A new global time-variable gravity mascon solution: Signal and error analysis

Tuesday, 16 December 2014
Bryant Loomis, NASA Goddard Space Flight Center, Greenbelt, MD, United States, Scott B Luthcke, Goddard Space Flight Center, Severna Park, MD, United States and Terence J Sabaka, NASA Goddard Space Flight Center, Planetary Geodynamics Laboratory, Greenbelt, MD, United States
The latest time-variable global gravity mascon solution product from the NASA Goddard Space Flight Center is described and analyzed. This most recent solution is estimated directly from the reduction of the GRACE L1B RL2 data with an optimized set of arc parameters and the full noise covariance. The mascons are estimated monthly with 1-arc-degree equal-area sampling where anisotropic spatial constraints are applied to maximize the recovery of signal while minimizing noise and signal leakage across the geographic constraint region boundaries. Analysis of the solution signals and errors is presented at global and regional scales and comparisons to the GRACE project solutions and independent models are presented. Time series of cryospheric and hydrologic regions are analyzed with the complete Ensemble Empirical Mode Decomposition (EEMD) with adaptive noise algorithm, which adaptively sifts the signal into intrinsic frequency-ordered modes. Lastly, the impact of different solution components is discussed.