New reported wildfires for each day are put onto a grid 80 km x 80 km using the discovery date.
If one or more wildfires occur in a grid box three days before through three days after the valid date, that box is assigned the value "1" for the day. If no wildfires occur, it's a zero.
The raw frequency for each day at each grid location is found for the period (number of "1" values divided by number of years) to get a raw annual cycle.
The smoothed time series are then smoothed in space with a 2-D Gaussian filter (40 km in each direction).