Technical note: comparison of methods for threshold selection for extreme sea levels. Issue 2 (22nd February 2017)

• Record Type: Journal Article
• Authors: Caballero‐Megido, C.; Hillier, J.; Wyncoll, D.; Bosher, L.; Gouldby, B.
• Is Part Of: Journal of flood risk management. Volume 11:Issue 2(2018)
• Page Start: 127
• Page End: 140
• Publication Date: 2017-02-22
• Subjects: Coastal -- extreme events -- extreme value statistics -- storm surge; Flood control -- Periodicals; Floods -- Risk assessment -- Periodicals; Flood damage prevention -- Periodicals; Flood warning systems -- Periodicals; 627.405
• DOI: 10.1111/jfr3.12296
• Languages: English
• ISSNs: 1753-318X

Abstract

Abstract : Extreme value analysis is an important tool for studying coastal flood risk, but requires the estimation of a threshold to define an 'extreme', which is traditionally undertaken visually. Such subjective judgement is not accurately reproducible, so recently a number of quantitative approaches have been proposed. This paper therefore reviews existing methods, illustrated with coastal tide‐gauge data and the Generalized Pareto Distribution, and proposes a new automated method that mimics the enduringly popular visual inspection method. In total, five different types of statistical threshold selection and their variants are evaluated by comparison to manually derived thresholds, demonstrating that the new method is a useful, complementary tool.