This package contains functions that are useful in data pre-processing and evaluation tasks for exploring performance of the National Water Model streamflow data, especially under low-flow and drought conditions. An example of an evaluation workflow is described below:
Function | Function Description -------- | -------------------- hourly2DailyQ | Reads in hourly NWM streamflow data from a NetCDF format and aggregates to a daily timestep (computes the average). This function runs through a directory that contains individual hourly files for a single year, and the folder must be named in the format "yyyy" (e.g. 1993). USGSFlowStats | Calculates summary streamflow statistics (min, max, avg) and low flow thresholds (5%, 25%, 7Q10, 7Q2) for a given streamgage and time period. Uses the USGS dataRetrieval package and the PearsonDS package. NWMFlowStats | Calculates summary streamflow statistics (min, max, avg) and low flow thresholds (5%, 25%, 7Q10, 7Q2) for a reach of the NWM. User must the name of the reach (COMID) and specify a .csv file of with a "Date" column and reach columns. Uses the PearsonDS package. retroNWMUSGSEval | Calculates goodness-of-fit (GOF) statistics for NWM and USGS time series on an overall, seasonal, and yearly basis. Statistics calculated are provided for both relative streamflow (streamflow as a percentile of historic streamflow values, calculated on a monthly basis) and absolute streamflow (average daily streamflow). lowFlowEval | Calculates the number of low flow events on a monthly basis over the period of record for both NWM historic data and USGS historic data. Returns a summary of the differences, as well as plots of the number of low flow events and differences in low flow events. NHDSubset | Subsets the streamflow reaches (from a geodatabase of the NHDPlus Stream Network) based on Hydrologic Disturbance Index, Stream Order, and State
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.