東南極の氷床の雪による増加は,近年の海面上昇を緩和している
Curt H Davis1, Yonghong Li, Joseph R McConnell
1Department of Electrical and Computer Engineering, University of Missouri-Columbia, Columbia, MO 65211, USA. davisch@missouri.edu
まとめ
東南極の氷床は,降水量の増加により,1992年から2003年にかけて著しい量を増し,世界の海面上昇を遅らせました.
科学分野:
- 氷河学 氷河学とは
- 気候科学 気候科学
- リモートセンシング (リモートセンサー)
背景:
- 南極の氷床の質量バランスは,世界の海面の変化を理解するために不可欠です.
- 以前の研究では,南極の氷の質量の傾向に関する異なる推定結果が得られた.
研究 の 目的:
- 東南極の氷床の質量変化を定量化するために.
- 観測された質量変化の要因を調査する.
- これらの変化が世界の海面に与える影響を評価する.
主な方法:
- 1992年から2003年にかけての衛星レーダー高度測定データ.
- 気象モデルによる降雪の推定値との比較.
主要な成果:
- 東南極の氷床の内部 (81.6°S北) は,年間45 ± 7億トンの氷を積んだ.
- この質量増加は,降水量の増加と関連しています.
- 観測された質量増加は,世界の海面上昇を0.12 ± 0.02 mm/年減らす可能性がある.
結論:
- 東南極の氷床の内部は,質量が蓄積されています.
- 降雪の増加は,この質量増加の主な要因である.
- この氷の質量の蓄積は,世界の海面上昇を部分的に相殺する.
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