SLR is highly variable in space and time, as it results from a combination of many processes working at different temporal and spatial scales. In the 20th century, SLR was mainly caused by oceanic thermal expansion and the mass loss of mountain glaciers [Stocker et al., 2013]. In recent decades, however, the two ice sheets of Antarctica and Greenland have increasingly contributed [e.g. Bamber et al., 2018]. As highlighted in the last two Intergovernmental Panel on Climate Change (IPCC) assessment reports [Solomon et al., 2007; Stocker et al., 2013], the main uncertainty in projections of future SLR is our limited ability to model the dynamics of the Antarctic and Greenland ice sheets and robustly predict the potential emergence and rate of their collapse. Part of this uncertainty stems from the absence of atmosphere/ice-sheet/ocean feedbacks in model projections, which results in poor connections between atmospheric forcing and ice-sheet surface changes, and between ocean warming and changing ice shelf basal melt rates. Although the relative contribution of ice sheet mass loss to SLR will increase over the 21st Century, glaciers will continue to make a significant SLR contribution that must also be better quantified [Stocker et al., 2013]. Moreover, local SLR is different from the global-mean change, so it is important to better understand and quantify the regional coastal implications in order to support relevant mitigation and adaptation strategies. The project Projecting Sea-Level Rise: from Ice Sheets to Local Implications (PROTECT) aims to address all of these issues.
The overarching scientific objective of PROTECT is to assess and project changes in the land-based cryosphere with quantified uncertainties, to produce robust global, regional and local projections of SLR on a wide range of timescales (Figure 1).
The project will place particular emphasis on the low-probability, high impact scenarios of greatest interest to coastal planning stakeholders. A novelty in PROTECT is the strong interaction between these stakeholders and the sea-level scientists (ranging from glaciologists to coastal impact specialists) to identify relevant risks and opportunities from global to local scales and enhance European competitiveness in the provision of climate services.