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Free georeferenced resources
- CRU high-resolution climate grids, including a 10-minute data set of mean monthly surface climate over global land areas, excluding Antarctica
- Landsat imagery, all eight spectral bands (gzipped GeoTIFF). For navigation, you will need to know your path and row. This is much better than the three-band GeoCover circa 1990/2000.
- Tree Species Range Maps for North America (shapefiles)
- PSD Gridded Climate Datasets (NetCDF, you will need special software to read it)
- LP DAAC Data Pool (MODIS imagery, low-resolution, but obtained regularly, unlike Landsat)