The Mischief of El Niño Phenomenon: What is El Niño?

If there are fires, El Niño is to blame. If there are no fires, it was El Niño. If there are floods, it was also El Niño. And if there are no floods, it is El Niño's fault. Today El Niño is on everyone's lips and almost everything bad that happens is attributed to it. This time it is, no more and no less, El Niño or the El Niño Phenomenon.

El Niño is a natural cyclical phenomenon that occurs at irregular intervals that can range from 2 to 7 years. It occurs at Christmas time, hence the name El Niño (El Niño Jesus), and lasts approximately 1 to 2 years. El Niño (also known as ENSO, an acronym for El Niño Southern Oscillation) is characterized by an influx of warm waters off the coasts of Peru and Ecuador. It contributes significantly to climate changes around the world because the atmosphere and the oceans are closely related.

The atmosphere and the oceans: their relationship

During normal conditions, winds blowing in an east-west direction with great intensity along the equator cause winds blowing in a south-easterly direction along the coasts of Peru and Ecuador to push away the warm, nutrient-poor surface water. As this occurs, cooler, nutrient-rich water from deeper depths rises to the surface to replace the receding water, generating the phenomenon known as upwelling.

In turn, the rising cold water cools the air above the surface, making it too dense to rise sufficiently to allow cloud formation. Thus, during normal periods, cloud formation and rainfall are limited to the western end of the Pacific, near Indonesia.

On the contrary, during the El Niño phenomenon, the winds blowing along the Equator change direction from west to east. These winds carry warm surface water towards the coasts of Peru and Ecuador, which together with the warm waters already in the area form a large layer of warm water, causing the cold waters to sink to more than 100 meters (109 yards), thus preventing upwelling.

The moist air above this warm layer becomes buoyant enough to allow the formation of thick clouds that produce heavy rain along the equator, which move in an easterly direction. These clouds in turn distort the upper wind flow (5-10 miles above sea level) causing the rain area, usually located over Indonesia and the far western Pacific, to move eastward toward the Central Pacific, resulting in unseasonable weather conditions in many regions of the globe.

The mischief of El Niño

The oceanic and atmospheric disturbances of El Niño have notorious consequences on the distribution of marine species of economic importance. Generally, when the phenomenon occurs, several important species for fishermen are less abundant (e.g. anchoveta). But also, as the saying goes, every cloud has a silver lining, because although some species are scarce, it is also true that on some occasions the number of warm water marine species such as dorado, billfish, and shrimp increases.

Reports on the El Niño phenomenon have indicated that in South America heavy rains have turned the Atacama Desert, famous for its arid climate, into a beautiful field of flowers. While in other parts of the world, such as NE Brazil, SE Africa, East Pacific Pakistan, and NE India, severe droughts are expected. These will bring reduced crop production as well as increased fires in wild vegetation areas.

The western United States has seen an increase in rainfall during one season of the year as well as the intensification of heat in another, resulting in more grasses that in the hot season become highly combustible material to fuel the dreaded wildfires.

Globally, the warming of marine waters brings with it an imbalance in the pattern of fish migrations. This in turn causes a decrease in the food supply for some animal species that frequent the area. This happens, for example, on the coasts of the Gulf of California, where there is a decrease in the number of seals and sea lions that frequent the western coasts.

The rise in water temperature has serious consequences for coral reefs. Corals are located in areas where the temperature is at the right limit for their survival. If the water temperature rises too high, corals lose the algae they live with to obtain food, turning white and even dying if the phenomenon is very severe or prolonged for a long time. In 1982-1983, one of the most severe El Niño events occurred, and about 80% of the corals located in Panama, Costa Rica, Colombia, and the Galapagos Islands died due to the loss of algae. To date, a large number of these reefs have not recovered.

In conclusion, what is the El Niño phenomenon? It is a cyclical climatic phenomenon that causes havoc worldwide, the most affected being South America and the areas between Indonesia and Australia, causing the warming of South American waters.