Different from calibrations previously conducted using the dynamic method, the GRACE-Level-1B non-conservative force data from the space-borne accelerometers between 1 January to 31 December, 2009, released by the Jet Propulsion Laboratory in the United States of America, is for the first time ever effectively calibrated using the priori Earth gravitational field model based on an improved energy conservation principle. The results are shown as follows: 1) The non-conservative force data from the space-borne accelerometers and attitude data from the star camera assembly are basically the same as the anticipated accuracies; 2) the systematic error of the raw non-conservative force data leads to a disturbed geopotential error linear drift of about 0.4 m2
per day, however, the error is only 0.01 m2
using the calibrated non-conservative force data, and a reasonable physical explanation is provided; 3) the advantages and disadvantages of calibrating non-conservative force data using the energy conservation principle and dynamic method are compared in detail; and 4) because the signal of the Earth’s gravitational field is sensitive to the systematic error of non-conservative force data from the space-borne accelerometers, the precise calibration of non-conservative force data is a key factor for the highly accurate recovery of the Earth gravitational field with high spatial resolution.
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