syntheticdv2lff, Scripts for low-flow frequency (LFF) estimation (and bias correction) from daily mean streamflow estimated at level-12 hydrologic unit code (HUC12) pour points in the southeastern United States

The syntheticdv2lff repository contains R language source code that document the workflow to compute low-streamflow (low-flow) frequency (LFF) statistics from previously estimated streamflow at level-12 hydrologic unit code (HUC12) pour points (watershed outlet locations) in the south-central and southeastern United States for 1950 through 2010 and associated bias correction. LFF statistics computed from synthetic streamflow are compared to LFF statistics computed from daily mean streamflow for 427 U.S. Geological Survey streamflow-gaging stations that are hydrologically matched to (coincident with) a HUC12 pour point. Conventional methods of frequency analyses are made using the annual minima: (1) the minima are assumed to be distributed as three-parameter log-Pearson type III, and (2) a moment-like method for parameter estimation. The difference between the synthetic and gaged LFF statistics were used to investigate a bias. The organization is such that the greater workflow is designed to run-out-of-the box so that interested readers can readily evaluate and otherwise test the veracity of the algorithms herein. The repository creates output data structures that support a companion paper and data releases complimentary to this repository (in review). The practical applications of the output data structures are outside the scope of the repository but are addressed in a companion paper.