Strong ice-ocean interaction beneath Shirase Glacier Tongue in East Antarctica

Mass loss from the Antarctic ice sheet, Earth’s largest freshwater reservoir, results directly in global sea-level rise and Southern Ocean freshening. Observational and modeling studies have demonstrated that ice shelf basal melting, resulting from the inflow of warm water onto the Antarctic continental shelf, plays a key role in the ice sheet’s mass balance. In recent decades, warm ocean-cryosphere interaction in the Amundsen and Bellingshausen seas has received a great deal of attention. However, except for Totten Ice Shelf, East Antarctic ice shelves typically have cold ice cavities with low basal melt rates. Here we present direct observational evidence of high basal melt rates (7–16 m yr−1) beneath an East Antarctic ice shelf, Shirase Glacier Tongue, driven by southward-flowing warm water guided by a deep continuous trough extending to the continental slope. The strength of the alongshore wind controls the thickness of the inflowing warm water layer and the rate of basal melting

Water properties, heat and volume fluxes of Pacific water in Barrow Canyon during summer 2010

AbstractOver the past few decades, sea ice retreat during summer has been enhanced in the Pacific sector of the Arctic basin, likely due in part to increasing summertime heat flux of Pacific-origin water from the Bering Strait. Barrow Canyon, in the northeast Chukchi Sea, is a major conduit through which the Pacific-origin water enters the Arctic basin. This paper presents results from 6 repeat high-resolution shipboard hydrographic/velocity sections occupied across Barrow Canyon in summer 2010. The different Pacific water masses feeding the canyon – Alaskan coastal water (ACW), summer Bering Sea water (BSW), and Pacific winter water (PWW) – all displayed significant intra-seasonal variability. Net volume transports through the canyon were between 0.96 and 1.70Sv poleward, consisting of 0.41–0.98Sv of warm Pacific water (ACW and BSW) and 0.28–0.65Sv of PWW. The poleward heat flux also varied strongly, ranging from 8.56TW to 24.56TW, mainly due to the change in temperature of the warm Pacific water. Using supplemental mooring data from the core of the warm water, along with wind data from the Pt. Barrow weather station, we derive and assess a proxy for estimating heat flux in the canyon for the summer time period, which is when most of the heat passes northward towards the basin. The average heat flux for 2010 was estimated to be 3.34TW, which is as large as the previous record maximum in 2007. This amount of heat could melt 315,000km2 of 1-meter thick ice, which likely contributed to significant summer sea ice retreat in the Pacific sector of the Arctic Ocean

ニホン ナンキョク チイキ カンソクタイ ノ カキ コウドウチュウ ニオケル カイヒョウ ブンプ ジョウホウ ノ テイキョウ システム

最新の高分解能のAdvanced Microwave Scanning Radiometer-EOS (AMSR-E) 海氷密接度データを南極地域観測隊に提供するシステムを開発した.このシステムによって,デジタルデータとしての海氷分布情報が1-2日程度の遅れで第51次及び第52次日本南極地域観測隊に送られ,係留系設置作業に関わる現地判断に役立てることができた.さらに,このデータは東京海洋大学「海鷹丸」や海洋研究開発機構「白鳳丸」等の南極海氷域周辺を航行する他の日本の観測船にも提供され,それぞれの船の運航上の参考情報として役立てられた.We developed a system to supply Advanced Microwave Scanning Radiometer-EOS (AMSR-E) sea ice concentration data to the Japanese Antarctic Research Expedition (JARE). Using this system, digital sea ice concentration data were provided to JARE-51 and -52 on the icebreaker Shirase, with a lag time of 1-2 days. The sea ice data were highly useful during the deployment of the moorings. The system was also utilized by other Japanese research vessels in the Southern Ocean, and the sea ice data were helpful for the operation of the vessels

Observations of frazil ice formation and sediment upward transport off Barrow in the Chukchi Sea

第6回極域科学シンポジウム[OM] 極域気水圏11月16日（月）　統計数理研究所 セミナー室2（D304

Mooring measurement of sea ice and ocean in the Cape Darnley Polynya, Antarctica

第2回極域科学シンポジウム/第34回気水圏シンポジウム 11月17日（木） 統計数理研究所 セミナー室

Interannual variability of sea ice production in a hybrid latent and sensible heat coastal polynya off Barrow

第6回極域科学シンポジウム分野横断セッション：[IA] 急変する北極気候システム及びその全球的な影響の総合的解明―GRENE北極気候変動研究事業研究成果報告2015―11月19日（木）　国立極地研究所１階交流アトリウ

Sea ice thickness measurements with electro-magnetic inductive sounder in the pack ice zone off Syowa Station

第3回極域科学シンポジウム/第35回極域気水圏シンポジウム 11月29日（木） 国立国語研究所 ２階多目的

Measurements of snow depth and sea ice thickness by electromagnetic-induction measurements observed by Japan and Australia in the Antarctic Ocean.

第2回極域科学シンポジウム/第34回気水圏シンポジウム 11月17日（木） 統計数理研究所 セミナー室