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Cumbre Vieja volcano, located in La Palma Island (Canary Islands, Spain), erupted on 19 September 2021. Some papers have been published in the past in which the tsunamis generated by a potential massive landslide due to a collapse of one of the volcano flanks are investigated. However, a potential slide of the lava flow down the island slope has not been considered yet. A numerical model has been applied to simulate the propagation of the tsunami generated by such slide and to assess its consequences in the near field (Canary Islands and west coast of Africa). The model provides maps of maximum wave heights and arrival times of the tsunami, as well as time series of water surface elevation at several selected locations. Since the volume involved in such potential slide is a priori not known, several values were tested and their effects compared. [ABSTRACT FROM AUTHOR]

Volcanic areas create spectacular landscapes that contain a great diversity of geoheritage. The study of this geoheritage enables us to inventory, characterise, protect and manage its geodiversity. The Canary Islands are a group of subtropical active volcanic oceanic islands with a great variety of magma types and eruption dynamics that give rise to a wide diversity of volcanic features and processes. The aim of this paper is to identify, for the first time, the diversity of volcanic geoheritage of the Canary Islands and to appraise the protection thereof. To this end, a geomorphological classification is proposed, taking into account the features and processes directly related to volcanism, such as those resulting from erosion and sedimentary processes. The main findings demonstrate that the volcanic geoheritage of the Canary Islands is extremely varied and that this geodiversity is safeguarded by regional, national and, international protection and management frameworks. Even so, and given the enormous pressure of coastal tourism on the coastlines of the islands, we believe that continuing efforts should be made to conserve and manage their volcanic and non-volcanic geoheritage, so that these places can continue to be enjoyed in the form of geotourism. [ABSTRACT FROM AUTHOR]

Las Angustias River is an ungauged stream in the Caldera de Taburiente National Park (Spain), where frequent intense flash-flood events occur. The aim of this research is to analyze the flood hazard at the Playa de Taburiente. Based on the limited information available (short time-series of daily precipitation), a statistical frequency analysis of 24 h rainfall was completed and the precipitation results were transformed into surface runoff. To determine if the model underestimates the flows that are generated in the basin, the dendro-geomorphological information available was used to calibrate results. The results of the HMS model were significantly lower. At this point, both the rainfall data and the rainfall-runoff model were re-analyzed to maximize the rainfall intensity values and the runoff generated (increasing the CN value for the basin). For the 1997 flood event, a 1250 m³·s-1 flood minimizes the RMSE for the disturbed tree sample; this flow value also clearly exceeds any peak flow derived from the rainfall-runoff analysis. It is only when rainfall intensity and surface runoff are maximized that the peak flows obtained approximate those associated with dendro-geomorphological data. The results highlight the difficulties of flood hazard management in ungauged torrential basins in mountain recreational areas (such as National Parks). Thus, in the absence of flow records, when considering the maximum rainfall intensity scenario may be a useful and effective tool for flood risk management. [ABSTRACT FROM AUTHOR]

This study explores the spatiotemporal variability of extreme wave storms around the Canary archipelago, with special focus on the southern coastal flank of Tenerife island, a strategic beach tourism destination of large socioeconomic importance. To this end, experimental and simulated data of winds and waves are used to study the severity, seasonality, and directionality of wave storms with considerable potential to cause significant impact on beaches. Furthermore, tidal experimental records are employed to test the joint occurrence of wave storms and significantly high sea levels. Long-term statistical analysis of extreme wave storms at different locations reveals a complex spatial pattern of wave storminess around the islands and in the southern flank of Tenerife, due to the intricacy of the coastline geometry, the presence of deep channels between islands, the high altitude and complex topography of the islands, and the sheltering effects exerted by each island over the others, depending on the directionality of the incident wave fields. In particular, south of Tenerife, the energy content and directionality of wave storms show substantial spatial variability, while the timing of extreme wave storms throughout the year exhibits a marked seasonal character. A specific extreme storm is examined in detail, as an illustrative case study of severe beach erosion and infrastructure damage. [ABSTRACT FROM AUTHOR]

The analysis of the historical documentary sources together with evidence from the geological record is essential to understand the impact and processes triggered by tsunamis on the Canary Islands. This archipelago has been affected by tsunamis caused by different geological processes, of which the most studied have been those generated by prehistoric mega-landslides. However, there is also evidence of those produced by distant tsunamigenic sources. An exhaustive review of all documentation available was made, identifying the existence of at least four seismically triggered tsunami episodes (1755, 1761, 1941 and 1969), the majority with an epicenter in the Azores-Gibraltar boundary. In this work, several tsunamis are cited for the first time, such as the one produced by the Argaga (La Gomera) landslide in 2020. Other episodes historically identified as tsunamis are discarded as they corresponded to other geological events. The effects of most historic tsunamis have gone unnoticed, having occurred in epochs of sparsely populated coastal areas. But their study allows us to infer the need for the archipelago authorities to establish preventive measures to avoid possible damage from tsunamis, especially if we consider the presently high population density of the Canarian littoral. [ABSTRACT FROM AUTHOR]