Climate change presents a “systemic” threat to global coffee harvests, a new study has found.

While past such crises have only threatened individual regions, the new risks could cause regional or even global failures in coffee crop yields, according to the paper published in PLoS Climate on Wednesday. 

Rising danger: “Since 1980, global coffee production has become increasingly at risk of synchronized crop failures,” the researchers, from Australia’s leading state-sponsored scientific agency, said in a statement. 

They were referring to the possibility that overlapping climate disruptions could “affect multiple key coffee-producing areas simultaneously.” 

Widespread disruption: The researchers found that between 1980 and 2020, climate hazards had increased in number and severity across the 12 leading coffee-producing countries. 

• The nature of these crises had shifted too.
  
• In 1980, the biggest threat was overly cold weather.
• Now, it’s temperatures hot enough to kill plants. 

Making things worse: The hotter phase of the El Niño Southern Oscillation — which is expected to return this year — poses a particular threat to global coffee supplies, the researchers found.

What is El Niño? A broad atmospheric pattern that typically brings hot, dry conditions to Southeast Asia, as we reported. 

That pattern is repeated in northern Latin America — and reversed in the continent’s southern half, which can lead to torrential, crop-ruining rains, according to U.K.-based coffee news site Perfect Daily Grind. 

Complicating matters: In Brazil, coffee yields are often higher during El Niño years, a 2020 study in Theoretical and Applied Climatology found. 

El Niño’s hottest days hit the country when coffee crops are pushing up new branches — giving them an important boost at a critical time, the researchers wrote.

Global crisis: Today, failure in one country’s coffee harvest doesn’t lead to huge price spikes or shortages, because other countries can cover the deficit. 

In the future, that may not be true: failures may be “synchronized,” the researchers wrote.