ダイ44ジ ナンキョク チイキ カンソクタイ カキ コウドウ ホウコク 2002-2003

第44次南極地域観測隊は,鮎川勝観測隊長以下60名(うち越冬隊は小島秀康副隊長兼越冬隊長ら40名)で構成された.越冬隊のうち8名(大日方一夫副隊長兼越冬副隊長ら)はドームふじ観測拠点で越冬し,夏隊のうち3名(小達恒夫副隊長(専用観測船担当)ら)は「専用観測船」で行動した.このほか,越冬隊に4名,夏隊に6名および専用観測船に16名が,同行者として観測隊と行動を共にした.2002年11月14日,南極観測船「しらせ」は東京港晴海ふ頭より出発した.観測隊57名およびその同行者10名(NHK放送記念事業など報道関係者9名,研究者1名)は,11月28日に成田から空路でオーストラリアのシドニー経由パースに向かい,29日にフリーマントルで「しらせ」に乗船した.「しらせ」は,12月3日に同港を発ち,15日にリュツォホルム湾沖に到着し,26日に昭和基地に接岸した.2002年12月17日から2003年2月15日までの間に,昭和基地および見返り台(S16: ドームふじ観測拠点)への物資輸送,昭和基地からの廃棄物の積み込み,同基地における観測および建設作業,内陸および沿岸地域における野外観測などを行った.昭和基地等への物資輸送量は1225トンであった.昭和基地から「しらせ」に積載した廃棄物量は162トン,持ち帰り一般物資は139トンであった.昭和基地における夏期設営作業では,観測系のPPB飛実験支援のほか,見晴らし燃料タンク-昭和基地間の燃料送油管の設置第2年次工事,インテルサットアンテナの基礎コンクリート打設工事,300kVA発電機1号機のオーバーホール,基地側燃料タンクの防油堤建設工事,放送事業用の直径4.8mパラボラアンテナ放送棟小型発電機小屋の建設とその内部設備送配電線工事等36項目にわたった.夏期観測では,昭和基地における観測として4機の南極周回気球飛実験を実施したほか,野外における観測として宗谷海岸露岩域一帯から,明るい岬などのプリンスオラフ海岸露岩域に至る地学地質,陸上生物,測地,広帯域地震計観測などを実施した.また,気水圏系では,氷河末端域の消耗量観測およびパッダ沖多年氷の採取を行ったほか,内陸ドーム旅行中には雪氷学的調査を実施した.2003年2月14日までに第43次越冬隊員および第44次夏隊の野外調査隊,基地の設営作業者等を順次「しらせ」に収容し,2月15日の最終便の後に「しらせ」は北上を開始した.2月22日から26日にかけてアムンゼン湾沖で海底地形測量を実施した.「しらせ」による停船航走観測は,往復路ともほぼ計画通りの観測を実施した.「しらせ」は,3月21日にシドニーに入港し,27日に同港を発ち4月13日に東京港に帰港した.観測隊は3月29日に空路成田に帰国した.他方,「専用観測船」は,2003年2月17日にニュージーランドのウェリントンを出港し,東経140度付近の南極海で約10日間の海洋観測を行い,3月13日に同港に帰った.観測隊員等は3月17日に空路成田に帰国した.The summer activities of the 44th Japanese Antarctic Research Expedition (JARE-44) in 2002-2003 on board the Antarctic research vessel Shirase and at and around Syowa Station, Antarctica are reported. JARE-44 members on board the Shirase included forty members of the wintering party and seventeen members of the summer party. The summer party and wintering party were accompanied by six other persons (five journalists and one geologist) and four other persons (journalists), respectively. The Shirase left Tokyo on 14 November 2002 and arrived at Fremantle, Western Australia on 28 November. JARE-44 left Tokyo on 28 November by airplane, and boarded the Shirase at Fremantle on 29 November. The ship reached the pack ice edge near Lutzow-Holm Bay on 15 December and anchored at Syowa Station on 26 December. The unloading of 1225 tons of cargo by helicopters and surface vehicles was completed by 17 January 2003. Then the ship loaded 162 tons of waste from Syowa Station between 3 January and 10 February. After the completion of construction and field work in the Syowa Station area, the JARE-44 summer party and JARE-43 wintering party on board the Shirase left Syowa Station on 15 February. The members of the summer party and JARE-43 wintering party returned to Narita via Sydney on 29 March. The Shirase returned to Tokyo on 13 April. The following scientific activities were carried out during summer operations of JARE-44: a) geological and geodetic surveys, biological, glaciological, geophysical, oceanographic and geomagnetic observations along the Soya Kaigan and Kronprins Olav Kyst, b) geophysical observations of the aurora australis using a Polar Patrol Balloon at Syowa Station, c) topographical survey of the seabed at north waters near area of Amundsen Bay on board the Shirase, d) meteorological, marine biological, oceanographic, atmospheric and geomagnetic observations and gravity measurements on board the Shirase

