The multidisciplinary MUST2SEA project aims at a better understanding of the current tectonic evolution of Sulawesi (Indonesia) with more emphasis on both inter- and post-seismic plate deformations. It will combine up to two decades of space geodetic data (global navigation systems, synthetic aperture radar and radar altimetry missions) with scientific findings obtained during previous successful NWO/GO and EU-ASEAN projects (GEODYSSEA, SEAMERGES, GEO2TECDI-1/2). The final goal is to provide a better assessment of seismic risk, in particular for the area of Palu, the second largest city on the island. Our exclusive GPS database (1992-present) remains key input to this study as it provides a high spatial coverage in SE Asia. Our project includes making data and processing products readily accessible (online) to the global scientific community and disseminating the final results to the (local) authorities and the general public in Palu. The GPS time series (displacement rates) exhibit numerous co- and post-seismic 3D deformation patterns, as well as measurements of vertical motions that provide valuable input to absolute land-subsidence and relative sea-level change studies. We will exploit the latest state-of-the-art geodetic techniques to re-analyze the entire geodetic database and also try detect any additional land surface (vertical) deformation signals that might have been overlooked in previous analyses (e.g. earthquake pre-cursor events) and evaluate their significance using state of the art geophysical models. This requires a multi-disciplinary approach combining different expertise, methods and data, both in situ and by satellites.

The RISC2IDNSI project employs space‐geodetic techniques and advanced geophysical models to investigate the long‐term (1992‐2022) seismic behaviour of the Palu‐Koro fault in Sulawesi, Eastern Indonesia. This active fault generated a large (Mw 7.5) earthquake in 2018 through Palu city, followed by an unexpected and devastating tsunami in the Palu Bay.

An estimated 60% of the presently observed sea level rise is attributed to melting glaciers, ice caps and ice sheets. The contribution of Arctic glaciers and especially the Greenland ice sheet (GrIS) has more than doubled over the period 1961-2008, and is likely to increase further when global temperature increases over the coming century. A first order effect of increasing temperatures on the glacier mass budget is an increase in surface melt. However, not all melt contributes to mass loss via runoff, because part of the meltwater refreezes in the cold snow. For the GrIS, an estimated 30-50% of all meltwater refreezes. Infiltration of water and subsequent refreezing is not well included in existing mass balance models, and estimates of refreezing are not well validated due to a lack of observations. Given the importance of refreezing for the mass budget of Arctic glaciers, in this proposal we focus on improving refreezing estimates for the GrIS and therewith other Arctic ice masses, by using a combined observational and modelling approach. Existing satellite and in-situ observations, complemented with detailed snow temperature observations to be carried out in western Greenland (K-transect), will be used to evaluate the mass balance terms and refreezing modelled with the regional climate model RACMO2, which includes a multi-layer snow model. After improvements to the snow model have been implemented and evaluated, RACMO2 will be run for the period 1958-present-2100 in order to study the role of refreezing in the mass balance of the GrIS in a changing climate.