La Niña

Quick Facts

The phrase "La Niña" is spanish for "the girl" and sometimes called "El Viejo" (old man). It is characterized by unusually cold ocean temperatures in the equatorial Pacific. In comparison, El Niño is characterized by unusually warm ocean temperatures in the Equatorial Pacific.

La Niñas appear approximately every 4-5 years. They typically last 1-2 years.

Global climate abnormalities of La Niña are less pronounced and in some areas tend to be the opposite of those associated with El Niño. However, the effects of La Niña are not always opposite to that of El Niño.

After an El Niño, the climate does not always swing to a La Niña phase. There have been only 17 moderate to strong La Niñas compared to 25 moderate to strong El Niños since the turn of the century.

La Niña is a natural phenomenon in the climate system and have been occurring for centuries. Detailed observations from ships led to systematic instrumental record keeping in the earlier half of this century.

It is believed that La Niña's cooling of the equatorial Pacific tend to favour hurricane formation in the western Atlantic. In contrast, El Niño conditions tend to suppress the development of tropical storms and hurricanes in the Atlantic, but increase the number of tropical storms over the eastern and central Pacific Ocean.

La Niña usually brings colder winters to the Canadian west and Alaska, and drier, warmer weather to the American southeast.

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