What is El Nino? How does it affect the climate?

Instead of binging on your outdoor bucket list – heading to the beach, snorkeling, diving, rock climbing, ziplining adventure, hiking, and an awesome road tripping, you chose to stay home. You are pretty sure that these outdoor activities will stay for a while in the bucket so you freshen yourself up and head to work. But long before you reached the office, you already have a frizzy hair, sweaty underarms, and a smudged makeup. These are some of the many hassles brought about by the scorching heat of El Nino.

El Nino is a weather phenomenon that occurs irregularly every two to seven years in the eastern tropical Pacific. When the trade winds that usually blow from east to west weaken, the sea temperature starts rising. A 0.5 degree Celsius (0.9 degrees Fahrenheit) increase in the surface temperature over the historical average for three consecutive months officially declares an El Nino. Due to the vastness of the Pacific basin, covering one-third of the planet, any seemingly small rise in temperature results in a chain of complex atmospheric impacts. It also changes the amount of rainfall and wind patterns. What triggers El Nino remains a scientific mystery.

The Peruvian fishermen first recognized the relationship of the unusually warm water and their anchovy catch. They further observed that the massive tailing of fish happens every three to seven years and between December and January. Spanish immigrants coined the phenomenon, El Nino, meaning “the little boy” because this often arrives around Christmas. Is this “little boy” good or bad?

Strong events can temporarily disrupt weather patterns around the world, typically making certain regions drier while others are wetter. The strongest, massive El Nino, appeared in 1997-98, with an estimated 2300 deaths around the world and S35 billion damages. Mongolia’s temperature reached a burning 108F, Peru experienced torrential flooding, California and Mississippi swept by flashed floods, Gulf Coast stricken by storms, Florida hit by tornadoes.

El Nino also transfers heat stored in the deeper layers of the ocean. Warm water in the ocean pushes the colder water downward, blocking the important upwelling of the nutrient-rich water from the bottom. When this happens, there won’t be enough nutrients available for the plankton to feed on. Fishes feed on the plankton; as the plankton is reduced, so are the fishes. Historic observations have shown that animals that normally feed on the sea life suffer, causing fisheries to suffer too.

El Nino’s widespread is much noticeable on the land. For instance, in the Western United States and Central and South America, the warm air and moisture released in the atmosphere lead to increased rainfall. Above-average rainfall can also cause diseases spread by mosquitoes, such as dengue, malaria, Zika virus, and chikungunya. These diseases can be spread even in areas where they don not usually occur. In Southeast Asia and Australia, opposites occur as these areas suffer from drought, wildfires, and colder ocean waters.

The weather forecaster and TV news have probably scared us a lot with the negative effects of the El Nino phenomenon. And little did we know that El Nino also has beneficial effects. Some benefits include: fewer hurricanes and other tropical cyclones in the North Atlantic, milder winters in southern Canada and the northern continental United States, water supplies in the southwestern is replenished, fewer instances of malaria in southeastern Africa due to drier weather.

A higher return in fisheries is enjoyed during warmer winter in Canada. The increase in oil prices means more significant oil revenues for Canada, being the world’s fifth-largest oil producer. The typically wet weather in California during El Nino is helpful in crops like lime, avocado, and almond. Plentiful rains helps to boost soybean production in Argentina, which exports 95% of the soybeans it produces. The fewer hurricanes on the east coast and more hurricanes on the west coast of Mexico during El Nino generally bring stability to the oil sector and boosts exports.

Although there are both winning and losing countries from an El Nino event, the adverse effects on losing countries outweigh the good effects on winning countries. On the one hand, a dry spell troubles those who face below-normal rain and drought. However, it is good news for those who can experience double the average rain. El Nino is either good or bad, depending on where you live.

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