High‐resolution CSR GRACE RL05 mascons

The determination of the gravity model for the Gravity Recovery and Climate Experiment (GRACE) is susceptible to modeling errors, measurement noise, and observability issues. The ill-posed GRACE estimation problem causes the unconstrained GRACE RL05 solutions to have north-south stripes. We discuss the development of global equal area mascon solutions to improve the GRACE gravity information for the study of Earth surface processes. These regularized mascon solutions are developed with a 1° resolution using Tikhonov regularization in a geodesic grid domain. These solutions are derived from GRACE information only, and no external model or data is used to inform the constraints. The regularization matrix is time variable and will not bias or attenuate future regional signals to some past statistics from GRACE or other models. The resulting Center for Space Research (CSR) mascon solutions have no stripe errors and capture all the signals observed by GRACE within the measurement noise level. The solutions are not tailored for specific applications and are global in nature. This study discusses the solution approach and compares the resulting solutions with postprocessed results from the RL05 spherical harmonic solutions and other global mascon solutions for studies of Arctic ice sheet processes, ocean bottom pressure variation, and land surface total water storage change. This suite of comparisons leads to the conclusion that the mascon solutions presented here are an enhanced representation of the RL05 GRACE solutions and provide accurate surface-based gridded information that can be used without further processing.

[1]  R. Nerem,et al.  Recent Greenland Ice Mass Loss by Drainage System from Satellite Gravity Observations , 2006, Science.

[2]  F. Landerer,et al.  Accuracy of scaled GRACE terrestrial water storage estimates , 2012 .

[3]  M. Watkins,et al.  The gravity recovery and climate experiment: Mission overview and early results , 2004 .

[4]  W. Tad Pfeffer,et al.  Recent contributions of glaciers and ice caps to sea level rise , 2012, Nature.

[5]  E. Schrama,et al.  Revisiting Greenland ice sheet mass loss observed by GRACE , 2011 .

[6]  Don P. Chambers,et al.  Observing seasonal steric sea level variations with GRACE and satellite altimetry , 2006 .

[7]  Jens Schröter,et al.  A pattern‐filtering method for the determination of ocean bottom pressure anomalies from GRACE solutions , 2008 .

[8]  Olaf Boebel,et al.  Validation of GRACE Gravity Fields by In-Situ Data of Ocean Bottom Pressure , 2010 .

[9]  Di Long,et al.  Hydrologic implications of GRACE satellite data in the Colorado River Basin , 2015 .

[10]  R. Rietbroek,et al.  Key Points: @bullet Consistent Method for Estimating Mass Balances from Grace @bullet Mascon Technique @bullet Evaluate Systematic Errors Gia Correction a Mascon Approach to Assess Ice Sheet and Glacier Mass Balances and Their Uncertainties from Grace Data , 2022 .

[11]  D. Chambers,et al.  Estimating Geocenter Variations from a Combination of GRACE and Ocean Model Output , 2008 .

[12]  Isabella Velicogna,et al.  Regional acceleration in ice mass loss from Greenland and Antarctica using GRACE time‐variable gravity data , 2014 .

[13]  Don P. Chambers,et al.  Evaluation of Release-05 GRACE time-variable gravity coefficients over the ocean , 2012 .

[14]  V. M. Tiwari,et al.  Dwindling groundwater resources in northern India, from satellite gravity observations , 2009 .

[15]  Eric Rignot,et al.  Timing and origin of recent regional ice-mass loss in Greenland , 2012 .

[16]  S. Swenson,et al.  Satellites measure recent rates of groundwater depletion in California's Central Valley , 2011 .

[17]  F. Bryan,et al.  Time variability of the Earth's gravity field: Hydrological and oceanic effects and their possible detection using GRACE , 1998 .

[18]  M. Watkins,et al.  Improved methods for observing Earth's time variable mass distribution with GRACE using spherical cap mascons , 2015 .

[19]  Don P. Chambers,et al.  A Global Evaluation of Ocean Bottom Pressure from GRACE, OMCT, and Steric-Corrected Altimetry , 2010 .

