El Niño-La Niña cycles to get worse with global warming

A new study published on Friday in the Journal Science Advances has suggested that global warming is likely to become double in frequency in this century. As a result, El Niño-La Niña cycles will also become stronger and more common.

According to the National Oceanic and Atmospheric Administration (NOAA), El Niño and La Niña are complex weather patterns that emerge as a result of variations in ocean temperatures in the Pacific. Both of them are opposite phases of El Niño-Southern Oscillation (ENSO) cycle describing the fluctuation in temperature between the ocean and the atmosphere.

The cycles function like a seesaw. At times, El Niño is referred to as the warm phase of ENSO as it brings warm water, producing more moisture and thus more intense thunderstorms. Whereas, La Niña is called the cold phase because it brings cooler temperatures.

El Niño’s higher waters generally happens every two to seven years, and they may raise sea levels provoking flooding. El Niño can also have a significant impact on weather patterns, ocean conditions, and marine fisheries across the world for an extended period of time.

As compared to it, La Niña causes low sea levels, and in case it drops dramatically then it may dry out shallow marine environments. For example, in the South Pacific islands, large amounts of corals could be killed due to them.

Researchers said if climate change continues than these sea level extremes are going to become more dramatic, stronger and frequent. Meteorologists have in fact done a prediction that El Niño will hit the US west coast towards the end of this year, and would last longer than usual.

In a press release, Matthew Widlansky, a researcher at the University of Hawaii at Manoa, said, “The possibility of more frequent flooding in some areas and sea level drops in others would have severe consequences for the vulnerable coastlines of Pacific islands”.

These are not news for the scientific world, since other studies have suggested the same. “Our results are consistent with previous findings that showed the atmospheric effects of both El Niño and La Niña are likely to become stronger and more common in a future warmer climate,” added Wenju Cai, a researcher at CSIRO in Australia.