Improved modelling of non-tidal mass variations for optimized gravity fields analysis
High-frequency mass variations cannot be measured adequately from space due to undersampling. They are removed from the measurements beforehand using geophysical models (de-aliasing). Any model error fully propagates into the final gravity field results. IMPLY aims in the improved modelling of non-tidal short-term mass variations (ocean, atmosphere and hydrology) and their uncertainties in order to optimize GRACE, GOCE and next generation gravity field data analysis. In particular the expected results are:
- Improved geophysical models of global mass variations specifically related to long-term stability and standards applied in these models.
- Studies on the significance of the use of hydrology models and/or GRACE daily solutions for de-aliasing.
- Generating a time series of refined de-aliasing coefficients. This includes global solutions to be applied for standard gravity field analysis as well as regional refinements needed by other projects of SPP1257.
- Review, extension, speed up of de-aliasing and error-propagation software developed before within the SPP 1257.
Results of IMPLY will lead to improved modelling of high frequency time-variable mass variations and their uncertainties. This not only drives the performance of current gravity field missions, but also is one of the main issues to be solved for next-generation gravity field missions with significantly improved observation accuracy.
Contact: Dr. Henryk Dobslaw, Inga Bergmann-Wolf