[20]  N. G. Val’es,et al.  CNES/GRGS 10-day gravity field models (release 2) and their evaluation , 2010 .

[21]  Eric Rignot,et al.  A Reconciled Estimate of Ice-Sheet Mass Balance , 2012, Science.

[22]  Jeffrey P. Walker,et al.  THE GLOBAL LAND DATA ASSIMILATION SYSTEM , 2004 .

[23]  Peter Schwintzer,et al.  Seasonal variation of ocean bottom pressure derived from Gravity Recovery and Climate Experiment (GRACE): Local validation and global patterns , 2005 .

[24]  B. Scanlon,et al.  GRACE satellite monitoring of large depletion in water storage in response to the 2011 drought in Texas , 2013 .

[25]  Ichiro Fukumori,et al.  Mechanisms Controlling the Interannual Variation of Mixed Layer Temperature Averaged over the Niño-3 Region , 2007 .

[26]  Oliver Baur,et al.  GRACE‐derived ice‐mass variations over Greenland by accounting for leakage effects , 2009 .

[27]  John M. Wallace,et al.  Arctic Ocean Circulation Patterns Revealed by GRACE , 2014 .

[28]  Byron D. Tapley,et al.  Interannual variability of Greenland ice losses from satellite gravimetry , 2011 .

[29]  Jean-Charles Marty,et al.  Temporal gravity field models inferred from GRACE data , 2007 .

[30]  Ichiro Fukumori,et al.  A Partitioned Kalman Filter and Smoother , 2002 .

[31]  J. Famiglietti,et al.  Satellite-based estimates of groundwater depletion in India , 2009, Nature.

[32]  I. Velicogna.  Increasing rates of ice mass loss from the Greenland and Antarctic ice sheets revealed by GRACE , 2009 .

[33]  J. B. Thomas.  An Analysis of Gravity-Field Estimation Based on Intersatellite Dual-1-Way Biased Ranging , 1999 .

[34]  M. Cheng,et al.  Variations in the Earth's oblateness during the past 28 years , 2004 .

[35]  S. Swenson,et al.  Post‐processing removal of correlated errors in GRACE data , 2006 .

[36]  Isabella Velicogna,et al.  Time‐variable gravity observations of ice sheet mass balance: Precision and limitations of the GRACE satellite data , 2013 .

[37]  Louise Sandberg Sørensen,et al.  Scatter of mass changes estimates at basin scale for Greenland and Antarctica , 2013 .

[38]  Srinivas Bettadpur,et al.  Reducing errors in the GRACE gravity solutions using regularization , 2012, Journal of Geodesy.

[39]  Steven M. Klosko,et al.  Global Mass Flux Solutions from GRACE: A Comparison of Parameter Estimation Strategies - Mass Concentrations Versus Stokes Coefficients , 2010 .

[40]  I. Sasgen,et al.  Antarctic ice-mass balance 2003 to 2012: regional reanalysis of GRACE satellite gravimetry measurements with improved estimate of glacial-isostatic adjustment based on GPS uplift rates , 2013 .

[41]  D. Rowlands,et al.  Recent glacier mass changes in the Gulf of Alaska region from GRACE mascon solutions , 2008, Journal of Glaciology.

[42]  Scott B. Luthcke,et al.  Improving global mass flux solutions from Gravity Recovery and Climate Experiment (GRACE) through forward modeling and continuous time correlation , 2010 .

[43]  D. Randall,et al.  A Potential Enstrophy and Energy Conserving Numerical Scheme for Solution of the Shallow-Water Equations on a Geodesic Grid , 2002 .

[44]  M. Watkins,et al.  GRACE Measurements of Mass Variability in the Earth System , 2004, Science.

[45]  J. Camp,et al.  Antarctica, Greenland and Gulf of Alaska land-ice evolution from an iterated GRACE global mascon solution , 2013, Journal of Glaciology.

[46]  J. Wahr,et al.  Computations of the viscoelastic response of a 3-D compressible Earth to surface loading: an application to Glacial Isostatic Adjustment in Antarctica and Canada , 2012 .