Overview of seismic hazard studies in Central America: A comparative analysis of results

We present an overview of seismic hazard studies in Central America, evaluating all the probabilistic seismic hazard studies (PSHA) published at the national and regional scale, as well as an updated model recently developed (Gamboa-Canté et al., 2025). The key factors in the study for obtaining the updated model are the use of a regional earthquake catalog from 1520 to 2020; the implementation of the last seismic zoning for the region, taking into account the change of the subduction angle along the Central America trench; the implementation of the scaling relationships specific to the Central American upper-plate, and the more suitable ground motion models (GMM) for the region identified using local data. We use the updated model as a reference, comparing the results with previous seismic hazard studies. As a general conclusion, we find that seismic hazard studies undertaken over the last 10 years period at regional or national scales point to an increase in the hazard compared to studies in previous periods, with maximum PGA values now reaching around 0.8g–1.0g for a return period of 475 years in the Costa Rica peninsulas and south of Guatemala. The updated seismic hazard map is consistent with the latest local models generated for each country in the region with variability in PGA values of less than 20 %, although there are some local exceptions. The advantage of the updated map is that it reflects the trend of increasing hazard expressed in recent local studies, but it is a regional map, there is no lack of continuity at the borders between countries, as occurs when a regional map is configured from national maps. We suggest that this regional hazard map be used for Central America (Gamboa-Canté et al., 2025) as a reference map for updating the seismic hazard models or seismic codes of the countries.