This record describes a series of rasters containing mean monthly total nitrogen, ammonium, and nitrate atmospheric wet deposition. These data were estimated by multiplying together interpolated gridded surfaces of concentration (fNTN) and precipitation (PRISM). The concentration surfaces were produced through inverse distance weighting both the mean monthly ammonium, nitrate, and total nitrogen concentration estimates measured at the NADP monitoring sites (National Atmospheric Deposition Program 2019). The concentration surfaces were interpolated to a 4-km grid (same grid as precipitation) using the IDW R package. Wet deposition was then estimated as the product of the concentration surfaces and monthly precipitation provided by Wolock and McCabe (2018). Nitrogen atmospheric deposition was additionally linked to medium-resolution NHD catchments following the same area-weighting approach described above. These rasters have a 4 kilometer resolution and are in USGS Albers 96 projection Units are in kilograms per square kilometer.
