At the beginning of the MTBS project (2006), Landsat imagery was not freely available and the project could not purchase more than two Landsat scenes per year for any path/row. Consequently, ideal imagery was not always used to map each fire. Image selection was often a compromise between optimum phenology and the number of fires that could be mapped.
In 2008, the Landsat archive was opened for free data distribution and in 2009 the project reviewed the scene selections for 626 fires greater than 15,000 acres. Of these, 81 fires were revised using the best available imagery. When necessary, immediate post fire imagery was also obtained to improve perimeter delineation. Those revisions were released several years ago. Recently, a similar review was conducted for 343 fires between 10,000 and 15,000 acres that were mapped prior to opening the Landsat archive. Those fires will be available for a future data release. For the long term, MTBS intends to review fires between 5,000 and 10,000 acres and possibly all fires down to the minimum mapping size: 1000 acres in the west and 500 acres in the east. The "What's New" page will be updated as these revisions are released.