The overall aim of the project is to produce global, consistent and statistically-rigorous estimates of (i) glacial isostatic adjustment (GIA), (ii) land ice mass trends, (iii) land hydrology trends and (iv) sea level budget for a common epoch.

These estimates will be data-driven (as opposed to deterministically modelled) and will combine a suite of satellite, model and in-situ data  They will, for the first time, be consistent with each other and with physical constraints on the coupled system (e.g. conservation of mass and salt).

To this end, the key research aims are to:
(1) Solve for GIA without the use of forward models that rely on assumptions about ice history;
(2) Solve for the mass trends of land ice;
(3) Solve for the global exchange of mass (of water) between land and ocean;
(4) Solve for the different components that contribute to changes in ocean density; and
(5) Develop and showcase a new approach to tackling signal processing in geostatistics.

Six main objectives have been identified as important steps in addressing these aims, but each objective represents a major scientific achievement and advance in its own right:
Objective 1: Development of the methodology and software to undertake multivariate spatio-temporal modelling at a global scale.
Objective 2: Obtain a data-driven solution for global GIA, consistent with global mean sea level, gravity data, sea level budget and GPS observations.
Objective 3: Reconciled sea level budget assessment for 1981-2020.
Objective 4: Spatially distributed land ice mass balance 1992-2020 consistent with in-situ and satellite-based observations and the barystatic contribution to global mean sea level.
Objective 5: Re-evaluation of the twentieth century sea level rate from the tide gauge record.
Objective 6: Catchment-scale land hydrology trends for 2003-2020; spatially-integrated signal for pre-GRACE period.