Why do the major ocean currents in the north indian ocean reverse direction between summer and winter?

During the northwest monsoon (February and March), the wind blows from the continent and aids in the development of the North equatorial current. The current flows from east to west; and upon reaching the east coast of Africa, a good portion turns southward, crosses the equator, and becomes the Mozambique current. A strong countrcurrent exists south of the North Equatorial Current at this same time of the year. In August and September, during the southwest monsoon, the north equatorial Cur-rent reverses and flows west to east as the MON-SOON CURRENT. At the same time, the countrrcurrent seems to disappear.