In order to provide the useful information for designing a wind turbine system in the area of cold Katabatic in , analyzed were the wind data acquired at the 10m level during the course of operation for five years from 1987 to 1991 by Japan Meteorological Agency and National Institute of Polar Research, and measured continuously for the certain periods of hours in 1991 by the anemometer on top of the 6m tower next to the small wind turbine system at Asuka Observation Camp in Antarctica. Several findings were drawn based on the analysis of data. The duration time of the wind velocity specifically more than 10m/s in the direction of ESE lasted extremely long throughout a year. Gust factors kept almost constant in the range over the velocity of 8m/s. Power spectra have a peak value at 0.052Hz and were well approximated by the equation expressed under the condition of the neutral stratification.

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Ammonium fractions from a soil of a penguin rookery in Antarctica and from water of a pond in the rookery exhibit the highest ¹⁵N/¹⁴N ratios among biogenic nitrogen so far observed. Though soils of seabird rookeries appear, in general, to have high nitrogen isotope ratios, the still higher ratios make the penguin rookery stand out from other seabird rookeries. The observation suggests that ammonia volatilization is a cause of the ¹⁵N enrichment in the soil ammonium and that the Antarctic climate is particularly effective on ¹⁵N enrichment for ammonium remained in the soil and water.

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1972年3月～1973年2月の1ケ年間, 越冬生活を送った第12次日本南極地域観測隊29名中13名いてBMR, FFAの季節変動は次の如く要約される。
1.冬季7月のBMRの低下, 秋季2月のBMRの亢進を除いて他の月にはBMRの変動は認められない。
2.冬季7月のBMRの低下は, 6月の暗夜の時期における生活が屋内生活が主となり, 身体活動の減少と室内気温18℃に曝露されていた為の影響と考えられる。
3.秋季2月のBMRの亢進は, 越冬終了直前の為, 身体活動が最も激しくなり, かつ, 0℃～-10℃の外気温に曝露された為の亢進と考えられる。
4.FFAの季節変動には著明な傾向を認めなかった。FFAの血中濃度は全期間を進じて平均816.7μEq/lと高いレベルにあった。
5.FFAとBMRの関係は, FFAの高い者はBMRが亢進の傾向にあるが, 個人内でのFFAとBMRの変動は有意な負の相関々係をとっている。即ち, BMRが亢進するとFFAは減少する。
6.BMRとRQの間には負の相関々係を示し, BMRが亢進するとRQは低下する。個人内での変動にも同様に負の相関々係がある。
7.FFAとRQの間には負の相関々係を有し, FFAの高い者はRQが低いという関係にあるが, FFAとRQの個人内での変動では有意の相関々係は認められなかった。

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In Antarctica, the geochemical properties of meltwater and pondwater are very sensitive to global warming. Therefore, understanding the geochemical properties of the meltwater and pondwater is crucial to evaluating global climate change. This study was performed to examine the chemical and isotopic compositions of the meltwater and pondwater at the Barton and Weaver Peninsulas of King George Island, Antarctica, to understand their spatial variation and to evaluate factors controlling the surface water chemistry. The meltwater, pondwater and seawater were sampled at 50 sites of the Barton and Weaver Peninsulas during the period from 23 December 2010 to 5 January 2011. The chemical compositions of the meltwater and pondwater were mainly influenced by sea salt. Additionally, the influence of water-rock interaction was observed in some meltwater and pondwater. The LREE/HREE ratios of some of the pondwater in the Barton Peninsula showed a decreasing trend by influence of water-rock interaction. The influences of sea salt and water-rock interaction were more dominant at the Barton Peninsula than the Weaver Peninsula. The δ¹⁸O and δD of the meltwater and pondwater showed a wide range. Little evaporation losses were observed at the Barton Peninsula but evaporation losses did not occurred at the Weaver Peninsula.

