Frequently Asked Questions (FAQs)
Q. Does the sensor problem with Landsat 7 affect LANDFIRE mapping?
LANDFIRE vegetation and fuel mapping relied on circa-2001 Landsat imagery. The Landsat scan line corrector problem occurred in late 2003, after the acquisition of all imagery used in LANDFIRE National (LF c2001).
LF Disturbance mapping used the following imagery to identify changes to the landscape post LF c2001:
|5||1999 - 2008|
|5 and 7 || 2009 - 2010|
|5 || 2011|
|7 || 2012|
Landsat 7 SLC-off imagery were used for MTBS fire mapping and MTBS data was included in LF 2008, LF 2010, and LF 2012. Landsat 7 SLC-off imagery has scan line issues. For LF 2012, these issues were addressed
, however, they were not corrected in LF 2008 and LF 2010.
To reduce the impact of the scan line artifacts in LF 2012 data products caused by gaps in MTBS data, a combination of modeling and image processing techniques were applied. Decision-tree modeling was implemented when appropriate image data were available. A majority focal filling raster image processing technique with a 12 x 12 filter was used when suitable imagery was unavailable. The disturbance legend was modified to account for the additional processing methods so users can identify the source for each disturbed pixel.