접한 정착빙은 같은 방향의 움직임을 나타냈다. 특히 빙하와 맞닿은 부분의 정착빙은 그 움직임이 다른 부분에 비해 컸는데, 이는 빙하의 하강 및 유실이 해빙에 영향을 끼치는 것으로 판단된다. 정착빙의 가장자리에 위치한 해빙은 해류의 영향에 기인하는 움직임을 보였으며, 이 해빙의 유형이 부빙 또는 유빙임을 알 수 있었다. 반도 양옆에 위치한 빙붕은 모두 센서 방향으로의 움직임을 보였으나 그 크기에서 차이를 나타냈다. 빙붕의 표면에서는 원형의 국부적 함몰이 다수 관찰되었는데, 이는 남극저층수의 적은 유입으로 인해 형성된 melt pond로 추정된다.

• 공학교육연구
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• 제19권5호
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• pp.57-64
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• 2016

This study is about interdisciplinary education model of using Davis Guggenheim's documentary film on global warming which is a big concern in climate change issues, An Inconvenient Truth. It based on Al Gore's slide speech. Through a course student analyzed the cause and phenomenon of global warming resulted from increase of $CO_2$ by using fossil fuel and its environmental science effects-heat wave, desertification, tornado, hurricane, sea level rise caused by melting glaciers, destroying ecosystem like habitat degradation of wild animals, for example polar bear, extreme cold wave caused by change of ocean currents- of global warming. After, student discussed of efforts to prevent global warming. This educational model is appropriate for lower grade student of environmental engineering and also available for converged majors or general education class.

• 지구물리와물리탐사
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• 제13권1호
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• pp.51-60
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• 2010

남극 킹조지섬 포케이드 빙하의 저면 지형과 내부 모습을 규명하기 위해서 2006년 11월에 4개 조사측선을 따라 헬리콥터 및 지상 레이다(GPR) 탐사를 실시하였다. 혼합위상인 단채널 지상 GPR 자료에 적용한 신호 역대합, f-k 구조보정 속도분석, 유한차분 깊이구조보정 등의 처리과정을 통하여 수직 분해능 향상, 속도함수 추출, 선명한 깊이영상 작성 등을 효과적으로 수행하였다. 헬리콥터 GPR 자료의 경우, 구조보정속도는 공기와 얼음의 2층모델을 가정한 평균제곱근속도로 구하였다. GPR 단연은 울퉁불퉁한 빙저면, 빙하 내부의 미끄러짐면, 운집된 산란잡음 등의 특징적 모습을 보여준다. 기반암까지의 최대 깊이는 포케이드 빙하와 목지들로우스키 빙하 사이의 경계능선 남동사면에 인접한 빙하 골짜기에서 79 m가 넘는다. 빙하 기저수 위에 복잡한 형태의 굴과 수 m의 폭을 갖는 독립된 빈 공간들의 존재를 지상 GPR 자료로부터 해석하였다. 빙하 중단 부근의 GPR 영상은 포토소만의 빙산 형성기작과 관련된 미끄러짐면, 단열, 단층 등의 구조를 보여준다.

• 한국지리정보학회지
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• 제11권4호
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• pp.32-40
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• 2008

온난화는 오늘날 발생하는 다양한 기상재해와 이변의 원인으로 전 세계적으로 중요한 문제점 중에 하나이다. 눈과 빙하는 지구온난화의 영향을 가장 쉽게 보여주는 예이며, 이것들은 높은 반사도 특성으로 지구 냉각에 중요한 역할을 하고 있다. 본 연구에서는 MODIS(Moderate Resolution Imaging Spectroradiometer)센서의 자료를 이용하여 히말라야 산맥내의 만년설 모니터링을 수행하였다. 만년설 감시를 위해서 NDSI(Normalized Differenced Snow Index)를 사용하였으며, NDSI는 위성 영상내에 눈을 감지하기 위해 가시와 단파적외 영역에서 눈의 반사도 특성 차이를 이용한 밴드비율이다. 본 연구에서는 2001년, 2003년, 2006년, 2007년의 9월부터 12월까지의 NDSI를 산출하여 만년설을 감시하였으며, 막연하게 알고 있던 고산지대 만년설에 대한 온난화의 영향을 정량적으로 검증하였다. 검증 결과 2007년이 비해 2001년에 잔설지역이 9월 $71,481km^2$, 10월 $92,760km^2$, 11월 $333,916km^2$ 각각 감소한 것으로 나타났다.

