Avaliação dos riscos de ocorrência de incêndios florestais nas regiões Norte e Noroeste da Amazônia Matogrossense

The State of Mato Grosso is considered an important agricultural frontier in Brazil and has high rates and a large spatial variability of hotspots, with economic, ecological and landscape losses. Evaluated the performance of risk indices of forest fire obtained by Formula Monte Alegre (FMA) and Formula Monte Alegre Amended (FMA+) in the municipalities of Campo Novo dos Parecis, Cotriguacu, Juara, Juina, Nova Maringa, Nova Ubirata, Novo Mundo, Sinop and Sorriso, in Mato Grosso, Brazil. The daily data of air temperature, relative humidity, wind speed and rainfall obtained from automatic weather stations managed by the National Institute of Meteorology. In evaluating the two methods we used the values of relative humidity measured at 13:00h and minimum daily value. Proposed correlations between the number of hotspots recorded by the system NOAA/AVHRR and the number of days in months classified as high risk and very high (FMA>8.1 and FMA+ > 14.1). The months of July and August were above 90% of days classified as very critical (very high risk). The index FMA+ with the wind speed and relative humidity at 13:00 h possible overestimation of less than 1.0 hotspot month, with adjustments for 98.69% and an overall performance of 86.44%, the method most recommended to assess the risk of fire in the North and Northwest of the State of Mato Grosso.