2026-06-29 総合研究大学院大学
南極大陸上空を川のように流れる水蒸気「大気の川」の模式図。大気の川は南極大陸上に極端な降雪をもたらす現象として注目されており、本研究ではその三次元構造を捉え、南極の降水に及ぼす影響を評価しました。
＜関連情報＞
- https://www.soken.ac.jp/news/2026/20260629_1.html
- https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2025GL120986
3D大気河川アルゴリズムを用いた南極の降水量の捉え方 Capturing Antarctic Precipitation With a 3D Atmospheric River Algorithm
K. Takahashi, J. Inoue, K. Sato, N. Hirasawa, K. Yamada
Geophysical Research Letters Published: 05 May 2026
DOI:https://doi.org/10.1029/2025GL120986
Abstract
Atmospheric rivers (ARs) typically lead to intense precipitation and play an essential role in the Antarctic ice surface mass balance. Their detection in the Antarctic region is challenging, preventing consistent evaluation of their role at a global scale. In this study, we extended a conventional method and developed a new three-dimensional AR detection algorithm, which we applied over Antarctica. The results showed that the detected ARs at Dome Fuji during the 44th Japanese Antarctic Research Expedition were associated with more than half of the significant precipitation events and contributed to approximately 40% of the total precipitation. Climatologically, from 1979 to 2023, the ARs occurred less than 10% of the time but contributed to 30%–60% of the annual total precipitation. Furthermore, AR-related precipitation effectively captured the regional variability of long-term trends in Antarctic precipitation, indicating that ARs exert substantial control over Antarctic precipitation variability.
