A global analysis of subsidence, relative sea-level change and coastal flood exposure
- 1Global Climate Forum, Adaptation and social learning, Berlin, Germany (daniel.lincke@globalclimateforum.org)
- 2Tyndall Centre for Climate Change Research, University of East Anglia, Norwich, UK
- 3Division of Resource Economics, Albrecht Daniel Thaer-Institute and Berlin Workshop in Institutional Analysis of Social-Ecological Systems (WINS), Humboldt-University, Berlin, Germany
- 4Department of Life and Environmental Sciences, Faculty of Science and Technology, Bournemouth University, UK
- 5Kiel University, Department of Geography, Kiel, Germany
- 6LEGOS, Université de Toulouse, CNES, CNRS, UPS, IRD, 31400 Toulouse, France.
- 7School of Engineering, University of Southampton, Southampton, UK
- 8School of Geographic Sciences, East China Normal University, Shanghai, 200241, China
Climate-induced sea-level rise and vertical land movements, including natural and human-induced subsidence in sedimentary coastal lowlands, combine to change relative sea levels around the world's coast. Global-average coastal relative sea-level rise was 2.5 mm/yr over the last two decades. However, as coastal inhabitants are preferentially located in subsiding locations, they experience an average relative sea-level rise up to four times faster at 7.8 to 9.9 mm/yr. This first global quantification of relative sea-level rise shows that the resulting impacts, and adaptation needs are much higher than reported global sea-level rise measurements would suggest. Hence, coastal subsidence is an important global issue that needs more assessment and action. In particular, human-induced subsidence in and surrounding coastal cities can be rapidly reduced with appropriate policy measures for groundwater utilization and drainage. This offers substantial and rapid benefits in terms of reducing growth of coastal flood exposure due to relative sea-level rise.
How to cite: Lincke, D., Nicholls, R. J., Hinkel, J., Brown, S., Vafeidis, A. T., Meyssignac, B., Hanson, S. E., Merkens, J., and Fang, J.: A global analysis of subsidence, relative sea-level change and coastal flood exposure, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-14985, https://doi.org/10.5194/egusphere-egu21-14985, 2021.
