Evaluation of the Distribution of Heat Spots on the Margins of Federal Highways in the State of Ceará/Brazil

Abstract

The objective of this paper is to evaluate the distribution of heat sources around federal highways in the state of Ceará/Brazil. The analysis was carried out from satellite generated heat sources and meteorological data collected between 2002 and 2018. The results show that hotspots in the state are concentrated in the second half of the year, with 87% of the hotspots being recorded between the months of September and December. The relationship between annual precipitation and the incidence of hotspots is not direct, drier years do not necessarily show more hotspots. In the analyzed period, in years with higher rainfall rates, a greater number of hot spots were observed. It is estimated that the cause is related to greater availability of vegetation for burning, as well as the realization of fires for the preparation of land for planting. On average, 7% of the total number of hotspots in the state are around the roads. In the years analyzed, this percentage varied between 5% and 12%. In the three roads studied (BR 020, BR 116 and BR 222) the areas with the highest risk of forest fires were identified. The meteorological data and the analysis of the results of the Angstron fire risk index confirm that the second semester is the period that presents favorable atmospheric conditions for the ignition and rapid spread of fires in vegetation, mainly inside the state. The coastline, due to the influence of the sea and longer rainfall regime, did not present a high fire risk index. The results may subsidize disaster prevention and mitigation planning involving the dynamics of transportation and forest fires.

Keywords:
hot spots; forest fire risk; Angstron index