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地球系における質量変動のGRACE測定結果
Byron D Tapley1, Srinivas Bettadpur, John C Ries
1Center for Space Research, University of Texas, Austin, TX 78712, USA.
Science (New York, N.Y.)
|July 27, 2004
まとめ
グラビティ・リカバリー・アンド・気候実験 (GRACE) 衛星は,正確な毎月のジオイド高度測定を提供します. これらの観測は,南米における季節的な水質変化を明らかにし,水文学的研究を支援しています.
科学分野:
- ジオデシ (Geodesy) とは
- 水文学 水文学とは
- 気候科学 気候科学
背景:
- 双子のGravity Recovery and Climate Experiment (GRACE) 衛星は,毎月重力場の推定値を提供している.
- これらの推定は,400キロメートルの空間解像度で高ジオイド高精度 (2-3ミリメートル) を達成します.
研究 の 目的:
- 年間ジオイドの変動と水文学的プロセスとの相関を分析する.
- アマゾン流域と隣接する小さな流域の間の水文信号を区別するために.
主な方法:
- GRACE衛星からの毎月の重力場データを活用したものです.
- ジオイドの高さの変動とその季節的パターンを分析する.
- 南米の異なる流域の水文信号を比較する.
主要な成果:
- 観測された年間ジオイドの変動は最大10ミリメートルで,春と秋にピークに達します.
- 南米における重要なジオイドの変動は,地表と地下水の変化に起因している.
- アマゾンと北部の流域の間の水文学的信号の明確な区別を示した.
結論:
- GRACEの衛星データは,大規模な水文学的変化を効果的に捉えています.
- この発見により,地元の水文学的過程を地域的およびグローバルなスケールに結びつけることができます.
- この研究は,南米における水質の動態に関する我々の理解を深める.
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