windrose: Plot a Wind Rose

In ropensci/clifro: Easily Download and Visualise Climate Data from CliFlo

Plot a Wind Rose

Description

Plot a wind rose showing the wind speed and direction for given facets using ggplot2.

Usage

windrose(
  speed,
  direction,
  facet,
  n_directions = 12,
  n_speeds = 5,
  speed_cuts = NA,
  col_pal = "GnBu",
  ggtheme = c("grey", "gray", "bw", "linedraw", "light", "minimal", "classic"),
  legend_title = "Wind Speed",
  calm_wind = 0,
  variable_wind = 990,
  n_col = 1,
  ...
)

Arguments

speed	numeric vector of wind speeds.
direction	numeric vector of wind directions.
facet	character or factor vector of the facets used to plot the various wind roses.
n_directions	the number of direction bins to plot (petals on the rose). The number of directions defaults to 12.
n_speeds	the number of equally spaced wind speed bins to plot. This is used if speed_cuts is NA (default 5).
speed_cuts	numeric vector containing the cut points for the wind speed intervals, or NA (default).
col_pal	character string indicating the name of the RColorBrewer colour palette to be used for plotting, see 'Theme Selection' below.
ggtheme	character string (partially) matching the ggtheme to be used for plotting, see 'Theme Selection' below.
legend_title	character string to be used for the legend title.
calm_wind	the direction of wind that is considered calm. Following convention of the National Weather Service, winds with a direction of 0 are considered calm by default.
variable_wind	numeric code for variable winds (if applicable).
n_col	The number of columns of plots (default 1).
...	further arguments passed to theme.

Details

This is intended to be used as a stand-alone function for any wind dataset. A different wind rose is plotted for each level of the faceting variable which is coerced to a factor if necessary. The facets will generally be the station where the data were collected, seasons or dates. Currently only one faceting variable is allowed and is passed to facet_wrap with the formula ~facet.

Note that calm winds are excluded from the wind rose.

Value

a ggplot object.

Theme Selection

For black and white wind roses that may be preferred if plots are to be used in journal articles for example, recommended ggthemes are 'bw', 'linedraw', 'minimal' or 'classic' and the col_pal should be 'Greys'. Otherwise, any of the sequential RColorBrewer colour palettes are recommended for colour plots.

See Also

theme for more possible arguments to pass to windrose.

Examples

# Create some dummy wind data with predominant south to westerly winds, and
# occasional yet higher wind speeds from the NE (not too dissimilar to
# Auckland).

wind_df = data.frame(wind_speeds = c(rweibull(80, 2, 4), rweibull(20, 3, 9)),
                     wind_dirs = c(rnorm(80, 135, 55), rnorm(20, 315, 35)) %% 360,
                     station = rep(rep(c("Station A", "Station B"), 2),
                                   rep(c(40, 10), each = 2)))

# Plot a simple wind rose using all the defaults, ignoring any facet variable
with(wind_df, windrose(wind_speeds, wind_dirs))

# Create custom speed bins, add a legend title, and change to a B&W theme
with(wind_df, windrose(wind_speeds, wind_dirs,
                       speed_cuts = c(3, 6, 9, 12),
                       legend_title = "Wind Speed\n(m/s)",
                       legend.title.align = .5,
                       ggtheme = "bw",
                       col_pal = "Greys"))

# Note that underscore-separated arguments come from the windrose method, and
# period-separated arguments come from ggplot2::theme().

# Include a facet variable with one level
with(wind_df, windrose(wind_speeds, wind_dirs, "Artificial Auckland Wind"))

# Plot a windrose for each level of the facet variable (each station)
with(wind_df, windrose(wind_speeds, wind_dirs, station, n_col = 2))

## Not run: 
# Save the plot as a png to the current working directory
library(ggplot2)
ggsave("my_windrose.png")

## End(Not run)

ropensci/clifro documentation built on Feb. 11, 2025, 10:34 p.m.