Title: | Applies Drainage Area Ratio Method With Correction Factors |
---|---|
Description: | Applies empircally derived parameters for drainage area ratio calculated streamflows in Texas. |
Authors: | Michal Schramm [aut, cre] |
Maintainer: | Michal Schramm <[email protected]> |
License: | GPL-3 |
Version: | 0.1.0 |
Built: | 2024-10-06 02:47:20 UTC |
Source: | https://github.com/mps9506/dartx |
Streamflows estimated using the drainage-area ratio method are typically over- or under-estimated at the tails of the streamflow distribution. Asquith, Roussel, and Vrabel (2006) provide empirically-derived correction factors for estimating streamflows in Texas using the drainage-area ratio method. Applying this function to a dataframe of streamflows will return a dataframe with the original streamflow, the non-exceedance probability (cume_dist), the correction factor used (exp), and the estimated streamflow (Q).
dartx(.data, flow, dar, defaultPhi = TRUE, ...)
dartx(.data, flow, dar, defaultPhi = TRUE, ...)
.data |
table of class data.frame with at least one column with streamflows |
flow |
Variable specifying streamflows in df |
dar |
numeric, drainage area ratio to be applied |
defaultPhi |
logical. Defaults to |
... |
optional arguments. If |
The drainage area ratio is an algebraic method for estimating same-day streamflows from one location to another on the basis the the ratio of the drainage areas are the same as the ratio of the streamflow. The typical equation is:
Where is the streamflow at the ungaged site,
is the streamflow
at the gaged site,
and
are drainage areas of
and
. Often,
is assumed equal to one.
Asquith, Roussel, and Vrabel (2006) developed empirically derived values
of based on streamflow percentiles (non-exceedance probability)
for 54 percentiles of daily mean streamflow in Texas. Values of
range from 0.700 to 0.935.
dataframe with new variables: Q_percentile, exp and Q. Where Q_percentile are the non-exceedance probability, exp are the values of phi applied to the DAR calculation and Q is the DAR estimated flow value.
Asquith, William H., Meghan C. Roussel, and Joseph Vrabel. 2006. “Statewide Analysis of the Drainage-Area Ratio Method for 34 Streamflow Percentile Ranges in Texas.” 2006–5286. U.S. Geological Survey Scientfic Investigations Report. U.S. Geological Survey. https://pubs.usgs.gov/sir/2006/5286/pdf/sir2006-5286.pdf.
Mean values of phi per quartile for stations < 100 miles apart and absolute value of the logarithim of the ratio fo the drainage areas >= 0.25. Included mainly to demonstrate how to use custom Phi values.
quartilePhi
quartilePhi
A data frame with four rows and three variables:
minimum of the range of streamflow percentile values that exp is used for
minimum of the range of streamflow percentile values that exp is used for
estimated values of the exponent parameter to apply to the drainage area ratio
Asquith, William H., Meghan C. Roussel, and Joseph Vrabel. 2006. “Statewide Analysis of the Drainage-Area Ratio Method for 34 Streamflow Percentile Ranges in Texas.” 2006–5286. U.S. Geological Survey Scientfic Investigations Report. U.S. Geological Survey.