Print Email Facebook Twitter Observed changes in the Earth’s dynamic oblateness from GRACE data and geophysical models Title Observed changes in the Earth’s dynamic oblateness from GRACE data and geophysical models Author Sun, Y. Ditmar, P. Riva, R. Faculty Civil Engineering and Geosciences Department Geoscience & Remote Sensing Date 2015-09-18 Abstract A new methodology is proposed to estimate changes in the Earth’s dynamic oblateness (?J2 or equivalently, ?5??C20) on a monthly basis. The algorithm uses monthly Gravity Recovery and Climate Experiment (GRACE) gravity solutions, an ocean bottom pressure model and a glacial isostatic adjustment (GIA) model. The resulting time series agree remarkably well with a solution based on satellite laser ranging (SLR) data. Seasonal variations of the obtained time series show little sensitivity to the choice of GRACE solutions. Reducing signal leakage in coastal areas when dealing with GRACE data and accounting for self-attraction and loading effects when dealing with water redistribution in the ocean is crucial in achieving close agreement with the SLR-based solution in terms of de-trended solutions. The obtained trend estimates, on the other hand, may be less accurate due to their dependence on the GIA models, which still carry large uncertainties. Subject J2C20satellite laser rangingglacial isostatic adjustmenttemporal gravity field variationsmass transport To reference this document use: http://resolver.tudelft.nl/uuid:65ba77b0-f060-4d58-a4e1-25366e90c99a Publisher Springer ISSN 0949-7714 Source https://doi.org/10.1007/s00190-015-0852-y Source Journal of Geodesy, 2015 Part of collection Institutional Repository Document type journal article Rights © 2015 The Author(s)This article is published with open access at Springerlink.com Files PDF Sun_2015.pdf 378.15 KB Close viewer /islandora/object/uuid:65ba77b0-f060-4d58-a4e1-25366e90c99a/datastream/OBJ/view