/ 1 June 2017

One and a half degrees to crisis

Burning up: African states are most vulnerable to rapid global warming caused by the Pacific oscillation.
Burning up: African states are most vulnerable to rapid global warming caused by the Pacific oscillation.

For Africa’s states to survive global warming relatively unscathed, temperatures cannot exceed a rise of more than 1.5°C. If they do, ecosystems will start to unravel and make life very complicated.

But African states have a problem: the world, through the United Nation’s Intergovernmental Panel on Climate Change, has agreed to do what it can to keep warming below 2°C.

That goal is enshrined in the Paris Agreement of 2015, which was signed by nearly 200 countries.

Even that looks like an optimistic target. Political crisis in the West means work to reduce carbon emissions has taken a back seat. In the United States, President Donald Trump is considering leaving the Paris Agreement.

And now, new research shows that African states have even less time than scientists previously thought to prepare for a warmer world. The research article, titled Trajectories towards the 1.5°C Paris Target: Modulation by the Interdecadal Pacific Oscillation, from the University of Melbourne in Australia, looked at this lesser-known weather system in the Pacific Ocean.

The Pacific oscillation happens in the same areas as El Niño, the phenomenon that rapidly warms the Pacific and drives droughts and floods across the world. But El Niño only lasts one to two years. The Pacific oscillation lasts a decade or more, either warming or cooling the planet.

Since 2000, it has helped to cool the planet. This has come at a time of rapid global warming, mostly as a result of people pumping out carbon emissions and trapping heat in the atmosphere.

The past three years have each consecutively taken the record for the hottest ever.

Last year’s El Niño helped to exacerbate this, creating conditions such as crop failure in Southern Africa. Half of South Africa’s critical maize crop failed.

Little attention has been given to the Pacific oscillation. Now, because of the growing concern of what a 1.5°C warming will do to Africa, an increasing body of research is being done to discover what happens if the world overshoots that mark.

Some of the research has already worked out that the Pacific oscillation is moving towards a warming phase. Most predictions were that this would drive the world towards being 1.5°C hotter by the 2030s.

The Melbourne research brings this date forward by at least half a decade to 2026.

That’s a serious problem for African states, where citizens are already vulnerable to climate shocks when factors such as rainfall patterns suddenly change. These states are consistently ranked as among the most vulnerable in the world to climate change.

Last year’s El Niño exposed this vulnerability. In Southern Africa, less rainfall meant crop failures and tens of millions of people going hungry.

Countries had to declare disasters to get aid in the form of food. In East Africa, cholera cases increased by 50 000, because of the floods that occur when El Niño arrives.

Research has also linked these sudden changes in temperature and weather to an increase in violence across the continent.

Lake Chad is an acute example of this, where militias use the lake’s dwindling water supplies — it has shrunk by 90% in half a century — to exercise power in surrounding countries, such as Niger.

Floods and droughts — and social consequences — make adapting to climate change critical for people across the continent.

This ranges from bringing irrigation to villages so they can farm in times of drought to improving sewerage so cholera is less of a problem when it floods.

But this takes time. The Melbourne research has shaved six years or more off the time left to adapt.