Hao Zhou^a,b, Zhicai Luo^a,c,Zebing Zhou^a, Bo Zhong^d, Houze Hsu^a,b
a MOE Key Laboratory of Fundamental Physical Quantities Measurement, School of Physics, Huazhong University of Science and Technology, Wuhan, PR China
b State Key Laboratory of Geodesy and Earth’s Dynamics, Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan, PR China
c State Key Laboratory of Information Engineering in Surveying, Mapping, and Remote Sensing, Wuhan University, Wuhan, PR China
d School of Geodesy and Geomatics, Wuhan University, Wuhan, PR China
Received 7 November 2016; received in revised form 26 April 2017; accepted 28 April 2017
Available online 8 May 2017

Abstract
The modified dynamic approach, where the observation vector and design matrix of observation equation are simultaneously filtered by empirical parameters, is implemented in this study. Using approximately 13 years (spanning from January 2003 to April 2015) of Gravity Recovery and Climate Experiment (GRACE) Level 1B data published by JPL and kinematic orbits published by ITSG, we developed a new GRACE static gravity field model called HUST-Grace2016s complete to degree and order 160. To evaluate the quality of our model, other GRACE-only gravity field models including AIUB-GRACE03S, GGM05S, ITG-Grace2010s, ITSG-Grace2014s and Tongji-GRACE01, are introduced for comparison. The difference degree amplitudes in terms of geoid height of our HUSTGrace2016s relative to GOCO05c are smaller than 1 mm and 1 cm before degree 100 and degree 138, respectively. In terms of global gravity anomalies and geoid heights relative to GOCO05c, the RMS values of our model up to degree 140 are 4.31 cm and 0.87 mGal respectively, which are smaller compared to AIUB-GRACE03S, GGM05S and Tongji-GRACE01. In addition, validated with GPSleveling data in North America and the Netherlands, the standard deviation values of our HUST-Grace2016s model are 46.56 cm and 24.80 cm respectively, which also performs better than AIUB-GRACE03S, GGM05S and Tongji-GRACE01. 2017 COSPAR. Published by Elsevier Ltd. All rights reserved.

http://dx.doi.org/10.1016/j.asr.2017.04.026