• 한국광물학회:학술대회논문집
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• 한국광물학회.한국암석학회 2003년도 공동학술발표회 논문집
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• pp.66-66
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• 2003

King George island, Antarctica, is mostly covered by ice sheet and glaciers, but the land area is focally exposed for several thousand years after deglaciation. For a mineralogical study of chemical weathering in the polar environment, glacial debris was sampled at the well-developed patterned ground which was formed by long periglaclal process. As fresh equivalents, recently exposed tills were sampled at the base of ice cliff of outlet glaciers and at the melting margin of ice cap together with fresh bedrock samples. Fresh tills are mostly composed of quartz, plagioclase, chlorite, and illite, but those derived from hydrothermal alteration zone contain smectite and illite-smectite. In bedrocks, chlorite was the major clay minerals in most samples with minor illite near hydrothermal alteration zone and interstratified chlorite-smectite in some samples. Smectite closely associated with eolian volcanic glass was assigned to alteration in their source region. Blocks with rough surface due to chemical disintegration showed weathering rinds of several millimeter thick. Comparision between inner fresh and outer altered zones did not show notable change in clay mineralogy except dissolution of calcite and some plagioclase. Most significant weathering was observed in the biotite flakes, eolian volcanic glass, sulfides, and carbonates in the debris. Biotite flakes derived from granodiorite were altered to hydrobiotite and vermiculite of yellow brown color. Minor epitactic kaolinite and gibbsite were formed in the cleaved flakes of weathered biotite. Pyrite was replaced by iron oxides. Calcite was congruently dissolved. Volcanic glass of basaltic andesite composition showed alteration rim of several micrometer thick or completely dissolved leaving mesh of plagioclase laths. In the alteration rim, Si, Na, Mg, and Ca were depleted, whereas Al, Ti, and Fe were relatively enriched. Mineralization of lichen and moss debris is of much interest. They are rich of A3 and Si roughly in the ratio of 2:1 to 3:1 typical of allophane. In some case, Fe and Ti are enriched in addition to Al and Si. Transmission electron microscopy of the samples rich of volcanic glass showed abundant amorphous aluminosilicates, which are interpreted as allophane. Chemical weathering in the King George Island is dominated by the leaching of primary phyllosilicates, carbonates, eolian volcanic glass, and minor sulfides. Authigenesls of clay minerals is less active. Absence of a positive evidence of significant authigenic smectite formation suggests that its contribution to the clay mineralogy of marine sediments are doubtful even near the maritime Antarctica undergoing a more rapid and intenser chemical weathering under more humid and milder climate.

• International Journal of Naval Architecture and Ocean Engineering
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• 제10권3호
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• pp.361-366
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• 2018

Ice crushing occurs in many situations that involve a sliding frictional component such as sports involving ice-contact, ice interaction with ship hulls, and ice-on-ice sliding/crushing within glaciers and between interacting sea ice floes. Ice crushing-friction tests were conducted in the lab at $-10^{\circ}C$ using a set of acrylic ice-crushing platens that included a flat smooth surface and a variety of high-roughness surfaces with regular arrays of small prominences. The experiments were part of Phase II tests of the Blade Runners technology for reducing ice-induced vibration. Ice was crushed against the platens where the ice movement had both a vertical and a horizontal component. High-speed imaging through the platens was used to observe the ice contact zone as it evolved during the tests. Vertical crushing rates were in the range 10-30 mm/s and the horizontal sliding rates were in the range 4.14-30 mm/s. Three types of freshwater ice were used. Friction coefficients were extraordinarily low and were proportional to the ratio of the tangential sliding rate and the normal crushing rate. For the rough surfaces all of the friction coefficient variation was determined by the fluid dynamics of a slurry that flowed through channels that developed between leeward-facing facets of the prominences and the moving ice. The slurry originated from a highly-lubricating self-generating squeeze film of ice particles and melt located between the encroaching intact ice and the surfaces.

