I would like to create a fire frequency map in ArcGIS showing the areas which have burnt 1, 2, 3 times etc (overlapping areas). Currently I have years from 2000 to 2014 of burnt area MODIS data which I have converted into polygons but I'm really struggling to figure out how to do this
There is also the tool "feature to polygons" which will take overlapping polygons and create "flat" polygons from that, which can then be used with their centroid points and a spatial join to the stacked, original polygons to count the number of occurences.
The blog post at http://blogs.esri.com/esri/arcgis/2012/11/13/spaghetti_and_meatballs/ describes this method.
Look at the Overlay toolset, see which works best for you.