Greenland ice mass balance using GRACE gravity data

The mass balance of Greenland has been assessed with data from the Gravity Recovery and Climate Experiment (GRACE) satellite mission. Monthly data has been used through the time span of the study; January 2003 - December 2012. Level 2 data from three providers has been used. These are the Jet Propulsion Laboratory (JPL) , GeoForschungsZentrum (GFZ) and the Center for Space Research (CSR). The linear trend in this study points to -181±11 Gt/yr, -172±10 Gt/yr and -183±11 Gt/yr for the three data providers respectively. Notable corrections applied to improve the accuracy of this study are gravity leakage correction, adjustment for post-glacial rebound and non-isotropic smoothing filtering.This master thesis also gives an insight some of the mathematical background of physical geodesy and how this can be applied to use GRACE data to track changes in the gravity field. The methodology of applying this theory is explained in-depth with explanations of some natural assumptions along the way. Results are presented from correction calculations, important secular trend graphs and different time series plots of data from the three data providers. These results are compared to the works of other mentionable authors in the field of polar mass redistribution. Lastly, the thesis enlists some noteworthy strengths and weaknesses of the conducted study. To the author's knowledge, this is the first ice mass loss estimation of Greenland using GRACE level 2 Release 05 data decorrelated by non-isotropic filtering

Greenland ice mass balance using GRACE gravity data

The mass balance of Greenland has been assessed with data from the Gravity Recovery and Climate Experiment (GRACE) satellite mission. Monthly data has been used through the time span of the study; January 2003 - December 2012. Level 2 data from three providers has been used. These are the Jet Propulsion Laboratory (JPL) , GeoForschungsZentrum (GFZ) and the Center for Space Research (CSR). The linear trend in this study points to -181±11 Gt/yr, -172±10 Gt/yr and -183±11 Gt/yr for the three data providers respectively. Notable corrections applied to improve the accuracy of this study are gravity leakage correction, adjustment for post-glacial rebound and non-isotropic smoothing filtering.This master thesis also gives an insight some of the mathematical background of physical geodesy and how this can be applied to use GRACE data to track changes in the gravity field. The methodology of applying this theory is explained in-depth with explanations of some natural assumptions along the way. Results are presented from correction calculations, important secular trend graphs and different time series plots of data from the three data providers. These results are compared to the works of other mentionable authors in the field of polar mass redistribution. Lastly, the thesis enlists some noteworthy strengths and weaknesses of the conducted study. To the author's knowledge, this is the first ice mass loss estimation of Greenland using GRACE level 2 Release 05 data decorrelated by non-isotropic filtering

GRACE-derived ice-mass loss spread over Greenland

The Gravity Recovery and Climate Experiment (GRACE) monthly satellite data is used to examine the extent and magnitude of Greenland ice sheet melting for 2003-2012. We show that the well documented Greenland ice mass loss in the southern region spread to northwest Greenland in the period from2007 to 2010 and 2010 to 2012 by estimating ice mass variability over time in Greenland. The ice-mass melting is estimated to –183±11 Gt/yr. This estimation means that Greenland is still losing much more ice than gained, and continuing to contribute to global sea level rise in a warming world. Unlike other recent studies, our method employs a non-isotropic filter. A nonisotropic filter is used to decorrelate the GRACE data, since the GRACE noise structure has a non-isotropic nature