News release

Removing sea defences may reduce impact of coastal flooding

Ref: 12/208

03 December 2012

Professor Robert Nicholls

A study involving a scientist from the University of Southampton, which shows that ensuring continued flood protection for low lying coastal areas may mean sacrificing cliff top communities to the sea, has won the 2012 Lloyds Science of Risk prize for Climate Change research.

Robert Nicholls, Professor of Coastal Engineering at the University of Southampton and co-author of this study, says the research – which will be further developed in a new book he is leading, to be launched in Spring 2013 – says that the benefits of protecting our coastline from erosion must be balanced against the impacts of coastal flooding.

“The trade-off between protecting cliffs and their role in naturally nourishing our protective beaches will lead to difficult decisions, especially as sea levels are rising and finance is in short supply. This requires strategic planning for the future.”

Professor Nicholls was part of a research team from the Tyndall Centre for Climate Change Research which, by focussing on a 72km stretch of shoreline along the East Anglian coast, detailed the interconnection between the two risks of erosion and flooding and show that in some cases, allowing natural erosion could reduce the impact of flooding associated with rising sea levels.

Coastal defences put in place over the last century or so have re-shaped the UK coastline, artificially protecting some areas, but at the expense of beaches in adjacent areas.

This man-made situation increases the risk of flooding in low lying coastal settlements where beaches act as a natural flood defence. Beach levels can be artificially recharged, but maintaining this indefinitely along large stretches of coastline is costly and likely to be unsustainable.

Richard Dawson, Professor of Earth Systems Engineering at Newcastle University and lead author of this study, adds: “Coastal areas typify the environmental challenge our society faces - their beauty and economic opportunities attracts settlement and they include some of our most important ecosystems and most productive farmland. Yet this exposes us to hazards such as erosion and flooding which will be exacerbated by sea-level rise.

“Clearly we can’t, and wouldn’t want to, remove all our sea defences, but there are difficult trade-offs to be made in prioritising coastal management measures.

“Our research provides a common platform to get all parties round the table – local residents, policy-makers, insurers, scientists and farmers to name but a few – to understand each other’s perspectives, discuss potential compensatory arrangements, and collectively decide the best way forward.”

Notes for editors

  1. 1. ‘Integrated analysis of risks of coastal flooding and cliff erosion under scenarios of long term change’ by Richard Dawson, Mark Dickson, Robert Nicholls, Jim Hall, Mike Walkden, Peter Stansby, Mustafa Mokrech, Julie Richards, Jian Zhou, Jessica Milligan, Andrew Jordan, Stephen Pearson, Jon Rees, Paul Bates, Sotiris Koukoulas, Andrew Watkinson. Climatic Change, Vol 95 pp249–288 (2009).

    2. The paper won the 2012 Lloyds Science of Risk prize in the Climate Change category:

    3. This research was part of the Tyndall Centre coastal programme and was funded by the Natural Environment Research Council, the Engineering & Physical Sciences Research Council and the Economic and Social Research Council.

    4. “Broad Scale Coastal Simulation: New techniques to understand and manage shorelines in the third millennium”, published by Springer and edited by Professor Robert Nicholls (University of Southampton), Professor Richard Dawson (Newcastle University) and Dr Sophie Day (University of Southampton), will update this research and provide further insights into the Tyndall Centre’s coastal research. The book is due for publication in Spring 2013.

    5. The Tyndall Centre for Climate Change Research is an active and expanding partnership between the Universities of East Anglia (headquarters), Cambridge, Cardiff, Manchester, Newcastle, Oxford, Southampton, Sussex, and recently Fudan University in Shanghai. It conducts research on the interdisciplinary aspects of climate change and is committed to promote informed and effective dialogue across society about the options to manage our future climate.