MODIS Collection 5 Active Fire Product User's Guide Version ... - FAO

4.3 MOD14A2 and MYD14A2The MOD14A2 (Terra) and MYD14A2 (Aqua) daily Level 3 8-day summary fire products are tilebased,with each product file spanning one of the 460 MODIS tiles, 326 of which contain landpixels. The product is a 1-km gridded composite of fire pixels detected in each grid cell over each8-day compositing period.4.3.1 Fire MaskThe fire mask is stored as a 1200 × 1200 8-bit unsigned integer SDS named “FireMask”. (Forhistorical reasons this layer was named “most confident detected fire” prior to Collection 5.) Thissummary fire mask is a maximum value composite of the Level 2 fire product pixel classes (Table 2)for those swaths overlapping the MODIS tile during the eight-day compositing period.4.3.2 QAThe QA layer contains pixel-level quality assessment information stored in a 1200 × 1200 8-bitunsigned integer image. As with the MOD14A1 and MYD14A1 products, only three unique values(0, 1, or 2) are possible (see Table 5).4.3.3 Level 3 Tile NavigationForward and inverse mapping of the MODIS sinusoidal tile grid used for the MOD14A2 andMYD14A2 products is the same as for the MOD14A1 and MYD14A1 products. See Section 4.2.6for details.4.3.4 Example CodeExample 4: MATLAB code to read the Level 3 MODIS 8-day fire mask, using the MATLAB routinehdfread. This is probably the easiest way to read individual HDF SDSs in MATLAB.mod14a2_file = ’MYD14A2.A2004193.h08v08.005.2007207151726.hdf’% read entire "FireMask" SDS in one shotfire_mask = hdfread(mod14a2_file, ’FireMask’);% display fire mask (transposed so that North appears on top)imagesc(fire_mask’);27