ナンキョク ショウワキチ タテモノ ノ モクシツヘキ パネル ワクザイ ノ ザンゾン キョウド チョウサ

南極昭和基地で現在使用されている建物の木質壁パネル枠材の残存強度をビスの引抜き試験によって調査した.強度の基準値(初期値)は,昭和基地で調査した枠材とほぼ同じ気乾密度の新材について強度と気乾密度の関係を求めた実験報告(平居ら,南極資料,46,481,2002)を参照して推定した.残存強度は建物建設後の経過年数に伴って徐々に低下している.また,外壁が直面する方角による残存強度の違いはほとんど見られなかった.更に,今回の調査で用いたビスの引抜き試験から枠材の強度特性を推定した.その結果,構造部材の劣化速度は緩やかであり,現在昭和基地で使用されている建物は設計で要求される構造性能をまだ十分に保持していることが確かめられた.The remaining strength of frame material in wooden wall panels of buildings being used now at Syowa Station in Antarctica was measured by wood screw pulling out tests. An initial value of pulling strength of wood screws was assumed referring to the test report by Hirai et al. (Nankyoku Shiryo, 46, 481, 2002). In that report, the relation between the strength of new wood and air-dried density of the material was presented. The air-dried density is almost the same as what in the frame material measured at Syowa Station. The strength has decreased gradually with the years after the construction of buildings. The remaining strength was roughly independent of facing direction of outside wall panels of buildings. Moreover, the mechanical properties of the frame material were assumed from the result of the wood screw pulling out test. Since the deterioration speed of structural properties has been very gradual, the wooden wall panels of buildings used now at Syowa Station are confirmed to maintain the structural performance required by the structural design

ナンキョク カンソクタイ ソウビ ウェア ノ ケンキュウ カイハツ

南極地域観測隊員が着装しているウェアを改善するために,観測隊員に聞き取り調査を行った.その結果,極地では動作の種類が多く,作業性を高めるには,「ゆとり量」が一般の衣料に比べ必要であった.また,設営などの作業では,一時的に体温の上昇があることから,汗や顔の周りの霜の対策が重要であることなどを考慮し,開発ウェアには,ポリエステル,ナイロン等の化学繊維(糸)に各種機能(透湿防水,保温,帯電防止など)を付与し,加工した機能性繊維を使用し,透湿・防水・帯電防止・保温性を高めた.また,被服構成(パターン)も考慮した.デザインコンセプトは,「南極観測隊員は,研究者と研究を支えるスタッフ」ということを観察者に示し,「機能性に優れた,知的でスタイルをよくみせるウェア」の研究開発を試みた.The design of wear for Japanese Antarctic Research Expedition (JARE) members was investigated. Wear must be loose-fitting because JARE members perform may kinds of operations. Heat must be able to escape easily. Considering that measures to deal with sweat and frost are necessary, synthetic fibers such as polyester and nylon wear used and treated to increase breathablity, water resistance, resistance to static electricity, and thermal insulation. We produced wear appropriate for JARE members including researchers and research support staff, who need clothing that is both highly functional and in a style appropriate for intellectual pursuits

シラセ サイヒョウ コウコウ データ ガ シメス ナンキョク リュツォ・ホルムワン テイチャクヒョウ ノ ネンネン ヘンカ

南極リュツォ・ホルム湾において毎年ほぼ同時期,同海域を航海する砕氷船「しらせ」は,海氷モニタリング・プラットフォームに適している.同湾の海氷状況の年々変化を推測するために,1983年から2002年までの間の「しらせ」砕氷航行データを解析した.主にラミング砕氷と氷厚や積雪深との関係を調べ,ラミング一回当たりの進出距離を砕氷航行の難易度の指標とすることにより,定着氷域の変化の特徴を抽出した.ラミング時の進出距離が短い1990年代前・中期は,航海が困難で厳しい氷状を反映し,氷厚や積雪深が大きい.一方,1990年代終わりから2002年までの間は,進出距離が長い傾向にあり,湾内定着氷の崩壊・流出の頻発期とも符合していることがわかった.Characteristics of sea-ice conditions in Lutzow-Holmbukta, Antarctica, have been investigated using the ice navigation log from the icebreaker Shirase, which has made a voyage almost at the same season and in the same sailing route every year since 1983. The vessel is considered as a suitable monitoring platform for sea ice. Not only basic information such as ice thickness and snow depth, but also ramming icebreaking data have been analyzed. In particular, the penetrating distances by ramming reflect difficulty in ice navigation and show distinctly interannual variations from 1983 to 2002. The periods with longer distances are consistent with those when breakup of landfast ice occurred frequently in the bay. The penetrating distances have shown a tendency to increase since the end of the 1990s, when ice breakup has been pronounced

