Windstorm loss quantification starts with a deep understanding of the nature of the underlying peril and how this can be translated into the necessary assumptions required to assess risk. While significant advancements have been made in the European windstorms catastrophe model offerings, challenges to better understanding persist. The WRN programme focuses on addressing these challenges and filling in the gaps in our current understanding. Priorities include
Currently there is no consistent catalogue of historical European windstorm events including track and intensity information. For the insurance sector windstorm ‘footprints’ are needed, including the aggregated surface wind gusts. In co-operation with WRN partners work is under way to provide an open-source track catalogue based on a new ensemble of high-resolution windstorm footprints.
European windstorm risk is heavily affected by large-scale climate patterns, in particular the North Atlantic Oscillation (NAO). One major research stream investigates the drivers for strong NAO anomalies and the variability of extreme anomalies. Historical data and regional climate models provide information on both the NAO behaviour and its effects on frequency, intensity and tracks of European windstorms. In particular the climate models provide insight into possible extremes and so-called ‘black swans’ – unpredicted events. These include events such as low pressure of unprecedented depth or windstorms in parts of Europe where they have never occured before in the historical record.
A second research stream is looking into the ‘clustering’ phenomenon. There is high evidence that climate variability influences storm frequency, tracks and intensity for certain phases of climate patterns, such as the NAO. The main goal is to better understand variability and uncertainty in the probability of Europe-wide and regional windstorm losses (single and aggregate) due to climate variability.
Global Climate Models.
We are reaching the limits of what historical records alone can tell us about European windstorm risk. Detailed long-duration historical records are difficult to assemble and not satisfactory when used to estimate the probability of events, in particular for tail risks and extremes. The WRN is at the centre of employing the outputs of a new generation of high-resolution climate models, which can model realistically the distribution and intensities of European windstorms for the current climate and future climates. In particular, climate models provide better understanding of the predictability of seasonal variability of European windstorm activity, as well as providing some information on future windstorm risk.
Date: Jan 01, 2011 | Type: Paper | Attachment: Download File ›
Authors: Brian Owens
Fields: RMS European Windstorm
Summary: Preliminary review of RMS v11 Europe Windstorm Model by Willis Re Analytics
Date: Mar 04, 2010 | Type: Paper | Attachment: Download File ›
Authors: Patrick McSharry A. Lau
Summary: Using aggregated wind power in Ireland, two approaches of multi-step density forecasts are studied which can be obtained from simple iterations so that intensive computations are avoided.
Date: May 27, 2009 | Type: Paper | Attachment: Download File ›
Summary: This WRN Briefing Document provides an overview of the Serial Clustering of Intense European Windstorms paper.
Date: May 26, 2009 | Type: Paper | Attachment: Download File ›
Summary: This paper investigates how clustering of wintertime extra-tropical cyclones depends on the vorticity intensity of the windstorms, and the sampling time period over which storm transits are counted.
Date: Dec 12, 2008 | Type: Presentation | Attachment: Download File ›
Authors: Renato Vitolo
Summary: Poster presentation from the Conference on Teleconnections in the Atmosphere and Oceans
Date: Jul 08, 2008 | Type: Presentation | Attachment: Download File ›
Authors: David Stephenson
Summary: Find out why hydrometeorological hazard events are not independent and what this means for estimates of annual losses, reinstatement premiums etc.
Date: Feb 01, 2007 | Type: Article | Attachment: Download File ›
Authors: Dr Kirsten Mitchell-Wallace - Catastrophe Management Services - Willis, Andrew Mitchell - Catastrophe Management Services - Willis
Summary: Willis' Catastrophe Management Services has produced an in depth, comprehensive report into the most significant event on a pan-European basis since Jeanette in 2002.