Using GRACE Data and Geophysical Models to Analyse Earth's Dynamic Oblateness Changes

doi:10.13474/j.cnki.11-2246.2018.0119

Abstract

Abstract:

As a rotating ellipsoid,the dynamic oblateness (J₂) changes of the earth is significantly influenced by the interaction of different layers in the earth system and the redistribution of earth's fluid mass.At present,the dynamic oblateness is usually obtained from the satellite laser ranging (SLR) data.A new method is proposed to estimate changes in the earth's dynamic oblateness,which uses monthly gravity recovery and climate experiment(GRACE) gravity solutions,an ocean bottom pressure model and a glacial isostatic adjustment (GIA) model.The result shows that the time series is similar with the solution based on SLR data.The experiment shows that seasonal variations of the obtained time series are similar with different GRACE data products,which is approximate with the solution based on SLR.

Key words: earth's dynamic oblateness, SLR, GRACE, gravity field, time series variations

CLC Number:

P223

CHEN Pinxin. Using GRACE Data and Geophysical Models to Analyse Earth's Dynamic Oblateness Changes[J]. 测绘通报, 2018, 0(4): 100-103.

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