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For reconstructing past climate, an empirical linear relationship between air temperature and isotopic compositions of ice core has been used as a paleothermometer. However, the relationship between air temperature and stable isotope data is affected by the several factors other than temperature. Based on the result of Ichiyanagi et al. (2002), we examine the interannual variation of stable isotopes in precipitation at Argentine Island, Antarctica. The causes for the interannual variation of stable isotopes in Antarctic precipitation are discussed in the relation with El Niño/Southern Oscillation (ENSO) using large-scale atmospheric data. Anomalies of surface air temperature and δ¹⁸O of precipitation in the Antarctic Peninsula are negatively correlated with ENSO. The low (high) anomaly of δ¹⁸O is associated with southerly (northerly) and cold (warm) anomalies, which is considered to appear as a response to the ENSO teleconnection. Results of the water budget analysis considering the origin of water vapor, relative contribution and remaining ratio of moisture flux are very important for determining the observed δ¹⁸O in precipitation.

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Sea-level rise is a major effect of climate change. It has drawn international attention, because higher sea levels in the future would cause serious impacts in various parts of the world. There are questions associated with sea-level rise which science needs to answer. To what extent did climate change contribute to sea-level rise in the past? How much will global mean sea level increase in the future? How serious are the impacts of the anticipated sea-level rise likely to be, and can human society respond to them? This paper aims to answer these questions through a comprehensive review of the relevant literature. First, the present status of observed sea-level rise, analyses of its causes, and future projections are summarized. Then the impacts are examined along with other consequences of climate change, from both global and Japanese perspectives. Finally, responses to adverse impacts will be discussed in order to clarify the implications of the sea-level rise issue for human society.

(Communicated by Kiyoshi HORIKAWA, M.J.A.)

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This paper describes past climate and environmental changes during the past 101 to 105 year time scale obtained by recent studies on ice cores from Arctic and Antarctica. Shallow ice cores from Greenland and Svalbard show clear North Atlantic Oscillation (NAO) signals and explosive volcanic activities in the Northern Hemisphere and the equatorial regions. A deep ice core drilled to 2503 m at Dome Fuji, Antarctica covers the past 320 ka, which includes 3 glacial-interglacial cycles with Milankovitch cycles of about 20, 40, and 100 ka. Major chemical compositions and microparticle flux show high concentrations in glacials and low concentrations in interglain high-middle latitudes during glacial-interglacial cycles. The Dome Fuji deep ice core contains 25 visible tephra layers. An analysis of the chemical compositions shows the possible source volcanoes in and around the Antarctica.

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地球規模での気候変動は，様々な地域の野生生物に対し直接的または間接的に大きな影響を与えていることが知られている．ペンギンをはじめとする海鳥は，繁殖を行う陸地において，また採食を行う海洋において，気候変動の影響を受けると考えられ，生態系変化の指標種としてその個体数動向や生態変化がモニタリングされている．本論文では，気候変動がペンギン類に与える影響について，その生態的プロセスや将来予測に関する研究をレビューした．気候変動は，繁殖環境や採食環境の変化を通じて，現生のペンギン類18種のうち，13種に影響を与えており，ペンギンの個体数変化に影響する重要な要因となっていた．一方，その影響は複雑であり，同種内でも異なる地域間で，また同一個体群の中でも生活史パラメータ間で，正と負が逆の影響を与える場合があった．ペンギンの個体数変化の将来予測について，南極および亜南極域のペンギンで温暖化の進行の程度に合わせた精緻なシミュレーションが行われ，温暖化対策の重要性を示す結果が得られているものの，結果を解釈する上ではシミュレーションの不確実性についても考慮する必要があることを指摘した．また，気候変動がペンギンに影響を与えるプロセスをより正確に把握するために，採食行動の研究，とくにこれまでデータの少ない非繁殖期の成鳥や幼鳥の研究が今後必要であることを述べた．最後に，気候変動の影響下にあるペンギン個体群の復元力を高め保全を推進するためにも，ペンギン各種に対する人間活動の影響を可能な限り小さくすることが必要であることを論じた．

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