What is El Nino? What is La Nina?
Updated: May 18
They are both part of an important climate phenomena called the El Niño-Southern Oscillation (ENSO), that affects temperatures, rainfall, and even the frequency of hurricanes. Read along, we'll explain!
El Niño and La Niña are part of a delicate balance between the atmosphere and the ocean in the Pacific basin, where each event acts as a counterbalance to the other.
🔥👶 El Niño brings warmth and disruption to the oceanic equilibrium, with warmer-than-average sea surface temperatures in the equatorial Pacific Ocean.
❄️👶 La Niña restores the balance by bringing cooler-than-average sea surface temperatures to the same region.
⚖️ The Delicate Dance of the ENSO Cycle
The ENSO cycle is a recurring pattern of temperature changes in the equatorial Pacific Ocean. It consists of three phases: El Niño, La Niña, and neutral conditions. The cycle dances to an irregular rhythm, with each phase lasting anywhere from several months to a few years.
💃🕺 The Atmospheric Waltz: How El Niño and La Niña Occur
El Niño and La Niña result from a complex interplay between the atmosphere and the ocean. Under normal conditions, trade winds blow from east to west across the equatorial Pacific, pushing warm surface waters westward. This allows cooler, nutrient-rich water to rise to the surface in the eastern Pacific, a process known as upwelling.
During El Niño, the trade winds lose their strength or even reverse direction, allowing warm water to pool in the eastern Pacific. This suppresses the upwelling of cooler, nutrient-rich water and raises sea surface temperatures.
In contrast, during La Niña, trade winds strengthen, leading to an increase in upwelling and cooler-than-average sea surface temperatures in the eastern Pacific.
🌧️ The Ripple Effects: Impacts on Global Weather
El Niño and La Niña can have significant effects on global weather patterns, like ripples spreading across the ocean. Some of the most common impacts include:
🔥 El Niño: Warmer and wetter conditions in the southern United States, Central America, and the Caribbean; drought in Southeast Asia and northern Australia; increased risk of flooding in coastal South America, etc.
❄️ La Niña: Increased rainfall in Southeast Asia and northern Australia; drier-than-normal conditions in the southwestern United States, Central America, and the Caribbean; cooler-than-normal temperatures in the western Pacific and warmer-than-normal temperatures in the eastern Pacific, etc.
🔭 Predicting and Monitoring the Climate Tango
Scientists use various tools and data sources to monitor and predict the occurrence of El Niño and La Niña events. These include satellite observations of sea surface temperatures, measurements of subsurface ocean temperatures, and computer models that simulate the interactions between the atmosphere and the ocean.
Next time you see friends Googling "El Nino meaning" or hear them ask "What is El Nino?", send them our way! 😉