2021/10/20 更新

写真a

アンドウ ユウタ
安藤 雄太
ANDO Yuta
所属
教育研究院 自然科学系 特任助教
理学部 特任助教
職名
特任助教
外部リンク

学位

  • 博士(学術) ( 2020年9月   三重大学 )

  • 修士(生物資源学) ( 2014年3月   三重大学 )

研究キーワード

  • 大気海洋相互作用

  • 渦相関法

  • 乱流フラックス

  • 黒潮

  • 北極海

  • 超音波風速計

  • 熱収支

  • CO2フラックス

  • 海面フラックス

  • 大気境界層

  • 北極振動

  • テレコネクション

研究分野

  • 自然科学一般 / 大気水圏科学  / 大気海洋相互作用

経歴(researchmap)

  • 新潟大学   理学部   特任助教

    2020年10月 - 現在

      詳細を見る

    国名:日本国

    researchmap

  • 三重大学   大学院生物資源学研究科   研究員

    2020年5月 - 現在

      詳細を見る

    国名:日本国

    researchmap

  • 鈴鹿工業高等専門学校   非常勤講師

    2016年4月 - 現在

      詳細を見る

    国名:日本国

    researchmap

  • 国立極地研究所   技術補佐員

    2014年8月 - 2016年3月

      詳細を見る

    国名:日本国

    researchmap

経歴

  • 新潟大学   理学部   特任助教

    2020年10月 - 現在

  • 新潟大学   教育研究院 自然科学系   特任助教

    2020年10月 - 現在

学歴

  • 三重大学大学院   生物資源学研究科   博士後期課程

    2014年4月 - 2020年5月

      詳細を見る

    国名: 日本国

    researchmap

  • 三重大学大学院   生物資源学研究科   博士前期課程

    2012年4月 - 2014年3月

      詳細を見る

    国名: 日本国

    researchmap

  • 三重大学   生物資源学部   学士課程

    2008年4月 - 2012年3月

      詳細を見る

    国名: 日本国

    researchmap

所属学協会

▶ 全件表示

 

論文

  • Warm hole in Pacific Arctic sea ice cover forced mid-latitude Northern Hemisphere cooling during winter 2017–18 査読

    Scientific Reports   9   5567   2019年4月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    In North America and Asia, extreme cold weather characterized the winter of 2017–18. At the same time, the Pacific, the Bering Sea, and the Atlantic Arctic regions experienced anomalously low sea ice extent in the early winter. The jet stream dividing cold Arctic air from warm air deviated from normal zonal patterns northward into the ice-free areas north of the Bering Strait. Large southward jet stream pathways formed over Asia and America, allowing cold air to spread into Asia and the southern areas of North America. We hypothesise that the late autumn Bering Strait sea-ice anomaly and Pacific atmospheric rivers were partially responsible for the cold winter. We used data analyses and numerical experiments to test this hypothesis. We propose a positive feedback mechanism between the sea ice anomaly and atmospheric river activity, with anomalous south winds toward the sea ice anomaly potentially leading to more warm water injected by the wind-driven current through the Bering Strait. Our findings suggest that Poleward propagation of the atmospheric rivers made upper air warm, leading to their upgliding, which further heated the overlying air, causing poleward jet meanders. As a part of this response the jet stream meandered southward over Asia and North America, resulting in cold intrusions. We speculate that the positive feedback mechanism observed during the 2017–18 winter could recur in future years when the sea-ice reduction in the Pacific Arctic interacts with enhanced atmospheric river activity.

    DOI: 10.1038/s41598-019-41682-4

    researchmap

  • Detection of a climatological short break in the polar night jet in early winter and its relation to cooling over Siberia 査読

    Yuta Ando, Koji Yamazaki, Yoshihiro Tachibana, Masayo Ogi, Jinro Ukita

    ATMOSPHERIC CHEMISTRY AND PHYSICS   18 ( 17 )   12639 - 12661   2018年8月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:COPERNICUS GESELLSCHAFT MBH  

    The polar night jet (PNJ) is a strong stratospheric westerly circumpolar wind at around 65 degrees N in winter, and the strength of the climatological PNJ is widely recognized to increase from October through late December. Remarkably, the climatological PNJ temporarily stops increasing during late November. We examined this "short break" in terms of the atmospheric dynamical balance and the climatological seasonal march. We found that it results from an increase in the upward propagation of climatological planetary waves from the troposphere to the stratosphere in late November, which coincides with a maximum of the climatological Eliassen-Palm (EP) flux convergence in the lower stratosphere. The upward propagation of planetary waves at 100 hPa, which is strongest over Siberia, is related to the climatological strengthening of the tropospheric trough over Siberia. We suggest that longitudinally asymmetric forcing by land-sea heating contrasts caused by their different heat capacities can account for the strengthening of the trough.

