evidence: As a consequence of rising temperatures leading to thermal expansion of oceans, loss of ice sheets and glaciers, and variations in land water storage1, global mean sea-level (GMSL) has risen by 20 cm from 1901 to 20182. GMSL is projected to increase faster in the future3, possibly exceeding a 2 m rise in 21004. A growing body of literature indicates that sea-level rise (SLR) threatens low-lying coastal and estuarine zones worldwide5, which may have nearly 1 billion inhabitants by 20306, through a range of hazards and impacts including more frequent and/or intense coastal flooding7,8,9,10, degradation/loss of habitats/ecosystems11,12 including islands13,14 and coral reefs15, coastal erosion and shoreline changes16,17, and salinisation of surface water and groundwater18,19,20. These hazards and impacts, in turn, can damage economic assets, urban and coastal infrastructure, and coastal tourism21,22,23,24,25, influence and induce human migration26,27, impact the livelihoods and safety of vulnerable coastal populations28,29, threaten heritage sites30,31, and even jeopardise renewable energy plans32,33. [...] Gregory, J. M. et al. Concepts and Terminology for Sea Level: Mean, Variability and Change, Both Local and Global. Surveys Geophys.40, 1251–1289 (2019).