Developing a climate model with an ice-shelf component

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K12301
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 63010:Environmental dynamic analysis-related
• Research Institution: Japan Agency for Marine-Earth Science and Technology
• Principal Investigator: Kusahara Kazuya 国立研究開発法人海洋研究開発機構, 地球環境部門(環境変動予測研究センター), 研究員 (20707020)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: 南極棚氷底面融解 / 南大洋 / 海氷 / 南極沿岸水塊 / 海洋モデリング / 気候変動

Outline of Final Research Achievements

This research project aimed to incorporate an ice-shelf component into a global sea ice-ocean model, which has been used for climate modeling, and configured the models with horizontal resolutions of 1 degree and 0.25 degree. In order to compare and validate the modeling results of ice shelf-ocean interactions with observations in detail, we also prepared several configurations for East Antarctic regions and circumpolar Southern Ocean. During the five-year research period, we published a total of 15 original papers, 6 of which we were able to produce as the first author. The project has successfully incorporated ice-shelf component into a global sea-ice ocean model, paving the way for a direct representation of ice sheet/ice shelf-ocean interactions along the Antarctic coastal margins in a climate model.

Free Research Field

極域海洋学

Academic Significance and Societal Importance of the Research Achievements

各種設定において、南極沿岸域の3つの水塊（低温・高塩分の高密度陸棚水、高温・高塩分の周極深層水、高温・低塩の夏季表層水）の棚氷下への流入パターンの変化が、棚氷底面融解量を規定することを明らかにした。温暖化実験では、棚氷融解量が温暖化レベルに対して非線形応答することを見出した。さらに、全球1度全球モデルで2500年にわたる長期積分と仮想トレーサー実験を行い、南極沿岸の水塊の動態や海盆間の物質循環の時間スケールを見積もることに成功した。本課題による成果は、棚氷融解を数値モデルで直接表現できた点で学術的意義があり、また氷床変動を規定する棚氷変動の理解は海水準予測に貢献することから社会的意義も高い。