21世紀初頭における地球規模の氷河の減量加速
Romain Hugonnet1,2,3, Robert McNabb4,5, Etienne Berthier6
1LEGOS, Université de Toulouse, CNES, CNRS, IRD, UPS, Toulouse, France. romain.hugonnet@gmail.com.
Nature
|April 29, 2021
まとめ
地球の氷河は急速に質量を失い 海面上昇に大きく貢献しています この研究は 気候変動の影響を理解するために 極めて重要な 氷河の質量損失の 異なる地域パターンを明らかにしています
科学分野:
- 氷河学
- 気候科学
- 地球システム科学
背景:
- 主要な氷床の外の氷河は急速に縮小し 水質学,海面,危険性に影響しています
- これまでの氷河の質量損失データは 稀で断片的であり 進化の理解を制限していました
研究 の 目的:
- 衛星時代における氷河の質量変化の 全球的な完全かつ一貫した見積もりを提供すること.
- 21世紀初頭における 氷河の大量減少の加速と対照的なパターンを明らかにするためです
主な方法:
- 地球上のすべての氷河の高空間時間解像度で地表の高さ変化をマッピングするために,大部分未使用の衛星アーカイブを使用しました.
- 独立した高精度測定で検証された推定値
主要な成果:
- 氷河は2000年から2019年の間に年間267 ± 16ギガトンの質量を失い,観測された海面上昇に21%貢献しました.
- 氷床の周辺では減量率が倍増した. 氷床の周辺では減量率が倍増した.
- 北大西洋での減速とアメリカ北西部の加速した損失を含む,対照的な地域の大量損失パターンを観測した.
結論:
- 氷河の質量減少は加速しており グリーンランドや南極の氷床を 単独で失っている量を超えています
- 氷河の変化の地域的変動を理解することは 将来の影響を予測し,水資源と海面上昇の緩和のための 適応政策を策定する上で 鍵となるものです
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