• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.72.4-73
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• 2018

북극 스발바르의 사면 지형에는 걸리가 발달되어 있다. 이러한 걸리는, 그 성인에는 여러 의견이 있으나, 화성에도 중고위도를 중심으로 다수 분포한다. 화성의 걸리는 2000년대에 들어 비로소 본격적으로 규명되고 있으나, 지형적 특성으로 인한 탐사의 한계로 지구에 분포하는 유사지형을 통한 비교 연구가 일반적이다(Costard, et al. 2007 등). 이 연구에서는 스발바르의 주도 롱이어비엔에서 UAV을 이용하여 획득한 DEM으로 스발바르 걸리를 측량하고, 이를 화성 중위도의 테라 사이메리아, 테라 시레넘, 노아 키스 테라에 분포하는 걸리와 비교하였다. Longyearbreen 빙하 전방에 위치한 사면을 UAV로 촬영하고, 이를 SfM-MVS(Structure from Motion & MultiView Stereo) 기법으로 3차원 점군 모델과 고해상도 DEM을 제작하여 분석하였다. 화성의 경우 MRO궤도 탐사선이 촬영한 HiRise DTM을 이용하여 분석하였다. 두 걸리는 기후와 지질 조건에 차이가 있음에도 불구하고 유사한 패턴을 보였다. 특히 테라 사이메리아에 위치한 걸리와 롱이어비엔 북사면의 걸리는 기준거리, 단면적, 폭, 경사, 제방 두께 등에서 상당한 정량적 유사관계가 있었다. 이는 두 행성의 걸리가 유사한 성인 및 형성 프로세스를 거쳤을 가능성을 시사한다. 측량 기법과 UAV 의 안정성을 개선시키면 지형 모델의 품질 향상 및 극지에서의 UAV 운용이 용이해질 것으로 기대된다. 또한 스발바르의 기후 요소 및 물리량 적용은 향후 화성 지형연구에도 응용할 수 있을 것으로 사료된다.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.4
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• pp.52-67
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• 2020

Recently, the Arctic has been exposed to snow-covered land due to melting permafrost every year, and the Korea Geographic Information Institute(NGII) provides polar spatial information service by establishing spatial information of the polar region. However, there is a lack of spatial information on vegetation sensitive to climate change. This research used a multi-temporal Sentinel-2 image to perform land cover classification of the Ny-Ålesund in Arctic Svalbard. In the pre-processing step, 10 bands and 6 vegetation spectral index were generated from multi-temporal Sentinel-2 images. In image-classification step is consisted of extracting the vegetation area through 8-class land cover classification and performing the vegetation species classification. The image classification algorithm used Random Forest to evaluate the accuracy and calculate feature importance through Out-Of-Bag(OOB). To identify the advantages of multi- temporary Sentinel-2 for vegetation classification, the overall accuracy was compared according to the number of images stacked and vegetation spectral index. Overall accuracy was 77% when using single-time Sentinel-2 images, but improved to 81% when using multi-time Sentinel-2 images. In addition, the overall accuracy improved to about 83% in learning when the vegetation index was used additionally. The most important spectral variables to distinguish between vegetation classes are located in the Red, Green, and short wave infrared-1(SWIR1). This research can be used as a basic study that optimizes input characteristics in performing the classification of vegetation in the polar regions.

• Journal of Satellite, Information and Communications
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• v.10 no.3
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• pp.102-108
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• 2015

With the constantly increasing demand of domestic and oversea satellite images, there is also a growing demand to rapidly acquire images after the satellite image collection planning of KOMPSAT-2/3/5. Therefore, it has been increasing to use the korea ground station and oversea ground station to keep pace with increased demand. The KARI is operating Data Ingestion System of the KOMPSAT-2/3 in Svalbard, where the satellite images have been received at least four or six times a day. The KARI is planning to operate oversea receiving system for KOMPSAT-5/3A. This paper introduces the polar data ingestion system operating in Norway, and presents the process of design and development for Polar Integration receiving system in preparation of multiple satellite operation.

• Microbiology and Biotechnology Letters
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• v.44 no.2
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• pp.171-179
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• 2016

Recent succession of soil microorganisms and vegetation has occurred in the glacier foreland, because of glacier thawing. In this study, whole microbial communities, including bacteria, archaea, and eukaryotes, from the glacier foreland of Midtre Lovénbreen in Svalbard were analyzed by metagenome sequencing, using the Ion Torrent Personal Genome Machine (PGM) platform. Soil samples were collected from two research sites (ML4 and ML7), with different exposure times, from the ice. A total of 2,798,108 and 1,691,859 reads were utilized for microbial community analysis based on the metagenomic sequences of ML4 and ML7, respectively. The relative abundance of microbial communities at the domain level showed a high proportion of bacteria (about 86−87%), whereas archaeal and eukaryotic communities were poorly represented by less than 1%. The remaining 12% of the sequences were found to be unclassified. Predominant bacterial groups included Proteobacteria (40.3% from ML4 and 43.3% from ML7) and Actinobacteria (22.9% and 24.9%). Major groups of Archaea included Euryarchaeota (84.4% and 81.1%), followed by Crenarchaeota (10.6% and 13.1%). In the case of eukaryotes, both ML4 and ML7 samples showed Ascomycota (33.8% and 45.0%) as the major group. These findings suggest that metagenome analysis using the Ion Torrent PGM platform could be suitably applied to analyze whole microbial community structures, providing a basis for assessing the relative importance of predominant groups of bacterial, archaeal, and eukaryotic microbial communities in the Arctic glacier foreland of Midtre Lovénbreen, with high resolution.

• Korean Journal of Remote Sensing
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• v.34 no.3
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• pp.495-506
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• 2018

Global interest in climate change and sea level rise has led to active research on the velocities of glaciers. In studies about the velocity of glaciers, in-situ measurements can obtain the most accurate data but have limitations to acquire periodical or long-term data. Offset tracking using SAR is actively being used as an alternative of in-situ measurements. Offset tracking has a limitation in that the accuracy of observation is lower than that of other observational techniques, but it has been improved by recent studies. Recent studies in the $Uv{\hat{e}}rsbreen$ glacier area have shown that glacier altitudes decrease at a rate of 1.5 m/year. The glacier displacement velocities in this region are heavily influenced by climate change and can be important in monitoring and forecasting long-term climate change. However, there are few concrete examples of research in this area. In this study, we applied the improved offset tracking method to observe the two-dimensional velocity in the $Uv{\hat{e}}rsbreen$ glacier. As a result, it was confirmed that the glacier moved at a maximum rate of 133.7 m/year. The measruement precisions for azimuth and line-of-sight directions were 5.4 and 3.3 m/year respectively. These results will be utilized to study long-term changes in elevation of glaciers and to study environmental impacts due to climate change.