La niña

From Glossary of Meteorology

La Niña

The most common of several names given to a significant decrease in sea surface temperature ("cold events") in the central and eastern equatorial Pacific.

La Niña is the counterpart to the El Niño "warm event," and its spatial and temporal evolution in the equatorial Pacific is, to a considerable extent, the mirror image of El Niño, although La Niña events tend to be somewhat less regular in their behavior and duration.
See also ENSO.

Philander, S. George 1990. El Niño, La Niña, and the Southern Oscillation. Academic Press, International Geophysics Series, Vol. 46.