Print Email Facebook Twitter Assessing Global Present-Day Surface Mass Transport and Glacial Isostatic Adjustment From Inversion of Geodetic Observations Title Assessing Global Present-Day Surface Mass Transport and Glacial Isostatic Adjustment From Inversion of Geodetic Observations Author Jiang, Yan (Geological Survey of Canada; University of Victoria) Wu, Xiaoping (California Institute of Technology) van den Broeke, Michiel R. (Universiteit Utrecht) Kuipers Munneke, Peter (Universiteit Utrecht) Simonsen, Sebastian B. (Technical University of Denmark) van der Wal, W. (TU Delft Physical and Space Geodesy; TU Delft Astrodynamics & Space Missions) Vermeersen, L.L.A. (TU Delft Physical and Space Geodesy; TU Delft Astrodynamics & Space Missions; NIOZ Royal Netherlands Institute for Sea Research) Date 2021 Abstract Long-term monitoring of global mass transport within the Earth system improves our ability to mitigate natural hazards and better understand their relations to climate change. Satellite gravity is widely used to monitor surface mass variations for its unprecedented spatial and temporal coverage. However, the gravity data contain signals from visco-elastic deformation in response to past ice sheet melting, preventing us from extracting signals of present-day surface mass trend (PDMT) directly. Here we present a global inversion scheme that separates PDMT and visco-elastic glacial isostatic adjustment (GIA) signatures by combining satellite gravimetry with satellite altimetry and ground observations. Our inversion provides global dual data coverage that enables a robust separation of PDMT and GIA spherical harmonic coefficients. It has the advantage of providing estimates of Earth's long wavelength deformation signatures and their uncertainties. Our GIA result, along with its uncertainty estimates, can be used in future GRACE processing to better assess the impact of GIA on surface mass change. Our GIA estimates include a rapid GIA uplift in the Southeast Alaska and the Amundsen Sea Embayment, due to the visco-elastic response to recent glacial unloading. We estimate the average surface mass change rate from 2002–2010 to be −203 ± 3 GT·a−1 in Greenland, −126 ± 18 GT·a−1 in Antarctica and, −62 ± 5 GT·a−1 in Alaska. The GIA low degree spherical harmonic coefficients are sensitive to rheological properties in Earth's deep interior. Our low-degree GIA estimates include geocenter motion and (Formula presented.) which provide unique constraints to understand Earth's lower mantle and ice history. Subject geodesygravityinversionmass change To reference this document use: http://resolver.tudelft.nl/uuid:95c5adb7-8046-44cb-9d8f-85f1b64a58d4 DOI https://doi.org/10.1029/2020JB020713 Embargo date 2021-10-22 ISSN 2169-9313 Source JGR Solid Earth, 126 (5), 1-19 Part of collection Institutional Repository Document type journal article Rights © 2021 Yan Jiang, Xiaoping Wu, Michiel R. van den Broeke, Peter Kuipers Munneke, Sebastian B. Simonsen, W. van der Wal, L.L.A. Vermeersen Files PDF 2020JB020713.pdf 4.42 MB Close viewer /islandora/object/uuid:95c5adb7-8046-44cb-9d8f-85f1b64a58d4/datastream/OBJ/view