El Nino has officially arrived and is expected to gradually strengthen into the winter, increasing the risk of extreme weather later this year, from tropical cyclones spinning towards vulnerable Pacific islands to heavy rainfall in South America to drought in Australia and some parts of Asia.

After three years of La Nina, which often cools global temperatures, the opposite, El Nino is now underway, according to the U.S. National Oceanic and Atmospheric Administration's (NOAA) Climate Prediction Center on Thursday.

El Nino refers to an unusual warming of the ocean surface waters in the eastern Pacific Ocean. It generally occurs about every two to seven years and typically lasts nine to 12 months, but can sometimes last for years. It has an impact on ocean temperatures, the speed and strength of ocean currents, the health of coastal fisheries, and local weather from Australia to South America and beyond. Trade winds and the atmosphere are also impacted by El Nino.

"Depending on its strength, El Nino can cause a range of impacts, such as increasing the risk of heavy rainfall and droughts in certain locations around the world," said Michelle L'Heureux, climate scientist at the Climate Prediction Center. "Climate change can exacerbate or mitigate certain impacts related to El Nino. For example, El Nino could lead to new records for temperatures, particularly in areas that already experience above-average temperatures during El Nino."

El Nino is normally associated with record-breaking global temperatures.

The last El Nino was in 2016, when the world experienced its hottest year on record, which was about 1.1 degrees Celsius higher than the pre-industrial period. Fueled by climate change and El Nino, the global average temperature in 2023 or 2024 could reach new highs.

(Cover image via CFP)

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