Geohazards in Portugal: a state of the art

Abstract In Portugal, scholarly attention towards geohazards has grown significantly since the 1980s, with various analytical methods employed to study these phenomena, including physically-based models, data-driven models, and heuristic techniques. The published research has contributed to a better understanding of the underlying processes, but also includes the assessment of susceptibility, probability, and magnitude of hazardous events. Some studies have extended into risk analysis, considering exposure, asset valuation, and vulnerability, encompassing both physical and social dimensions. Geohazards are concentrated primarily in the western and southern coastal areas of mainland Portugal, particularly in regions like Lisbon, the Lower Tagus Valley, and the Algarve. These areas face multiple geohazard threats, including earthquakes, tsunamis, coastal erosion, floods, flash floods, and landslides. In the remaining parts of mainland Portugal, the inland North and Centre regions are more prone to landslides and soil erosion, while the Alentejo is comparatively safer but still faces a significant risk of soil erosion, contributing to the threat of desertification. Within the Atlantic islands, Madeira exhibits a notable susceptibility to landslides, flash floods, and coastal erosion, whereas the Azores islands encompass a wide spectrum of geohazards, comprising active volcanoes, earthquakes, tsunamis, landslides, flash floods, and coastal erosion.