グリーンランドの氷床の上昇の変化は,主に雪の積もりの変動に起因する.
McConnell1, Arthern, Mosley-Thompson
1Desert Research Institute, University & Community College System of Nevada, Reno 89512, USA. jmcconn@dri.edu
Nature
|September 6, 2000
まとめ
グリーンランドの氷床の標高の変化は,1978年から1988年の間,雪の蓄積の変動によって引き起こされ,自然気候の変動を超えなかった. 氷床の上昇と雪の蓄積の長期的なモニタリングは,質量の変化を理解するために不可欠です.
科学分野:
- 氷河学 氷河学とは
- 気候科学 気候科学
- 地球システム科学 地球システム科学
背景:
- 気候変動に対する氷床の反応は,将来の海面上昇に大きく影響を与えます.
- 衛星データは,グリーンランドの氷床の標高の空間的変動を明らかにしているが,地質物理学的プロセスは不明のままである.
- 氷床の最近の変化と自然の変化を区別することが不可欠です.
研究 の 目的:
- 1978-88年の間,グリーンランドの南部の氷床の標高の変化を測定するために.
- 観測された標高変化に起因する地球物理学的プロセスを特定する.
- 最近の変化がグリーンランドの自然気候の変動に該当するかどうかを評価する.
主な方法:
- 物理的モデルをベースにした火山の密集化モデルを使用した.
- 12つの高地の氷芯から得られたデータを用いて,年間積雪量を再構築した.
- モデル化された標高の変化を,同時期の衛星測定値と比較した.
主要な成果:
- モデル化された蓄積による高層の変化は,1978-88年の衛星観測と密接に一致しました.
- 観測された標高の変化は,積雪の変動に起因している.
- より長い氷芯の分析は,グリーンランド氷床の自然な境界内の典型的な変動を示した.
結論:
- 積雪の変動性は,1978年から1988年の10年間におけるグリーンランドの氷床の上昇の変化の主な要因でした.
- 観測された変化は,氷床の長期的な自然な変動性の中にありました.
- 総合的な質量バランス評価のために,氷床の表面の上昇と雪の蓄積の統合された長期測定が必要である.
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