A Relationship Between Rainfall and Burned Area for Portugal

Abstract

Total area burned yearly in Portugal in the period of 1975 to 1992 is related to rainfall during particular periods of the year. Precipitation in the period of January to April, corresponding to Winter and early Spring, related to fine fuel growth and to the water reserve in the soil, shows a non monotonic relationship with burned area each year, due to the conflicting mechanisms of the these two processes. Rainfall between June and September, corresponding to the main fire season in Portugal, exhibits an inverse relation with burned area. Data of a single weather station were used in the analysis and it was demonstrated that they are representative of a wide area in the country.