Future storm surge impacts on insurable losses for the North Sea region

Abstract

Abstract. The influence of climate change on storm surges including increased mean sea level change and the associated insurable losses are assessed for the North Sea basin. In doing so, the newly developed approach couples a dynamical storm surge model with a loss model. The key element of the approach is the generation of a probabilistic storm surge event set. Together with parametrizations of the inland propagation and the coastal protection failure probability this enables the estimation of annual expected losses. The sensitivity to the parametrizations is rather weak except when the assumption of high level of increased mean sea level change is made. Applying this approach to future scenarios shows a substantial increase of insurable losses with respect to the present day. Superimposing different mean sea level changes shows a nonlinear behavior at the country level, as the future storm surge changes are higher for Germany and Denmark. Thus, the study exhibits the necessity to assess the socio-economic impacts of coastal floods by combining the expected sea level rise with storm surge projections.

Identification of storm surge events over the German Bight from atmospheric reanalysis and climate model data

“…Other studies found indications of an increase in storm surge extremes at the North Sea coast associated with increased GHG concentrations (Woth et al, 2006;Langenberg et al, 1999). This is in line with Gaslikova et al (2011), who calculated an increase in insurable losses due to storm surges under future climate scenarios for this region. With respect to wave heights under scenario conditions, Grabemann and Weisse (2008) pointed at increasing extreme wave heights over large parts in the southern and eastern North Sea.…”

Including climate change projections in probabilistic flood risk assessment

“…Pittock et al ., ; Reilly et al ., ; Webster ). Examples of probabilistic climate impact studies exist in several fields, including global crop yields (Tebaldi and Lobell, ), water resource management (New et al ., ; Manning et al ., ), and storm surges (Gaslikova et al ., ). A probabilistic flood risk study is that of Apel et al .…”

“…Pittock et al, 2001;Reilly et al, 2001;Webster 2003). Examples of probabilistic climate impact studies exist in several fields, including global crop yields (Tebaldi and Lobell, 2008), water resource management (New et al, 2007;Manning et al, 2009), and storm surges (Gaslikova et al, 2011). A probabilistic flood risk study is that of Apel et al (2006), in which a simple stochas-tic approach allowing a large number of simulations in a Monte Carlo framework provided the basis for a probabilistic risk assessment for an area of the Rhine (between Cologne and Rees, with a focus on the polder at Mehrum).…”

Estimation of insurance-related losses resulting from coastal flooding in France

“…Sousounis and Kafali (2010) have used the AIR model in a recent study to estimate the potential cost of the 1959 typhoon in Japan. Some models use a probabilistic approach, like Gaslikova et al (2011), for the consideration of future storm surge impact in the North Sea region. The approach of Czajkowski et al (2013) presents a methodology to determine premiums on the basis of property exposure to coastal flood risk.…”