Storm clustering and its influence on coastal morphology and defence

The coastal zone is widely recognised as important at national, European and global levels, but is facing increasing pressures from climate change. The recent Government's Committee on Climate Change 2018 report highlights the urgency of increasing threats from flooding and coastal erosion in the UK. It calls for improvements in calculation of failure probabilities of coastal structures, reductions in uncertainty about coastal erosion and better understanding of coastal geomorphology, and its response to climate change. Improved understanding of the characteristics of extreme events, and the dynamic response of the coast, is essential to deliver on these aims.

Storms strongly influence coastal flooding and erosion in the UK, via extreme sea levels and waves. Most previous studies and risk assessments have tended to only assess the impacts of individual storms and have rarely considered sequences of storm events on different time-scales. Temporal clustering of extreme sea levels could lead to amplified flood or erosion damages due to attritional effects on defences and inadequate recovery/repair time of natural (e.g., beaches) and man-made (e.g. revetments) elements within the coastal protection system. Conditions of these are almost always considered static in coastal modelling studies and this potentially leads to underestimation of flood and erosion risk when several events occur in rapid succession. Building on a large previous EPSRC-funded project called Flood MEMORY, this PhD aims to improve understanding of the impact that sequences of storm events have on the dynamic response of hard and soft coasts.