Adds isopycnal lines to an existing temperature-salinity plot. This is
called by plotTS(), and may be called by the user also, e.g. if
an image plot is used to show TS data density.
drawIsopycnals(
nlevels = 6,
levels,
rotate = TRUE,
rho1000 = FALSE,
digits = 2,
eos = getOption("oceEOS", default = "gsw"),
trimIsopycnals = TRUE,
cex = 0.75 * par("cex"),
col = "darkgray",
lwd = par("lwd"),
lty = par("lty")
)None.
suggested number of density levels (i.e. isopycnal curves);
ignored if levels is supplied. If this is set to 0, no isopycnal
are drawn (see also levels, next).
optional density levels to draw. If this is NULL, then
no isopycnals are drawn.
boolean, set to TRUE to write all density labels
horizontally.
boolean, set to TRUE to write isopycnal labels as e.g.
1024 instead of 24.
number of decimal digits to use in label (supplied to
round()).
equation of state to be used, either "unesco" or
"gsw".
logical value (TRUE by default) that
indicates whether to trim isopycnal curves (if drawn)
to the region of temperature-salinity space for which density
computations are considered to be valid in the context of the
chosen eos; see the “Details” of the documentation
for plotTS().
size for labels.
color for lines and labels.
line width for isopycnal curves
line type for isopycnal curves
Dan Kelley
Fofonoff, N. P., and R. C. Millard.
"Algorithms for Computation of Fundamental Properties of Seawater."
UNESCO Technical Papers in Marine Research. SCOR working group on Evaluation of CTD data;
UNESCO/ICES/SCOR/IAPSO Joint Panel on Oceanographic Tables and Standards, 1983.
https://unesdoc.unesco.org/ark:/48223/pf0000059832.
McDougall, Trevor J., David R. Jackett, Daniel G. Wright, and Rainer Feistel.
"Accurate and Computationally Efficient Algorithms for Potential Temperature and Density of Seawater."
Journal of Atmospheric and Oceanic Technology 20, no. 5 (May 1, 2003): 730-41.
https://journals.ametsoc.org/jtech/article/20/5/730/2543/Accurate-and-Computationally-Efficient-Algorithms.
plotTS(), which calls this.