<P> The Coriolis effect circulates North Atlantic water in a clockwise direction, whereas South Atlantic water circulates counter-clockwise . The south tides in the Atlantic Ocean are semi-diurnal; that is, two high tides occur during each 24 lunar hours . In latitudes above 40 ° North some east - west oscillation, known as the North Atlantic oscillation, occurs . </P> <P> On average, the Atlantic is the saltiest major ocean; surface water salinity in the open ocean ranges from 33 to 37 parts per thousand (3.3--3.7%) by mass and varies with latitude and season . Evaporation, precipitation, river inflow and sea ice melting influence surface salinity values . Although the lowest salinity values are just north of the equator (because of heavy tropical rainfall), in general the lowest values are in the high latitudes and along coasts where large rivers enter . Maximum salinity values occur at about 25 ° north and south, in subtropical regions with low rainfall and high evaporation . </P> <P> The high surface salinity in the Atlantic, on which the Atlantic thermohaline circulation is dependent, is maintained by two processes: the Agulhas Leakage / Rings, which brings salty Indian Ocean waters into the South Atlantic, and the "Atmospheric Bridge", which evaporates subtropical Atlantic waters and exports it to the Pacific . </P> <Table> Temperature - salinity characteristics for Atlantic water masses <Tr> <Th> Water mass </Th> <Th> Temperature </Th> <Th> Salinity </Th> </Tr> <Tr> <Th_colspan="3"> Upper waters (0--500 m or 0--1,600 ft) </Th> </Tr> <Tr> <Td> Atlantic Subarctic Upper Water (ASUW) </Td> <Td> 0.0--4.0 ° C </Td> <Td> 34.0--35.0 </Td> </Tr> <Tr> <Td> Western North Atlantic Central Water (WNACW) </Td> <Td> 7.0--20 ° C </Td> <Td> 35.0--36.7 </Td> </Tr> <Tr> <Td> Eastern North Atlantic Central Water (ENACW) </Td> <Td> 8.0--18.0 ° C </Td> <Td> 35.2--36.7 </Td> </Tr> <Tr> <Td> South Atlantic Central Water (SACW) </Td> <Td> 5.0--18.0 ° C </Td> <Td> 34.3--35.8 </Td> </Tr> <Tr> <Th_colspan="3"> Intermediate waters (500--1,500 m or 1,600--4,900 ft) </Th> </Tr> <Tr> <Td> Western Atlantic Subarctic Intermediate Water (WASIW) </Td> <Td> 3.0--9.0 ° C </Td> <Td> 34.0--35.1 </Td> </Tr> <Tr> <Td> Eastern Atlantic Subarctic Intermediate Water (EASIW) </Td> <Td> 3.0--9.0 ° C </Td> <Td> 34.4--35.3 </Td> </Tr> <Tr> <Td> Mediterranean Water (MW) </Td> <Td> 2.6--11.0 ° C </Td> <Td> 35.0--36.2 </Td> </Tr> <Tr> <Td> Arctic Intermediate Water (AIW) </Td> <Td> − 1.5--3.0 ° C </Td> <Td> 34.7--34.9 </Td> </Tr> <Tr> <Th_colspan="3"> Deep and abyssal waters (1,500 m--bottom or 4,900 ft--bottom) </Th> </Tr> <Tr> <Td> North Atlantic Deep Water (NADW) </Td> <Td> 1.5--4.0 ° C </Td> <Td> 34.8--35.0 </Td> </Tr> <Tr> <Td> Antarctic Bottom Water (AABW) </Td> <Td> − 0.9--1.7 ° C </Td> <Td> 34.64--34.72 </Td> </Tr> <Tr> <Td> Arctic Bottom Water (ABW) </Td> <Td> − 1.8 to − 0.5 ° C </Td> <Td> 34.85--34.94 </Td> </Tr> </Table>

The northern area of africa from the atlantic to the indian oceans