Comparisons of atmospheric data and reduction methods for the analysis of satellite gravimetry observations

Forootan, Ehsan ORCID: https://orcid.org/0000-0003-3055-041X, Didova, O., Kusche, J. and Locher, A. 2013. Comparisons of atmospheric data and reduction methods for the analysis of satellite gravimetry observations. Journal of Geophysical Research: Solid Earth 118 (5) , pp. 2382-2396. 10.1002/jgrb.50160

Preview

PDF - Presentation Download (4MB) | Preview

Abstract

[1] The Gravity Recovery and Climate Experiment (GRACE) derived gravity solutions contain errors mostly due to instrument noise, anisotropic spatial sampling, and temporal aliasing. Improving the quality of satellite gravimetry observations, in terms of using more sensitive sensors and/or increasing the spatial isotropy, has been discussed in the context of the designed scenarios of future satellite gravimetry missions. Temporal aliasing caused by incomplete reducing of background models, however, is still a factor that affects the quality of the gravity field solutions. This paper specifically explores the possible physical, geometrical, and numerical modifications of the three‒dimensional (3‒D) integration approach to eliminate the high‒frequency atmospheric effects from satellite gravimetry observations. The new modified 3‒D approach is then applied to compute new sets of atmospheric dealiasing products, using atmospheric fields from the European Centre for Medium‒Range Weather Forecasts (ECMWF) operational analysis model and ERA‒Interim reanalysis. Impacts of modifications are compared to the prelaunch baseline and the current error‒curve of GRACE as well as an error‒curve of a Bender‒type multiorbit satellite configuration. Specifically, we found that using latitude‒dependent radius, latitude‒ and altitude‒dependent gravity accelerations along with numerical modifications have a considerable impact on the 3‒D integral. Comparing the new products to those of GRACE Atmosphere and Ocean Dealiasing level‒1B shows a nonnegligible difference with respect to the prelaunch baseline of GRACE and a possible Bender‒type mission up to harmonic degrees 13 and 50, respectively. A big difference is also found between the derived dealiasing products from ECMWF operational analysis and ERA‒Interim indicating the importance of input parameters on the final atmospheric dealiasing products.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Earth and Environmental Sciences
Subjects:	G Geography. Anthropology. Recreation > GE Environmental Sciences
Publisher:	American Geophysical Union
ISSN:	2169-9356
Date of Acceptance:	12 March 2013
Last Modified:	05 May 2023 10:43
URI:	https://orca.cardiff.ac.uk/id/eprint/94856

Citation Data

Cited 28 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item