Analysis of wind damages during 2009-2018 period in Basque Country

Severe  weather  phenomena  impact  the  European  society  and economy  in  many  ways,  from disruption  in  various  sectors  and substantial  damages  in  infrastructure  to  human  and  economic losses.  Windstorms are amongst the most damaging natural hazards in Europe, with approximately 5 € billion of estimated annual losses in the EU.

Economic losses from meteo-climatic hazards depend on the nature of the meteo-climatic severe event and on the vulnerability of exposed human assets to the particular hazard. In  this  work  we  focus  on  wind  damages  that  are  produced  when different meteorological conditions  promoted  high wind gust that affect human assets in a particular area.

In the Basque Country, wind impact episodes can occur during all the year, on one hand during summer session related with severe storms and coastal trapped disturbance and on the other during winter period mainly related with relatively deep pressure system affecting the territory. The latter are by far the ones that generate the events with the greatest impact, both in terms of their spatial extension and the amount of damage generated.

Here we present a characterization study of economic losses in Basque Country due to high impact wind events during a ten years period from 2009 to 2018. For this purpose we analyzed the “non-typical cyclonic storm”   damage   data   provided   by   the Spanish   Insurance Compensation Consortium (CCS) for the Basque Country area. 71.846 accepted claims corresponding to 189 days, affecting 251 municipalities, with a total amount of 83.6 million euros for the ten years period studied. We analyzed those data considering their typology and their spatial and temporal distribution. In order to extract some useful conclusions for further impact modeling, we include surface wind characteristics registered in the Automatic Weather Station (AWS)  Basque network. The final objective of this study is  to  contribute  in  reducing  the  knowledge  gaps  at  the  interface  between  available  local wind prediction/analysis systems and impact observed in Basque Country as a consequence of wind severe events.

The damages are distributed in 93 episodes, made up of one or more consecutive days with paid claims. The 21 high-impact episodes (more than 50 claims) account for 43% of the days with 99% of the claims and damages. In the 10 days of extreme impact (more than 1000 claims), which represent 5% of the days, 90% of the claims and 89% of the damages are recorded. The seasonal distribution of damage shows a clear winter pattern. Although the damage are produced throughout the territory, with different degree of impact in nearly all the municipalities,  there is a certain concentration in the three Basque capitals with 22% of the claims and 23% of the economic losses.