To date we are looking at the MCD43B4 data and corresponding BRDF parameters held in MCD43B1 imagery. From the MCD43B4 we extract a medium solar zenith angle per pixel, provided as a range 0-5, 5-10 degrees etc. Is it possible to extract the solar zenith angle that has been used in derivation of BRDF parameters? We want an absolute value per pixel, not a range.

We are using all cloud-free atmosphere-corrected surface reflectances available over a 16 day period to retrieve the best fit, best sampled BRDF model. The input observations are at overpass times for Aqua and Terra. But no, we don’t pass on the exact overpass szns of each input observation that is used. In V004 we provide NBARs (MCD43B4) at the median overpass time for each satellite for that period; in V005 we will only provide one NBAR at local solar noon for that location (which is what we give for albedo in V004 and V005) and it will be to the full degree -not binned into 5 degree bins (which is only done because we are always constrained by how many bits we can archive). You can of course compute average szn for each satellite or local solar noon for each pixel off line, or you can use the MCD43B1 model parameters and provide NBAR at any explicit szn you’d like. There is some sample forward code under tools on our web page to use to compute NBAR. That is probably your best bet if you need view-angle corrected data at some specific time each day.