FPAR 16-day 0.25° dataset tiled by vegetation type (preliminary)

The global 16day, 0.01° FAPAR product from the two-stream inversion package (TIP, Pinty et al. 2011a, Pinty et al 2011b) in conjunction with a global high resolution land use map from MODIS (Friedl et al 2010) was used to generate global 16 day and 0.25° resolution FAPAR datasets for each vegetation type. TIP assimilates albedos from MODIS in the visible and near infrared domain into a radiative transfer model. The TIP product was screened for good quality data and aggregated to 0.25° for each vegetation type and time step. The following IGBP vegetation types are considered: evergreen boradleaved forest, evergreen needle-leaved forest, deciduous broadleaved forest, deciduous needle-leaved forest, mixed forest, woody savannas, savannas, closed shrubland, open shrubland, grassland, cropland, cropland natural vegetation mosaic. Grasslands and croplands were further separeted into C3 and C4 photosynthetic pathway using ancillary datasets (Winslow et al 2003, Monfreda et al 2008). Long systematic gaps (e.g. due to polar night or periodic snow cover in northern high latitudes in winter) were filled with random data from the lower 0.2 quantile of the time series. Remaining gaps are filled based on an iterative SSA (Singular Spectrum Analysis) scheme (Kondrashov and Ghil, 2006), which detects periodic components in the signal to interpolate gap values