get_daymet              Download and crop the 1-km DAYMET v4 daily
                        weather dataset.
get_ghcn_daily          Download and crop the Global Historical Climate
                        Network-Daily data.
get_itrdb               Download the latest version of the ITRDB, and
                        extract given parameters.
get_nass_cdl            Download and crop the NASS Cropland Data Layer.
get_ned                 Download and crop the 1 (~30 meter) or 1/3 (~10
                        meter) arc-second National Elevation Dataset.
get_nhd                 Download and crop the National Hydrography
                        Dataset.
get_nlcd                Download and crop the National Land Cover
                        Database.
get_padus               Download and crop the PAD-US Dataset.
get_ssurgo              Download and crop data from the NRCS SSURGO
                        soils database.
get_wbd                 Download and crop the Watershed Boundary
                        Dataset.
meve                    The boundary of Mesa Verde National Park
plot_nhd                A basic plotting function for NHD data.
replace_null            Replace NULLs
