The phenomena El Niño and La Niña in Ecuador

Update of 08/June/2023 on El Niño phenomenon:

While the weather bulletins of April 13, 2023 did not detect the presence of El Niño phenomenon in the tropical seas, this Thursday, June 08, 2023, the forecasts have changed. The US weather agency NOAA has declared that El Niño phenomenon has begun. According to the agency, the phenomenon will gradually increase in intensity.

Its arrival in Ecuador is forecast from November or December 2023, according to experts at the Polytechnical National School of the Coast of Guayaquil. Heavy rains are therefore expected in the country at the end of the year, but the intensity and consequences of the phenomenon remain difficult for scientists to predict.

To find out more about the El Niño and La Niña phenomenon, the article is just below ↓

The last time of El Niño in Ecuador took place in 1998 according to the Oceanographic Institute of the Navy of Guayaquil (INOCAR). Now, scientists predict the reappearance of the phenomenon starting from the second semester of 2023.

What are these phenomena, and what are the consequences on the Pacific countries ?

El Niño and La Niña, two opposed weather phenomena

At the beginning, Peruvians fishers named El Niño the warm flow which was felt on the coasts of Peru and Ecuador at the time of Christmas. (“El Niño” means Jesus the child in Spanish).

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Nowadays, the word names the oceanic phenomenon which appear because of the anomaly of significant surface water temperatures in the equatorial Pacific Ocean.

El Niño is the large-scale warming of the ocean surface temperatures, while La Niña is the cooling of the same. These both opposed episodes are the phases of the El Niño-Southern Oscillation (ENSO). It is linked to a cycle of atmospheric pressure variations between the western and eastern Pacific Ocean, with an ocean flow cycle along the equator.

The usual meteorological situation and the unusual one

Out of the event of El Niño, steady east-west winds are well established on the north side of the Eastern Island high. Its trade winds dive the warm surface waters westward in the Pacific, and this movement of warm waters causes the cold waters to upwell in the eastern Pacific. During this usual situation, the precipitation remains west of the tropical equatorial Pacific.

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When the weather situation is particularly marked, it is called La Niña.

When it is El Niño, the pressures of the southern Pacific drop and also the trade winds. The warm surface waters, but also clouds and precipitations, move around the east and the Peruvian and Ecuadorian coasts.

These weather conditions appear irregularly, every 2 to 7 years, and can last from 8 and 12 months. The two last episodes of El Niño were in 1982 and 1998. According to the Institute of Atmospheric Physics Chinese Academy of Sciences (IAP), the frequency of these extreme events of El Niño has increased during these last four years. The main reason is the worldwide climate change, in particular because of greenhouse warming and atmospheric temperature variability.

Destructive weather events

Nowadays, these oceanic phenomena affect the worldwide climate with drought, flooding and rising average temperatures.

In Ecuador, El Niño causes various climatic episodes. The coast and the Andes region are affected by intense rainfall, which causes flooding and landslides. In other regions, there is drought and an increase in air and water temperatures. The temperature increase affects the population’s health, and also fauna and flora. Fishing is also particularly impacted. Indeed, because of the warming water, cold flows disappear and phytoplankton also, which are microorganisms necessary for the development of marine life.

During the 1982 and 1998 events, El Niño affected all the country, in particular the coastal provinces. Dozens of people died. Hundreds of houses had been flooded and destroyed, and also road infrastructures. The persistent and incessant rains of El Niño had damaged the soil. The flooding consequences impacted prices because of the huge loss of harvests and a large economical and political instability had been established.

And in 2023, what could happen?

The last two years were marked by the presence of the so-called “prolonged” La Niña phenomenon, i.e. the sea surface temperature is below average for 2 years.

Since January, meteorologists have logged an unusual increase of the ocean temperature, more than 1.5 degrees. It is therefore likely that the phenomenon repeats, 25 years after the last El Niño. This is what Inocar predicts. According to them, if the warming of the ocean doesn’t decrease, it will bring an atmospheric perturbation in the southern Pacific and the rainy season will be extended in the Pacific coast of the country. The event may therefore help the appearance of El Niño phenomenon in Ecuador from the half of 2023. Regarding its intensity, in the last two episodes, the sea temperature had reached 3 degrees above normal.

Unfortunately, the warm waters predict strong disturbances in Ecuador. Therefore, it is likely that the country will have to face heavy rainfall and numerous floods on the Pacific coast from July.