beale: Calculate pollutant loads by means of the Beale Ratio...

In smwesten-usgs/autobeale-R: autobeale: code to calculate loads by means of Beale's Ratio Estimator.

Description

This function is an R implementation of the code originally written in Fortran. The Beale Ratio Estimator has been shown to provide an unbiased load estimate.

Usage

beale(discharge_cms, concentration_mg_L)

Arguments

discharge_cms	vector of daily discharge values given in cubic meters per second.
concentration_mg_L	paired vector of daily concentration values given in mg_L

Details

Peter Richards, one of the authors of the Fortran implementation, describes it this way:

"The Beale Ratio Estimator is described in Tin (1965). It has been widely used for computation of substance loadings to receiving waters, particularly in the Great Lakes system. The initial code was developed by Ken Baun of Wisconsin DNR (1982). It was subsequently used and developed by Kevin McGunagle at the International Joint Commission (IJC), from whom the current version was received. It was then developed in the 1990<e2><80><99>s by Pete Richards at the National Center for Water Quality Research at Heidelberg University (www.heidelberg.edu/academiclife/distinctive/ncwqr). Peter developed the code to work with the Macintosh computer of the time (<e2><80><9c>Motorola" architecture, which was replaced by Intel architecture ca. 2005), and included a Graphic User Interface (GUI) and an algorithm that objectively and sequentially searched out the best stratification given the data, with <e2><80><9c>best<e2><80><9d> being defined as minimizing the root-mean-square error (RMSE) given the data at hand. This is the current and final version. A Windows version of the code was also developed, with a minimal GUI."

Value

A list with the following items:

Name	Description
load_total_corrected	bias-corrected load for entire period of calculation
load_daily_corrected	bias-corrected daily load
load_mean_daily	mean of daily loads over period of calculation
load_daily	vector of individual daily loads
confidence_interval	95% confidence interval about the total corrected load
discharge_mean	mean discharge during calculation period
discharge_mean_sample_days_only	mean discharge, including only days for which concentration data exist
mse	mean squared error
rmse	root mean square of errors
df	number of degrees of freedom
n_conc	number of concentration data points used in calculation
n_discharge	number of discharge values used in calculation

Examples

library(dplyr)
discharge_data <- read.table("ROCKFLOW.DAT", header=TRUE )
concentration_data <- read.table("ROCKNO3.DAT", header=TRUE )
flow_conc_df <- left_join(discharge_data, concentration_data, by=c("date" = "date") )
head( flow_conc_df )
beale( discharge_cms=cfs_to_cms( flow_conc_df$discharge ), concentration_mg_L=flow_conc_df$concentration )

smwesten-usgs/autobeale-R documentation built on May 30, 2019, 5:04 a.m.