According to research by the environmental organisation ZERO, comparative figures for the period 1 August to 15 September from 2011 and 2016, “this year has seen by the far the highest levels of air pollution in Portugal.”
Estarreja, Vouzela, Funchal, Ílhavo and Montemor-o-Velho, areas which were all affected by severe forest fires, were also those to record the highest levels of pollution.
ZERO adds that in addition to the forest fires, strong southerly winds this summer, bringing with them dust from the Sahara, also contributed to the diminished air quality.