1.1.1 The hydrographical conditions in the Strait
of Bonifacio are strongly influenced by the region's landscape and
climate. In particular, there are frequent very strong currents (3-4
knots) largely determined by the winds. These strong currents have
already, on two occasions, caused the South Lavezzi signalling buoy
to shift. They derive from cyclonic and anti-cyclonic conditions and
are responsible for surface changes among the Tyrrhenian and Algero-Provencal
water masses. Movements originating in the Atlantic and Tyrrhenian
systems, being less subject to the vagaries of the weather where water
masses of permanent density are concerned, also affect the bathymetric
layer between 50 and 100 m. This situation explains (Romano, 2004),
at least for surface waters, the existence of strong currents, especially
as the strait between Corsica and Sardinia is characterized by a rise
in depths.
1.1.2 The tides are semidiurnal with diurnal inequality,
with a tidal range of less than 0.5 m.