ctd: Several CTD casts
In jiho/castr: Process CTD casts

A time series of 41 CTD casts collected at the same station over two years, identified by the date of sampling.

ctd

A data frame with 3134 rows and 6 variables:

date: date of sampling
depth: depth, in m, positive towards the bottom
temp: temperature, in degrees Celsius
sal: salinity, in PSU
chla: chlorophyll a concentration estimated through fluorescence, in mg/m^3
sigma: potential density, in kg/m^3 - 1000

head(ctd)
plot_casts <- function(formula, x) {
  plot(formula, data=x, type="n")
  for (day in unique(x$date)) {
    lines(formula, data=subset(x, date==day))
  }
}
plot_casts(-depth ~ temp, ctd)
plot_casts(-depth ~ sal, ctd)
plot_casts(-depth ~ chla, ctd)
plot_casts(-depth ~ sigma, ctd)