colors dataset is a list containing vectors of colour-scheme
names, e.g. colors$viridis holds colours for the colour palette known
as Viridis, which in 2015 became the default colour palette in the
matplotlib 2.0 Python library [1].
oceColorsViridis uses this dataset.Other datasets provided with oce: adp,
adv, argo, cm,
coastlineWorld, ctdRaw,
ctd, echosounder,
landsat, lisst,
lobo, met, rsk,
sealevelTuktoyaktuk,
sealevel, section,
topoWorld, wind
Other things related to colors: colormap,
oce.colorsGebco,
oce.colorsTwo