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El Niño’s arrival could be bad news for southern Africa

By Gemma Gatticchi
Thursday, Jul 20, 2023 Climate Crisis

It’s not just your imagination – the weather has been acting up and there’s a term for it: the El Niño-Southern Oscillation (ENSO).

ENSO has three phases: El Niño, La Niña and neutral. 

  • El Niño is when the ocean surface temperatures are warmer than average in a part of the Pacific Ocean. This kind of ocean warming affects the weather around the world
  • La Niña occurs when the surface water temperatures in that part of the Pacific are cooler than average

How do we know El Niño is in play?

Two things are characteristic of the weather event

  • The ocean temperature in the Pacific Ocean is at least 0.5°C higher than normal for three months in a row
  • There are noticeable atmospheric changes, such as lower rainfall

This phenomenon repeats every two to seven years. The record temperatures and flooding in the northern hemisphere are attributable to El Niño. But it has implications for South Africa and its neighbours too.

Down South

Do you recall Cape Town’s dreaded ‘day zero’ water crisis in 2018? El Niño-driven droughts were partly to blame for the water restrictions.

Researchers from South Africa’s Council for Scientific and Industrial Research say there are tell-tale signs that an ‘unusually strong’ El Niño is developing.

This could lead to higher temperatures and lower rainfall this coming summer, which could affect farming, human health and food security. What may help take the edge off is that El Niño is arriving after four straight seasons of solid rainfall.

Watch: In the video below, the BBC’s environment correspondent explains the consequences of El Niño

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