A GIS-based approach for tornado risk assessment in Mexico

Tornadoes are considered the most extreme manifestation of severe weather, and they are classified as a potentially disastrous phenomenon. In Mexico, tornadoes are common, but they have not received particular attention until recent years because of the socioeconomic impacts derived from significant events. Tornadoes are one of the few natural phenomena in Mexico that do not have an associated risk mapping, as is already the case for other meteorological threats. The present investigation aims to fill this gap by introducing a tornado risk assessment in Mexico using a GIS-based approach. To this end, the risk components—hazard, vulnerability, and exposure—are examined. Tornado hazard was calculated by combining historical tornado reports with potentially severe convective environments computed from the ERA5 dataset. Tornado vulnerability was addressed by the construction of socioeconomic indicators and a multivariate statistical method application. The resulting values were used to define a weighted index based on five main driving factors affecting vulnerability. Exposure was determined using population density. Every subsequent index was added at the municipality level and allowed the computation of a Tornado Risk Index. The results show diverse spatial patterns associated with the three risk components and the risk itself. This first attempt to assess the tornado risk in Mexico exposes relevant information about the natural phenomena and the societal components based on vulnerability and exposure effects. The results can be used to support diverse programs related to integrated risk management for tornadoes in Mexico.