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観測隊における情報通信基盤の現状と計画
Full text link第20回南極設営シンポジウム
2024年6月25日（火）
場所：国立極地研究所極地観測棟3F，オンライン
主催：国立極地研究所南極観測センターconference outpu
昭和基地のゼロエミッションに向けたクラウド型エネルギー管理手法の研究
Full text link第20回南極設営シンポジウム
2024年6月25日（火）
場所：国立極地研究所極地観測棟3F，オンライン
主催：国立極地研究所南極観測センターconference outpu
低体温になりにくい汗処理ができるインナー
Full text link第20回南極設営シンポジウム
2024年6月25日（火）
場所：国立極地研究所極地観測棟3F，オンライン
主催：国立極地研究所南極観測センターconference outpu
Observations of two juvenile southern elephant seals hauling out on the Soya Coast, Lützow-Holm Bay, East Antarctica
Full text linkWe report observations of two juvenile southern elephant seals (SES), Mirounga leonina, hauling out on the Soya Coast, Lützow-Holm Bay, East Antarctica, in January 2019. To our knowledge, there have been no previous reports of SES hauling out in this region despite frequent biological research activities under the Japanese Antarctic Research Expedition since the 1960s. One juvenile seal was observed resting at the shore of Lake Suribachi Ike (69° 28′ 58′′S, 39° 39′ 21′′E) in Skarvsnes, located 1.2 km inland from the closest coastline, on 26 January 2019. Another juvenile seal was observed on the seashore of Langhovde (69° 12′ 54′′S, 39° 37′ 31′′E) on 30 January 2019. Both SES showed no signs of molting. At the time of our observations, Lützow-Holm Bay was covered with fast sea ice, extending >80 km from the observation sites, suggesting that the SES penetrated the fast sea ice area using cracks and leads for breathing to reach the snow/ice-free coastline.departmental bulletin pape
Critical seasonal conditions in the reindeer-herding year: A synopsis of factors and events in Fennoscandia and northwestern Russia
No full textIn this article, we identify what herders in Fennoscandia and northwestern Russia see as critical conditions and events in the annual reindeer herding cycle. Indigenous Sámi and Yamal reindeer herders identify eight seasons, each of which has crucial importance in its own way. Differences in perception between Fennoscandian and northwestern Russian reindeer herders about good and bad seasonal conditions are based on the degree of climatic and geographic variation, herd control and the variety of simultaneous pressures on pastures. The scope and speed of ongoing climate change in the Arctic will profoundly modify these conditions, and consequently shape critical events and outcomes in reindeer herding. The resulting challenges need to be assessed in the context of social and economic dynamics. Reindeer herders throughout Fennoscandia and Russia are concerned about future prospects of their livelihood. To adapt to climate change and develop new strategies, reindeer herders must have access to pastures; they must retain their mobility and flexibility; and their participation in land-use decisions must be endorsed.journal articl
Simulation of crude oil slick on ice infested sea water
No full textA three-dimensional numerical model based on the smoothed particle hydrodynamics (SPH) method is utilized to model such interactions. The effects from air and water are well captured using suitable force components and without explicit inclusion of air and water phases. This reduces the four-phase SPH model into a two-phase model, significantly reducing computational costs and potentially enabling the use of this model for large-scale simulations. This study includes two simulation domain size. The results show that the remained oil slick in the icy domain is completely depend on properties of different crude oils and current velocity. Then we performed a numerical experiment to study the effects of different ice parameters (e.g., ice concentration, floe shape) on the drift of fresh and weathered oil. Ice fields with the size of 750 m x 1350 m are used in the experiment. The ice concentration varies between 30%, 50% and 70%. Quadrilateral and circular ice floes, in addition to real-shape floes digitize from an aerial image are all used in the experiment. Oil spills of 1257 ㎥ are released in the open water and later drift into the ice under the influence of steady current of 50 cm/s. The type of spilled crude oil varies from fresh Troll B, Troll B 250 °C, and Troll B 250 °C and 75%emuls. The behavior of oil spills while crossing through the ice infested area are investigated by measuring the thickness of crude oil, the average and maximum distance traveled by crude oil.journal articl
Thermal germination characteristics of three High Arctic plants: Implications for their response to climate warming
No full textAlthough temperature plays a crucial role in governing seed reproduction in High Arctic plants, little is known about the germination response of these plants to climate warming. We conducted a germination experiment to examine the thermal germination characteristics of three common High Arctic plant species in Svalbard: Dryas octopetala, Oxyria digyna, and Salix polaris. We exposed the seeds to two temperature regimes: gradually increasing and decreasing temperatures between 4 and 15 °C. Additionally, we measured the ground surface temperatures at the study site. All three High Arctic plant species exhibited no specific temperature requirements for germination, with minimum germination temperatures falling within the range of 4–8 °C. Based on the ground surface temperature data, the period during which the weekly average ground surface temperature exceeded this minimum germination temperature range (period available for germination) spanned from mid-June to mid-August. By simulating a warming scenario of 2 and 4 °C, we estimated that the onset of the period available for germination would advance by 1–2 and 2–3 weeks, respectively. Furthermore, our results suggest the possibility of autumn germination in the High Arctic region under future warming conditions.journal articl
Phytoplankton community structure during the melting phase of the land-fast ice in Prydz Bay, east Antarctica
No full textPhytoplankton, the primary producers of all aquatic systems, form the base of the marine food web. Any change in the environmental settings of the given ecosystem will affect the phytoplankton community structure of the region. In the present work, water sampling was carried out from the poorly explored polar region, beneath the sea ice during the melting phase of land-fast ice near Indian Antarctic Research Station Bharati in Prydz Bay, East Antarctica. The water samples were analyzed for phytoplankton species diversity, nutrients, temperature, salinity, and Chlorophyll a (Chl a). Our observations indicate marked variations in phytoplankton biomass and community. A shift from diatom (Thalassiosira sp., Fragilariopsis sp.) to dinoflagellate (Protoperidinium sp.) community, along with the emergence of grazers was seen by the end of the observation period. The background environmental conditions also showed marked variations, as the concentration of nitrate at 0m depth reduced from 31.8 μM at Obs-1 to a non-detectable limit at Obs-3. Furthermore, at 0m depth, temperature increased from −1.32 °C at Obs-1 to −0.38 °C at Obs-3 while salinity decreased from 34.11 at Obs-1 to 33.68 at Obs-3, thus indicating the melting phase of sea ice from Obs-1 to Obs-3. These observations showed vertical stratification resulting from the basal melting of land-fast sea ice resulted in better availability of light, phytoplankton community change due to nutrient availability/utilization/limitation, followed by the presence of grazer community. This preliminary understanding will serve as a baseline dataset to design the targeted sampling/experiments in the future from the land-fast ice ecosystem.journal articl
Mesosiderite reheating history as deduced from merrillite and associated minerals
Full text linkThe 15th Symposium on Polar Science/Ordinary sessions [OA] Antarctic Meteorite, Thu. 5 Dec. / Entrance Hall (1st floor), National Institute of Polar Researchconference outpu