How Unusual Was The Storm Surge Season Of 2013-14 in the UK?

Friday, 19 December 2014
Ivan David Haigh1, Matthew Wadey1, Shari L Gallop1, Robert J Nicholls1 and Kevin Horsburgh2, (1)University of Southampton, Southampton, United Kingdom, (2)National Oceanography Center, Liverpool, United Kingdom
When significant coastal flooding occurs along low‐lying, highly populated, and/or developed coastlines, the impacts can be devastating and long lasting with wide ranging social, economic, and environmental consequences. The UK has a long history of severe coastal flooding, with major events including those that occurred in 1607, 1703 and 1953. The problems associated with coastal flooding again reached the forefront during the latest winter of 2013-2014 when the UK experienced a series of very severe events. What is noteworthy about this most recent winter period is the: (1) large number of significantly coastal flooding events occurring one after another over a relatively short period of time; and (2) the large areas of coastline affected. Extreme events are rarely assessed in terms of ‘clustering’, despite the fact this leads to amplified flood damages. The spatial dependence in flood hazard (i.e. simultaneous flooding in multiple locations) is now receiving more attention, motivated by concern from re-insurance, infrastructure reliability and emergency response, but understanding in this area is still limited. In this paper we assess extreme high water events and their temporal clustering and footprint around the UK, using records from the UK national network of 40 tide gauges, the longest of which extends back 100 years. We identify 100 distinct events, during which water levels exceeded the 1 in 5 year return period. We examine these events in detail and assess the coastal flooding that occurred during each event.