On the capability of non-dedicated GPS-tracked satellite constellations for estimating mass variations: case study SWARM

Scientific Conference (2013, September)

GOCE long-wavelength gravity field recovery from 1s-sampled kinematic orbits using the acceleration approach

in GGHS2012 - Gravity, Geoid and Height Systems 2012 (2013)

GOCE long-wavelength gravity field recovery from high-low satellite-to-satellite-tracking using the acceleration approach

Poster (2012, April)

Assessment of aliasing effect of white noise on different solutions in gravity recovery simulations of a GRACE-like mission

Scientific Conference (2011, July)

Long wavelength gravity field determination from GOCE using the acceleration approach

in Proceedings of the 4th GOCE User Workshop, ESA SP-696 (2011, April)

Spaceborne Gravimetric Satellite Constellations and Ocean Tides: aliasing effects

in Geophysical Journal International (2010), (181), 789-805

Ocean tides redistribute mass at high temporal frequencies. Satellite missions that aim to observe medium to low frequency mass variations need to take into account this rapidly varying mass signal ... [more ▼]

Ocean tides redistribute mass at high temporal frequencies. Satellite missions that aim to observe medium to low frequency mass variations need to take into account this rapidly varying mass signal. Correcting for the effects of ocean tides by means of imperfect models might hamper the observation of other temporal gravity field signals of interest. This paper explores different methods for mitigating aliasing errors for the specific example of observing mass variations due to land hydrology, including temporal filtering of time-series of gravity solutions, spatial smoothing and the use of satellite constellations. For this purpose, an Earth System Model (ESM) was constructed, which included state-of-the-art time varying components for ocean, atmosphere, solid Earth, hydrology, ice-sheets and ocean tides. Using the ESM, we simulated the retrieval of the hydrologically driven gravity field changes using a number of different satellite constellations. We find that (1) the ocean tide aliasing strongly depends on the satellite constellation, the choice of orbital parameters and the length of the data span; (2) the aliasing effect manifests itself differently for different geographical regions; (3) the aliasing causes a peculiar striping pattern along the ground track of the satellite orbits; (4) optimizing the choice of orbital parameters of a single GRACE-type tandem can be more effective at reducing the aliasing of ocean tide model errors than flying more tandems. Finally, we corroborate the experiences with GRACE data analysis that appropriate post-processing techniques can significantly improve the quality of the retrieved gravity changes. [less ▲]