Fires in Portugal on 15th October 2017: a catastrophic evolution

Abstract

In 2017 Portugal mainland was affected by two events with major forest fires, that caused a large number of casualties and extensive property loss. Both events happened outside the typical forest fire season, which goes between July 1st to September 30th. Severe drought since the early spring 2017 and extreme heat in the summer are factors that may lead enhance the size, severity and spread rate of forest fires (Pereira et al, 2015). On October 15th, a number of factors joined together simultaneously: very low humidity in both the boundary layer and cumulated biomass (Gouveia et al., 2012), unseasonably high temperatures and a tropical cyclone (Ophelia) located to the west of Iberia, enhancing a south-easterly flow over mainland Portugal. The combination of these factors leads to a record number of forest fires in a single day with serious consequences, including the loss of lives and property.