fasstr (version 0.5.3)

add_basin_area: Add a basin area column to daily flows

Description

Add a column of basin areas to a daily streamflow data set, in units of square kilometres.

Usage

add_basin_area(data, groups = STATION_NUMBER, station_number, basin_area)

Value

A tibble data frame of the original source data with an additional column:

Basin_Area_sqkm

area of upstream drainage basin area, in square kilometres

Arguments

data

Data frame of daily data that contains columns of dates, flow values, and (optional) groups (e.g. station numbers). Leave blank or set to NULL if using station_number argument.

groups

Name of column in data that contains unique identifiers for different data sets, if applicable. Only required if groups column name is not 'STATION_NUMBER'. Function will automatically group by a column named 'STATION_NUMBER' if present. Remove the 'STATION_NUMBER' column beforehand to remove this grouping. Leave blank if using station_number argument.

station_number

Character string vector of seven digit Water Survey of Canada station numbers (e.g. "08NM116") of which to extract daily streamflow data from a HYDAT database. Requires tidyhydat package and a HYDAT database. Leave blank if using data argument.

basin_area

Upstream drainage basin area, in square kilometres, to apply to observations. Three options:

(1) Leave blank if groups is STATION_NUMBER with HYDAT station numbers to extract basin areas from HYDAT.

(2) A single numeric value to apply to all observations.

(3) List each basin area for each group/station in groups (can override HYDAT value if listed) as such c("08NM116" = 795, "08NM242" = 10). If group is not listed the HYDAT area will be applied if it exists, otherwise it will be NA.

Examples

# Run if HYDAT database has been downloaded (using tidyhydat::download_hydat())
if (file.exists(tidyhydat::hy_downloaded_db())) {

# Add the HYDAT basin area to a data frame with station numbers
flow_data <- tidyhydat::hy_daily_flows(station_number = "08NM116")
add_basin_area(data = flow_data)

# Add the HYDAT basin area to data from HYDAT
add_basin_area(station_number = "08NM116")

# Set a custom basin area
add_basin_area(station_number = "08NM116",
               basin_area = 800)
               
# Set multiple custom basin areas for multiple stations
add_basin_area(station_number = c("08NM116", "08NM242"),
               basin_area = c("08NM116" = 800, "08NM242" = 10))

}