To what years do the SPARROW model predictions apply?
|Back to Top| In general, the SPARROW model predictions of nutrient sources and loads reflect long-term mean annual nutrient conditions in streams. A statistical procedure is used (see question #8) to ensure that the model predictions reflect long-term hydrologic and water-quality variability during a consistent time period, which produces robust model predictions of nutrient sources and transport processes. The model predictions of the mean annual load for the calibrated model are standardized to the 1992 base year to give an estimate of the mean nutrient load that would have occurred in streams in 1992 if mean annual flow conditions from 1975-2000 had prevailed. (Note that the mean annual nutrient loads were simulated for 2002 to evaluate the robustness of the model predictions to changes in nutrient sources from 1992-2002; see question #10 for details). The use of nutrient measurements from 1975-1995 and flow records for 1975-2000 in the statistical load estimation procedure ensures
