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Ecuador currently does not have any scientifically designed wildfire potential index. Therefore, an alternative approach was to use an international index suitable for this region. The McArthur Forest Fire Danger Index is commonly used in Australia. This index uses daily values of maximum temperature, relative humidity and wind speed. The index also incorporates a drought factor. This factor represents moisture in soil. This is indirect measure of the wildfire fuel availability. This empirical index is valid for the Southeastern forest ecosystem of Australia. In this wildfire-prone ecosystem, the eucalyptus is the dominant vegetation. Latin-America experienced a massive introduction of this specie. This occurred for commercial purposes in the early years of the 19th century. Thus, is reasonable to expect that this index may represent the Ecuadorian wildfire potential.   Using The application of  this indexdaily values were computed  with weather station and reanalysis data. data yielded daily values.  With weather station data the calculation comprised the period 1997-2012. The bias-corrected reanalysis data allowed to extend the method for the period 1961-2012. For each year, a sum of the daily FFDI valuesduring the wildfire season July-August-September (JAS)  provided a seasonal metric of wildfire potential. This cumulative FFDI corresponds to the wildfire season July-August-September (JAS).  Finally, we calculated the 85th percentile on the seasonal FFDI time series. This determined which were extreme wildfire seasons during the period 1961-2012. \subsubsection{Investigation of ENSO influence over wildfire seasons}    Two approaches drove the investigation of ENSO's link over wildfire seasons. Firstly, it was important to know the influence of ENSO in the months leading the wildfire season JAS. Thus, we calculated  linear correlations of seasonal averages of SOI and Nino 3.4 ENSO indices  withJAS  FFDI values allowed to establish this relationship. values.  This averages comprised three-months seasons starting from October-November-December (OND) of the previous year. The correlation included the SOI and Nino 3.4 values for the concurrent JAS season. A second approach compared the extreme wildfire seasons with ENSO's categories of intensity. We used the categories proposed by the National Oceanic and Atmospheric Administration (NOAA). \section{Results}