• 한국주거학회논문집
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• 제25권2호
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• pp.11-18
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• 2014

This study looked at designing, building and operating temporary camp, the first structures that South Korea built in the Antarctica. While there may be differences in accordance with the topography, ground surfaces in the Antarctica are covered broken stones, glaciers and snow. Hence, such topographical characteristics should be taken into account when conducting any construction work. To ensure successful assembly construction in the Antarctica using modules, prior trial assembly work should be done in Korea to identify any possible trouble in the actual construction process. Assuming that the workers will have to spend at least one winter in the temporary camp, the work will be more severely affected by adverse weather conditions and snow drift, resulting in the need to clear snow. This can be by designing roofs with curved surfaces. Also, quantitative effects will need to be verified through simulation and actual measurement. It will also be necessary to assess the camp's thermal environment and examine its air-conditioning methods. To identify the temporary camp's thermal system, the temperatures and humidities were measured, and the heating system was designed not to offer automatic control or desired value selection functions.

• Journal of Astronomy and Space Sciences
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• 제33권4호
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• pp.295-304
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• 2016

The atmosphere strongly affects the Earth's spin rotation in wide range of timescale from daily to annual. Its dominant role in the seasonal perturbations of both the pole position and spinning rate of the Earth is once again confirmed by a comparison of two recent data sets; i) the Earth orientation parameter and ii) the global atmospheric state. The atmospheric semi-diurnal tide has been known to be a source of the Earth's spin acceleration, and its magnitude is re-estimated by using an enhanced formulation and an up-dated empirical atmospheric S2 tide model. During the last twenty years, an unusual eastward drift of the Earth's pole has been observed. The change in the Earth's inertia tensor due to glacier mass redistribution is directly assessed, and the recent eastward movement of the pole is ascribed to this change. Furthermore, the associated changes in the length of day and UT1 are estimated.

• 대한원격탐사학회지
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• 제37권1호
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• pp.1-11
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• 2021

This study measures the change of ice flow velocity of David Glacier, one of the fast-moving glaciers in East Antarctica that drains through Drygalski Ice Tongue. In order to effectively observe the rapid flow velocity, we applied the offset tracking technique to Sentinel-1A SAR images obtained from 2016 to 2020 with 36-day temporal baseline. The resulting velocity maps were averaged and the two relatively fast points (A1 and A2) were selected for further time-series analysis. The flow velocity increased during the Antarctic summer (around December to March) over the four years' observation period probably due to the ice surface melting and reduced friction on the ice bottom. Bedmap2 showed that the fast flow velocities at A1 and A2 are associated with a sharp decrease in the ice surface and bottom elevation so that ice volumetric cross-section narrows down and the crevasses are being created on the ice surface. The local maxima in standard deviation of ice velocity, S1 and S2, showed random temporal fluctuation due to the rotational ice swirls causing error in offset tracking method. It is suggested that more robust offset tracking method is necessary to incorporate rotational motion.

• 한국해양공학회지
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• 제37권5호
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• pp.215-224
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• 2023

While melting glaciers due to global warming have facilitated the development of polar routes, Arctic vessels require reliable anti-icing methods to prevent hull icing. Currently, the existing anti-icing method, i.e., the heating coil method, has disadvantages, such as disconnection and power inefficiency. Therefore, a carbon nanotube-based surface heating element method was developed to address these limitations. In this study, the numerical analysis of the surface heating element method was performed using ANSYS. The numerical analysis included conjugate heat transfer and computational fluid dynamics to consider the conduction solids and the effects of wind speed and temperature in cold environments. The numerical analysis method of the surface heating element method was validated by comparing the experimental results of the heating coil method with the numerical analysis results (under the -30 ℃ conditions). The surface heating element method demonstrated significantly higher efficiency, ranging from 56.65-80.17%, depending on the conditions compared to the heating coil method. Moreover, even under extreme environmental conditions (-45 ℃), the surface heating element method satisfied anti-icing requirements. The surface heating element method is more efficient and economical than the heating coil method. However, proper heat flux calculation for environmental conditions is required to prevent excessive design.