The floods recorded in the North of Spain in October 2019. A paradigm of compound and multi-hazard event in the framework of climate and environmental change

This contribution shows a multi-disciplinary forensic investigation of the catastrophic flood event that took place in the northern part of Spain between the 22^nd and 23^rd of October 2019. The case study has been selected for three reasons. Besides flash-floods and floods in several parts of the region of interest, the event also recorded windstorms, one tornado, snowfalls, thunderstorms, strong sea surges, and landslides, that made a good paradigm of a compound and multi-hazard event. The second reason is because the event has been analyzed from three approaches. Firstly, the hydrometeorological perspective, which includes monitoring through meteorological radar and observation stations, as well as the consequences on the surface. Second, from the socio-economic perspective, both in terms of economic impact and in terms of social perception, for which a citizen science experiment was designed with the FLOODUP tool and in collaboration with the Museu de la Vida Rural de l'Espluga de Francolí (a museum located in the village the event hit the most). FLOODUP is an App developed to improve the population risk awareness and sensibilization face to climate change, that can be also used to collect information. In this case it was used during the period of home confinement due to the pandemics to collect information about the emergency management and impacts. This part also includes the cascading effects, as well as what the Covid-19 pandemic meant in the difficulty of recovery. A third approach analyzes the early warning, emergency management and recovery, in addition to various human initiatives that were carried out. Finally, the third consideration follows the example of pair-events comparison developed in the framework of the IAHS Panta Rhei hydrological decade 2013- 2022 like (ex: Kreibich et al., 2017). In this case, the October 2019 event is compared with the floods of October 1994, specifically regarding the Francolí basin. Maximum precipitation recorded in this last event was 410 mm between 9 and 11 October, with a maximum discharge of the Francolí River of 900 m³/s in Montblanc. As a consequence of it, 10 bridges were destroyed, 10 people lost their life and more than 230 € millions in damages were produced. On the 2019 event maximum precipitation was of 293 mm between 22 and 23 October, the maximum discharge in Montblanc was of 544 m³/s and 5 people lost their life and damages were above 44 € millions. Finally, the event is contextualised in the flood trend observed in the region due to climate and environmental changes.  The presentation concludes with the discussion on the potential measures of adaptation that have been already applied or could be applied.

This work has been done in the framework of the M-CostAdapt (CTM2017-83655-C2-1&2-R) research project, funded by the Spanish Ministry of Science and Innovation (MICINN-AEI/FEDER, UE).

Reference. Kreibich, H., S. Vorogushyn, J.C.J.H. Aerts, et al. 2017. Adaptation to flood risk – results of international paired flood event studies. Special collection “Avoiding Disasters: Strengthening Societal Resilience to Natural Hazards” in the journal Earth’s Future. Earth’s Future,5,953–965, doi:10.1002/2017EF000606