15 
tudes. Since it may be assumed that upwelling phenomena 
mainly occur within this layer, the vertical movements 
cannot generate appreciable horizontal contrasts in the 
near-surface temperature and salinity distribution 
(ef. Mittelstaedt, 1972). 
Farther south (south of Cap Blanc, 21°N) there is the 
reservoir of upwelling water, at about the same depths 
as in the north, This water, however, is cooler (and 
generally less saline) than the water of the oceanic 
layer above it, This is due to the general large-scale 
meridional doming upward of the thermohaline layering in 
sonnection with an increase of the vertical gradient in 
lower latitudes (cf, Mittelstaedt, 1974), 
50, the 15° isotherm along the Moroccan coast lies at 
a depth of about 200 m, whereas it rises to a depth of 
50 to 100 m in the south (off Mauretania), 
Even though the increasing layering somewhat reduces 
the vertical thickness of upwelling circulation in the 
south, it becomes clear that under these conditions up- 
welling in the lower latitudes may show a stronger effect 
on surface temperature and salinity than in the north, 
The most striking feature in temperature and, particularly, 
in salinity distribution at greater depths is the outflow 
of Mediterranean water, Part of this very saline water 
spreads to the south along the West African continental 
slope at a depth of about 1250 m, On its way to the south 
it mixes with the adjacent water masses, But there are 
still distinct admixtures of Mediterranean water in the 
upwelling area south of 20°N (Meincke et al., 1975).