Model application and calibration load data for seasonally dynamic total nitrogen and total phosphorus SPARROW models developed for watersheds draining to Washington waters of the Salish Sea, 2005 through 2020

This data release contains two data sets: 1) the model application data for a set of dynamic total nitrogen (TN) and total phosphorus (TP) SPARROW (SPAtially Referenced Regression On Watershed attributes; Schwarz and others, 2006, https://doi.org/10.3133/tm6B3) load models that were developed for watersheds draining to Washington waters of the Salish Sea (Puget Sound region) 2005 through 2020; and 2) the instream TN and TP loads estimated at water-quality stations that serve as calibration targets for those SPARROW models. For a user to reproduce results, the model application data set includes a copy of the SPARROW modeling computer programming code, the input data used to calibrate the models, the SPARROW control files, and the resulting model predictions. The nutrient calibration load estimation data set includes a copy of the WRTDS (Weighted Regressions on Time, Discharge, and Season; Hirsch and De Cicco, 2015, https://doi.org/10.1016/j.envsoft.2015.07.017) and a copy of the Fluxmaster (Schwarz and others, 2006, https://doi.org/10.3133/tm6B3) load estimation computer programming code, the water-quality and streamflow data, the WRTDS and Fluxmaster control files, and the resulting load predictions. The model input data represent information on surface water body and landscape nutrient sources and transport characteristics, and the nutrient load data that were used to calibrate the models. The model output data represent mean seasonal predictions of in-stream total nutrient loads as well as the relative contributions from individual modeled nutrient sources.