The significance of interseismic vertical land movement at convergent plate boundaries in probabilistic sea-level projections for AR6 scenarios: The New Zealand case.
- Author
- T. Naish, R. Levy, I. Hamling, S. Hreinsdóttir, P. Kumar, G. G. Garner, R. E. Kopp, N. Golledge, R. Bell, R. Paulik, J. Lawrence, P. Denys, T. Gillies, S. Bengtson, A. Howell, K. Clark, D. King, N. Litchfield, R. Newnham
- Year
- 2024
- Journal / Source
- Earth's Future
- Volume
- 12
- Number
- e2023EF004165.
- Pages
- 27 pp.
- Summary
- This study outlines an approach for deriving probabilistic projections of relative sea‐level change that account for changes in land surface elevation continuously along a coastline. Previous sea‐level projections that included vertical land movements (VLMs) were restricted to tide gauge locations. To provide spatial‐resolution required by practitioners for effective adaptation planning, we have combined elevations measured using satellite radar data with measurements from land‐based Global Navigation Satellite System (GNSS) receivers to build a continuous VLM database showing land uplift and subsidence(sinking) for the entire coastline of New Zealand. We integrate these data into probabilistic sea‐level projection methodology used in Intergovernmental Panel on Climate Change (IPCC) Assessment Report 6 (AR6) for the range of future climate scenarios. Our approach could be applied to any region of the world where the coastline is affected by VLM due to secular tectonic deformation. Downward land movement >2 mm/y makes a significant contribution in sea‐level projections for all climate scenarios out to the end of this century. This means that adaptation planning decision thresholds, such as those linked to the impacts of coastal flooding and inundation, may be brought forward by decades.