southern oscillation

noun

1. a low-latitude fluctuation of atmospheric pressure closely linked with El Niño events, specifically the periods of El Niño warming and La Niña cooling.

southern oscillation

1. The cyclic variation of atmospheric pressure at sea level between the eastern and western regions of the southern Pacific Ocean as a result of the periodic cooling and warming of surface water known as La Niña and El Niño. It has an average period of 2.33 years.

Word History and Origins

Origin of southern oscillation¹

First recorded in 1920–25