GRACE Measurements of Mass Variability in the Earth System

• DOI: 10.1126/science.1099192
• Publication Date: 2004-07-22T20:38:37Z
• Authors: Byron D. Tapley; Srinivas Bettadpur; John C. Ries; Paul F. Thompson; Michael M. Watkins
• Keywords: 550; 13. Climate action; 01 natural sciences; 620; 0105 earth and related environmental sciences

Monthly gravity field estimates made by the twin Gravity Recovery and Climate Experiment (GRACE) satellites have a geoid height accuracy of 2 to 3 millimeters at spatial resolution as small 400 kilometers. The annual cycle in variations, up 10 some regions, peaked predominantly spring fall seasons. Geoid variations observed over South America that can be largely attributed surface water groundwater changes show clear separation between large Amazon watershed smaller watersheds north. Such observations will help hydrologists connect processes traditional length scales (tens kilometers or less) those regional global scales.