Multi-Hazard Risk Assessment on La Palma: Building Resilience through Insights from Past and Future Impacts

The 2021 Tajogaite eruption of the Cumbre Vieja volcano, is one of the longest and most destructive eruptions recorded on La Palma, Canary Islands. The eruption lasted from September 19 to December 13, 2021, following a 50-year dormancy. This hybrid event was characterized by pulsatory activity, extensive lava flows, tephra fallout, and gas emissions, leading to the evacuation of over 8,000 residents, destruction of more than 2,800 buildings, and significant disruptions to infrastructure and economic sectors, including tourism, agriculture, and energy sectors. This eruption serves as a benchmark for assessing multi-hazard scenarios under current and projected future conditions.

We create a volcanic eruption sequence under current conditions for La Palma based on the previous 2021 eruption by simulating ash dispersal and deposition using Fall3D, a 3D Eulerian model, and lava flows based on the stochastic model MrLavaLoba.

Outputs, such as deposit thickness, ground load, and lava coverage, are integrated with socioeconomic and infrastructure datasets to assess exposure and potential damages with emphasis on the tourism sector. Infrastructure connectivity losses for electricity, water and roads are examined as part of the study.

In addition, the same volcanic eruption is simulated for 2050 under consideration of a preceding drought event on La Palma. This future scenario aims to illustrate the impact past events will have under future climate and socioeconomic conditions, as well as look into the dynamics of exposure and vulnerability along the pathway from 2021 to 2050.

As the quantitative outputs often only tell part of the story, semi-quantitative and qualitative methods are also used including the production of a Tourism Resilience Scorecard using qualitative and semi-quantitative indices.

Our findings underscore the critical need for integrating multi-disciplinary data and stakeholder engagement in developing actionable hazard and resilience strategies in the tourism sector. These scenarios not only deepen our understanding of past events but also provide a roadmap for mitigating future risks in the face of compounding environmental and societal challenges. This work has been completed as part of the MYRIAD-EU Project.