Using satellite laser ranging to measure ice mass change in Greenland and Antarctica

Abstract. A least squares inversion of satellite laser ranging (SLR) data over Greenland and Antarctica could extend gravimetry-based estimates of mass loss back to the early 1990s and fill any future gap between the current Gravity Recovery and Climate Experiment (GRACE) and the future GRACE Follow-On mission. The results of a simulation suggest that, while separating the mass change between Greenland and Antarctica is not possible at the limited spatial resolution of the SLR data, estimating the total combined mass change of the two areas is feasible. When the method is applied to real SLR and GRACE gravity series, we find significantly different estimates of inverted mass loss. There are large, unpredictable, interannual differences between the two inverted data types, making us conclude that the current 5×5 spherical harmonic SLR series cannot be used to stand in for GRACE. However, a comparison with the longer IMBIE time series suggests that on a 20-year time frame, the inverted SLR series' interannual excursions may average out, and the long-term mass loss estimate may be reasonable.

[1]  Quantifying the resolution level where the GRACE satellites can separate Greenland's glacial mass balance from surface mass balance , 2015 .

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

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

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

[5]  Matt A. King,et al.  A new glacial isostatic adjustment model for Antarctica: calibrated and tested using observations of relative sea‐level change and present‐day uplift rates , 2012 .

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

[7]  R. Nerem,et al.  Ice mass change in Greenland and Antarctica between 1993 and 2013 from satellite gravity measurements , 2017, Journal of Geodesy.

[8]  Eric Rignot,et al.  Acceleration of the contribution of the Greenland and Antarctic ice sheets to sea level rise , 2011 .

[9]  Minkang Cheng,et al.  Variations of the Earth's figure axis from satellite laser ranging and GRACE , 2011 .

[10]  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 .

[11]  John C. Ries,et al.  The unexpected signal in GRACE estimates of $$C_{20}$$C20 , 2017 .

[12]  Koji Matsuo,et al.  Accelerated ice mass depletion revealed by low‐degree gravity field from satellite laser ranging: Greenland, 1991–2011 , 2013 .

[13]  D. Chambers,et al.  Uncertainty estimates of a GRACE inversion modelling technique over Greenland using a simulation , 2013 .

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

[15]  J. Ray,et al.  Effect of the satellite laser ranging network distribution on geocenter motion estimation , 2009 .

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

[17]  Kirill Khvorostovsky,et al.  Recent Ice-Sheet Growth in the Interior of Greenland , 2005, Science.

[18]  J. Ray,et al.  Geocenter motion and its geodetic and geophysical implications , 2012 .

[19]  R. Nerem,et al.  Observations of annual variations of the Earth's gravitational field using satellite laser ranging and geophysical models , 2000 .

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

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

[22]  Graeme L. Stephens,et al.  Snowfall‐driven mass change on the East Antarctic ice sheet , 2012 .

[23]  R. Nerem,et al.  Recent changes in the Earth's oblateness driven by Greenland and Antarctic ice mass loss , 2011 .

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

[25]  B. Smith,et al.  Rates of southeast Greenland ice volume loss from combined ICESat and ASTER observations , 2008 .

[26]  T. Lee,et al.  ECCO2: High Resolution Global Ocean and Sea Ice Data Synthesis , 2008 .

[27]  M. Cheng,et al.  Geocenter Variations from Analysis of SLR Data , 2013 .

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

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

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

[31]  Srinivas Bettadpur,et al.  The pole tide and its effect on GRACE time‐variable gravity measurements: Implications for estimates of surface mass variations , 2015 .

[32]  E. van Meijgaard,et al.  The KNMI regional atmospheric climate model RACMO version 2.1 , 2008 .

[33]  R. Dach,et al.  Time variable Earth’s gravity field from SLR satellites , 2015, Journal of Geodesy.

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