plot.ctd {oce}R Documentation

Plot seawater CTD data

Description

Plot a summary diagram for CTD data.

Usage

## S3 method for class 'ctd':
plot(x,ref.lat=NaN, ref.lon=NaN, 
  grid=TRUE, col.grid="lightgray",
  which=1:4, coastline,
  Slim, Tlim, plim, densitylim, dpdtlim, timelim,
  lonlim, latlim,
  latlon.pch=20, latlon.cex=1.5, latlon.col="red",
  ...)

Arguments

x A cdt object, e.g. as read by read.ctd.
ref.lat Latitude of reference point for distance calculation
ref.lon Longitude of reference point for distance calculation
grid Set TRUE to get a grid on all plots.
col.grid The color of the grid.
which list of desired plot types. There are four panels in total, and the desired plots are place in these, in reading order. Which=1 gives a combined profile of temperature and salinity. which=2 gives a combined profile of sigma-theta and N^2. which=3 gives a TS plot. which=4 gives a textual summary of some aspects of the data. which=5 gives a map, with a dot for the station location (note that this requires that a coastline be given). which=6 gives a profile of density and dP/dt (useful for evaluating whether the instrument is dropping properly through the water column). which=7 gives a profile of density and time. which=8 gives a profile of index number (especially useful for ctd.trim).
coastline a coastline object, e.g. as read by read.coastline (ignored if no map plotted).
Slim optional limits of salinity axes
Tlim optional limits of temperature axes
plim optional limits of pressure axes
densitylim optional limits of density axis
dpdtlim optional limits of dP/dt axis
timelim optional limits of delta-time axis
lonlim optional limits of longitude axis of map (ignored if no map plotted)
latlim optional limits of latitude axis of map (ignored if no map plotted)
latlon.pch pch for sample location (ignored if no map plotted)
latlon.cex cex for sample location (ignored if no map plotted)
latlon.col col for sample location (ignored if no map plotted)
... optional arguments passed to plotting functions. A common example is to set df, for use in sw.N2 calculations.

Details

Creates a multi-panel summary plot of data measured in a CTD cast. The panels are controlled by the which argument. Normally, 4 panels are specified with the which, but it can also be useful to specify less than 4 panels, and then to draw other panels after this call.

If only 2 panels are requested, they will be drawn side by side.

If only one panel is drawn, par will not be altered, which means that you may follow this call with other plotting commands, and the results will appear on the plot (which is not the case for the multi-panel forms). This is very useful in trimming the data, e.g. you might do plot(ctd, which=8) and notice that downcast is between index 10 and 300; then try plot(ctd.trim(ctd, "index", 10, 300), which=8) to see if your guess is right, and thus gradually you can find good settings for trimming; see also plot.ctd.scan.

Author(s)

Dan Kelley

See Also

The profiles are plotted with plot.profile, and the TS diagram is plotted with plot.TS. CTD data can be created with as.ctd or read with read.ctd. Summaries of CTD data are provided by summary.ctd.

Examples

library(oce)
data(ctd) 
plot(ctd)

data(coastline.sle)
lonlim <- -(69 + c(52, 41) / 60)
latlim <- 47 + c(48, 58) / 60
plot(ctd, which=c(1,2,3,5),coastline=coastline.sle,lonlim=lonlim,latlim=latlim)

# Trimming
data(ctd.raw)
plot(ctd.raw, which=8)
abline(v=100)
abline(v=120)
abline(v=130)
abline(v=350)
# The range 130 to 350 seems good, but you can narrow in
# by repeating the command below, with differing ranges.
plot(ctd.trim(ctd.raw, "index", 130:350), which=8)
# See results
ctd.trimmed <- ctd.trim(ctd.raw, "index", 130:350)
plot(ctd.trimmed)

[Package oce version 0.1-76 Index]