ショウワキチ カンリトウ ゴリュウイキ タテモノ シュウヘン ノ フキダマリ カンソク ト ジンコウユキ ヲ モチイタ フウドウ モケイ ジッケン

2002年2月から11月にかけて,昭和基地主要部の管理棟後流域にある倉庫棟及び汚水処理棟周辺に発生した吹きだまりの観測を行った.併せて昭和基地主要部の建物近傍2点で風向・風速を観測し,地上高度0.5 mの吹雪フラックスを計測した.これらの観測データをもとに,吹雪フラックスに対応した吹きだまりの堆積状況を明らかにし,ブリザードの主風向変動が建物周囲の吹きだまり形成に与える影響をまとめた.更に昭和基地主要部周辺を1/100模型によってモデル化した人工雪風洞実験を行って吹きだまり発生状況の再現を試み,その発生と成長の機構を考察した.A snow drift survey around buildings in the wake of the central building of Syowa Station was carried out from February to November 2002. Wind was measured at two points above the roofs of buildings simultaneously. Measurement of mass flux of snow 0.5 m alone the ground was carried out in an undisturbed spot away from the main part of Syowa Station. Studying these observation data, it was found that the relation between the mass flux of snow and the volume of snow deposition around buildings can be expressed simply in a linear equation. And it was confirmed that the form of snow drift was sensitive to the properties of wind. The wind tunnel test was performed with a 1/100 scale model of the main part of Syowa Station. The blowing snow was modeled with artificial snow in a wind tunnel. The growth of snow deposition around the building models was measured at regular intervals. Variations of the shape of snow drift were observed in the wake especially. In comparison with the snow drift survey at Syowa Station, similarity of snow deposition on the wake of the obstacles was confirmed. The wind tunnel test with artificial snow was useful as a supplement to the field observations

ショウワキチ カンソクトウ デ 35 ネンカン シヨウ シタ コウゾウ ガスケット ノ カタサ チョウサ

第43次日本南極地域観測隊越冬隊において,昭和基地の観測棟で35 年間使用された構造ガスケットの硬さ試験を行った.新品の構造ガスケットを用いて硬さ試験を行い,その結果を初期値とした.紫外線が多く当たる北西面の構造ガスケットは,南東面の構造ガスケットに比べて劣化が進んでいた.屋外側と屋内側の劣化の程度は,ほぼ同じであった.観測棟で35 年間使用した構造ガスケットは,新品の構造ガスケットに比べて,硬さが1 割増加した程度であり,大きな亀裂などは見られなかった.これらより,この構造ガスケットは今後も昭和基地で継続して使用可能であると考えられる.A structural gasket at the observation hut in Syowa Station has been in use for 35 years. We studied the hardness of the original structural gasket during the 43rd Japanese Antarctic Research Expedition. We tested that of the new article, and the results are assumed to be an initial value. The structural gasket at the northwest section of the station deteriorated to a greater extent than did the structural gasket at the southeast section, because of the former\u27s exposure to ultraviolet radiation. The exterior and interior components of the northwest structural gasket show similar degrees of degradation. This structural gasket has hardened by 10 % relative to the new structural gasket. The 35-year-old structural gasket contains no large cracks, indicating its suitability for continual use

Polar cusp, plasma mantle particles and their relationships to polar rain

On the basis of low altitude DMSP satellite particle data, characteristics of polar rain, cusp and plasma mantle are examined during the asymmetric polar rain enhancement period. Obtained results are summarized as follows : (1) From the comparison between number flux of cusp and polar rain precipitations, the cusp flux does not increase correlatively with the increasing of polar rain flux. This result suggests that sources of precipitating particles are quite different from each other. (2) Low energy pulsive electrons (plasma mantle) are occasionally observed in the polar rain region. These plasma mantle particles are observed in both hemispheres and the polar rain enhancement shows hemispheric asymmetry. The mixing of polar rain and plasma mantle may be occurred due to the movement of plasma mantle by electric field drift

Activities of the summer party of the 44th Japanese Antarctic Research Expedition, Marine Science Cruise 2003

The summer activities of the 44th Japanese Antarctic Research Expedition (JARE-44) in 2002-2003 on board the Antarctic research vessel Shirase and at and around Syowa Station, Antarctica are reported. JARE-44 members on board the Shirase included forty members of the wintering party and seventeen members of the summer party. The summer party and wintering party were accompanied by six other persons (five journalists and one geologist) and four other persons (journalists), respectively. The Shirase left Tokyo on 14 November 2002 and arrived at Fremantle, Western Australia on 28 November. JARE-44 left Tokyo on 28 November by airplane, and boarded the Shirase at Fremantle on 29 November. The ship reached the pack ice edge near Lutzow-Holm Bay on 15 December and anchored at Syowa Station on 26 December. The unloading of 1225 tons of cargo by helicopters and surface vehicles was completed by 17 January 2003. Then the ship loaded 162 tons of waste from Syowa Station between 3 January and 10 February. After the completion of construction and field work in the Syowa Station area, the JARE-44 summer party and JARE-43 wintering party on board the Shirase left Syowa Station on 15 February. The members of the summer party and JARE-43 wintering party returned to Narita via Sydney on 29 March. The Shirase returned to Tokyo on 13 April. The following scientific activities were carried out during summer operations of JARE-44: a) geological and geodetic surveys, biological, glaciological, geophysical, oceanographic and geomagnetic observations along the Soya Kaigan and Kronprins Olav Kyst, b) geophysical observations of the aurora australis using a Polar Patrol Balloon at Syowa Station, c) topographical survey of the seabed at north waters near area of Amundsen Bay on board the Shirase, d) meteorological, marine biological, oceanographic, atmospheric and geomagnetic observations and gravity measurements on board the Shirase