EGU22-10759
https://doi.org/10.5194/egusphere-egu22-10759
EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Insidious Retreat of the Holderness Coastline: Capturing Spatial and Temporal Patterns of Failure using Terrestrial Laser Scanning (TLS) 

Serena L Teasdale1, Christopher R Hackney2, David J Milan3, Georgina L Bennett4, and Daniel R Parsons1
Serena L Teasdale et al.
  • 1Energy and Environment Institute, University of Hull, Hull, HU6 7RX, UK (s.l.teasdale-2017@hull.ac.uk)
  • 2School of Geography, Politics and Sociology, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK
  • 3Department of Geography, Geology and Environment, University of Hull, Hull HU6 7RX, UK
  • 4Department of Geography, University of Exeter, EX4 4RJ, UK

The Holderness coastline of Eastern England is the fastest eroding coastline in Europe. The coast is characterised by ‘soft sediment’ tills, which make it distinctly susceptible to cliff retreat, in turn, these pose a socio-economic threat to local communities. The controls and future projections of the rates and patterns of retreat rely upon robust monitoring and process-based understanding of the geomorphological processes. Herein, we report on a 12-month monitoring study (June 2019 to May 2020) along a 220 m stretch of the Holderness coastline (Withernsea), whereby the spatial and temporal patterns of failure were captured using terrestrial LiDAR. Failure footprint, volumetric change and total eroded volume of the cliffs were estimated and compared against local hydrodynamic and meteorological records. The results reveal that >36% of individual failure events occurred solely in the upper portions (upper 75% vertical height) of the cliff, with a further >38% over the central section of the cliff face, with <26% occurring solely at the cliff toe (lower 25% cliff height). These findings disprove the widely accepted assumption that failure is primarily driven by wave attack, and we instead propose that instability in soft cliffs occurs as a result of moisture-driven ‘structural weakening’ with the influence of wave action primarily acting to remove failed material.

How to cite: Teasdale, S. L., Hackney, C. R., Milan, D. J., Bennett, G. L., and Parsons, D. R.: Insidious Retreat of the Holderness Coastline: Capturing Spatial and Temporal Patterns of Failure using Terrestrial Laser Scanning (TLS) , EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-10759, https://doi.org/10.5194/egusphere-egu22-10759, 2022.