| Popis: |
Due to the increased noise level of the GRACE-D accelerometer data, the measurements have to be replaced by synthetic data to ensure high quality gravity field recovery. The GRACE-FO Science Data System (SDS) provides two accelerometer transplant products: the calibrated acceleration product (ACT) and the updated hybrid accelerometer transplant (ACX). At Graz University of Technology (TUG), an alternative in-house transplant product is generated using a remove-restore technique (Behzadpur, 2021). Based on Behzadpur's work the transplant product has been further improved and its impact on monthly gravity field solutions has been analyzed. An adjusted satellite macro model and self-shadowing model have been implemented and thermal re-radiation is now considered in the processing. By determining the residual thermospheric density along the orbit and subsequently the residual drag of each satellite, the atmospheric drag model is being improved and the different orientations of the satellites are also taken into account. To further improve the accelerometer transplant, investigations were carried out to incorporate data from the GRACE-D accelerometer. |
