Hi all,
I believe I was able to get past these errors and use the biophysical processor to calculate LAI (or FAPAR, etc.) using Landsat 8 imagery.
What I had to do was download both the Level 2 and Level 1 Product for the same image (download from Earth Explorer). These were downloaded as .tar archives. I then copied the four total sun and view azimuth files that were present in the Level 1 download .tar folder (the four TIFs ending in “_SZA.tif”, “_SAA.tif”, “_VAA.tif”, “_VZA.tif”), and I pasted them into the Level 2 download .tar folder. I did not need to change the name of these four files. I then copied the information for these four layers in the Level 1 metadata file (ending in “_MTL.txt”), and pasted the information for these four layers into the Level 2 metadata file. This process allowed SNAP to successfully read in the Level 2 .tar archive and it was able to recognize the four new tifs, which loaded in as “vaa”, “vza”, “saa”, and “sza”.
In order for the biophysical processor to work, I had to rename these four layers in the “Product Explorer” Window. I also had to do band math to correctly scale the DN values for these four layers, which required multiplying each input layer by “0.01”, as detailed in the comments by user Shixian at this link: Biophysical Processor Landsat 8 - #14 by florcamg.
Thanks,
Chris