    DOI: 10.5194/acp-18-12639-2018

    Web of Science

    researchmap

  • Synchrony of trend shifts in Sahel boreal summer rainfall and global oceanic evaporation, 1950-2012 査読

    Alima Diawara, Yoshihiro Tachibana, Kazuhiro Oshima, Hatsumi Nishikawa, Yuta Ando

    HYDROLOGY AND EARTH SYSTEM SCIENCES   20 ( 9 )   3789 - 3798   2016年9月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:COPERNICUS GESELLSCHAFT MBH  

    Between 1950 and 2012, boreal summer (rainy season) rainfall in the Sahel changed from a multi-decadal decreasing trend to an increasing trend (positive trend shift) in the mid-1980s. We found that this trend shift was synchronous with similar trend shifts in global oceanic evaporation and in land precipitation on all continents except the Americas. The trend shift in oceanic evaporation occurred mainly in the Southern Hemisphere (SH) and the subtropical oceans of the Northern Hemisphere (NH). Because increased oceanic evaporation strengthens the atmospheric moisture transport toward land areas, the synchrony of oceanic evaporation and land precipitation is reasonable. Surface scalar winds over the SH oceans also displayed a positive trend shift. Sea surface temperature (SST) displayed a trend shift in the mid-1980s that was negative (increasing, then decreasing) in the SH and positive in the NH. Although SST had opposite trend shifts in both hemispheres, the trend shift in evaporation was positive in both hemispheres. We infer that because strong winds promote evaporative cooling, the trend shift in SH winds strengthened the trend shifts in both SST and evaporation in the SH. Because high SST promotes evaporation, the trend shift in NH SST strengthened the NH trend shift in evaporation. Thus differing oceanic roles in the SH and NH generated the positive trend shift in evaporation; however, the details of moisture transport toward the Sahel are still unclear, or perhaps there is no single determining influence.

    DOI: 10.5194/hess-20-3789-2016

    Web of Science

    researchmap

  • Abnormal Winter Weather in Japan during 2012 Controlled by Large-Scale Atmospheric and Small-Scale Oceanic Phenomena 査読

    Yuta Ando, Masayo Ogi, Yoshihiro Tachibana

    MONTHLY WEATHER REVIEW   143 ( 1 )   54 - 63   2015年1月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER METEOROLOGICAL SOC  

    Negative Arctic Oscillation (AO) and western Pacific (WP) indices persisted from October to December 2012 in the Northern Hemisphere. For the first time, the monthly AO and WP were both negative for three consecutive months since records have been kept. Although in general negative AO and WP phases cause Siberia, East Asia, and Japan to be abnormally cold, Japan was relatively warm in October 2012 even though both the AO and WP were strongly negative. The temperature of the Sea of Japan reached a record-breaking high in October 2012, and it was found that heating by these very warm waters, despite the small size of the Sea of Japan, overwhelmed the cooling effect of the strongly negative AO and WP in October. Linear regression analyses showed that Japan tends to be warm in years when the Sea of Japan is warm. Consequently, the temperature over Japan is controlled by interannual variations of small-scale oceanic phenomena as well as by large-scale atmospheric patterns. Previous studies have ignored such small-scale oceanic influences on island temperatures.

    DOI: 10.1175/MWR-D-14-00032.1

    Web of Science

    researchmap

  • Abnormal winter weather in Japan during 2012 controlled by large-scale atmospheric and small-scale oceanic phenomena

    Yuta Ando, Masayo Ogi, Yoshihiro Tachibana

    Monthly Weather Review   143 ( 1 )   54 - 63   2015年

     詳細を見る

    記述言語:英語   掲載種別:学位論文(修士)   出版者・発行元:American Meteorological Society  

    NegativeArcticOscillation (AO) andwestern Pacific (WP) indices persisted fromOctober toDecember 2012 in the Northern Hemisphere. For the first time, the monthly AO and WP were both negative for three consecutive months since records have been kept. Although in general negative AO andWP phases cause Siberia, East Asia, and Japan to be abnormally cold, Japan was relatively warm in October 2012 even though both the AO and WP were strongly negative. The temperature of the Sea of Japan reached a record-breaking high in October 2012, and itwas found that heating by these verywarmwaters, despite the small size of the Sea of Japan, overwhelmed the cooling effect of the strongly negative AO and WP in October. Linear regression analyses showed that Japan tends to bewarmin yearswhen the Sea of Japan iswarm.Consequently, the temperature over Japan is controlled by interannual variations of small-scale oceanic phenomena as well as by large-scale atmospheric patterns. Previous studies have ignored such small-scale oceanic influences on island temperatures.

    DOI: 10.1175/MWR-D-14-00032.1

    Scopus

    researchmap

  • 実用的条件下での渦相関法とバルク法による海面乱流フラックスの比較 査読

    安藤 雄太, 立花 義裕, 根田 昌典, 内田 誠, 前川 陽一, 中村 亨, 仲里 慧子

    海と空   89 ( 1 )   1 - 8   2013年7月

     詳細を見る

    記述言語:日本語   掲載種別:研究論文(学術雑誌)  

    乱流フラックスは大気海洋相互作用の素過程を理解する上で重要な要素である.本研究では,三重大学練習船「勢水丸」に常設された渦相関観測システムを用いて,外洋と内洋の境界である伊良湖水道を連続的に観測したデータを初めて解析した.厳密な条件下ではなく,実用的な船舶上での条件下での比較を行うことで,制約が少なくより多くの観測データを解析対象とすることが可能である.このデータを元に,渦相関法とバルク法(COARE3.0)で計算した乱流顕熱フラックスの違いに着目し,その差を生む原因を明らかにすることを研究目的とする.結果,変動は似ていたが,バルク法が渦相関法より大きな値を示し,その差は①風速依存性がある,②温度差依存性があることが考えられる.したがって,本研究で示された風速・大気安定度依存性のある渦相関法とバルク法の差は,風速・大気安定度依存性のあるバルク係数を改良することで,その差を小さくできる可能性があることが示唆された.

    researchmap

▶ 全件表示

MISC

講演・口頭発表等

▶ 全件表示

 

担当経験のある授業科目(researchmap)

  • 現代科学Ⅳ

    2016年4月
    -
    現在
    機関名:鈴鹿工業高等専門学校

     詳細を見る