LAUSANNE — A few decades from now, that steaming cup of coffee you enjoy (and rely on) every morning won't taste the same. Climate change, a multitude of alarming forecasts tell us, is threatening the precious bean, prompting researchers and industrialists alike to work on ways to make the plant more adaptable. The trick is to do so without decreasing the quality. Their mission? To save the species while keeping things as flavorful as possible.

The Climate Institute of Australia predicts that the land area deemed suitable for coffee growing could be reduced by half by 2050, and that wild coffee may disappear by 2080. A study by the Royal Botanic Gardens, Kew, in England, shows that in Ethiopia — the world's fifth largest coffee producer and the origin of Arabica coffee — nearly 60% of the current coffee-growing area could become uncultivable by the end of the century. If wild coffee plants disappear, great genetic diversity will be lost, especially for the development of new varieties.

The coffee bush is a fragile plant. A few imbalances and the quality and quantity of the crop can be significantly affected. Arabica coffee, native to the Ethiopian highlands, grows best between 800 and 2,100 meters of altitude, at temperatures between 18 and 22 °C with a certain alternation of dry and wet periods. Robusta coffee — which, as the name suggests, is more resistant — grows in tropical areas up to 800 m of altitude. It's better than Arabica at supporting high temperatures but is more sensitive to drought.

Coffee production could be reduced by half by 2050 — Photo: Blake Richard Verdoorn

Rising temperatures and drought don't just affect the quality of coffee, researchers say. They also facilitate the spread of certain diseases to areas that were previously spared. In Costa Rica, coffee rust — a leaf blight caused by the fungus Hemileia vastatrix — has moved up to 1,400 meters above sea level. Brazil, the world's largest coffee producer and exporter, has been hit by drought and insects, and this year had to temporarily allow imports of Vietnamese Robusta.

With a warmer climate, the coffee will be forced to migrate to higher patches of land, though this could actually improve its taste. "The aroma and quality of Arabicas deteriorate in places that are too hot or too dry," says Aaron Davis, one of the authors of the study on Ethiopia. "Normally, high altitudes give better coffee, because the maturation season is longer and fresher. But when the temperatures are too low, they influence the taste in a negative way."

Unfortunately, the higher in altitude coffee bushes move, the less area will be available. An even bigger problem, at least as far as taste is concerned, is that areas responsible for certain speciality Arabicas — places that, because of a certain soil content, produce rare, high-end strains — will become untenable. Thus, Ethiopia could lose its Harrar coffee with aromas of blueberry, blackberry, and cardamom. On a wider scale, traditional varieties like Bourbon, Typica, and Caturra are threatened because of their sensitivity to coffee rust, says Peter Baker, an expert with an initiative Coffee & Climate.

Toying with new tastes

Coffee companies take the threat seriously and are investing in the creation of new varieties of Arabica that will be more resistant to climate changes and diseases. Several new strains have already emerged. "Initially, they were less appreciated in terms of taste, especially those resulting from crosses with Timor, a natural hybrid of Arabica and Robusta. But since then the quality has improved a lot," explains Professor André Charrier, a specialist in coffee growing.

Obata beans have been developed with flavour notes of caramel, hazelnut and dried fruits. Another new variety, IAPAR 59, has a unique taste some describe as "chocolate-artichoke."

The future, it seems, belongs to new-generation of hybrids that are created from two genetically distant Arabica varieties and are more vigorous than their parent plants. That means mixing more robust varieties, on the one hand, with wild, more subtly tasting coffee strains. The new hybrids are so promising that they can already compete with pure Arabica varieties in major international taste competitions

Some 50 new hybrids are currently being tested in the research hubs of the World Coffee Research (WCR) organization, which brings together major players from the coffee industry.

"We researched the climate conditions in all coffee plantations in the world and defined the five main climates for coffee growing," says Christophe Montagnon, scientific director of the WCR. "Then we studied the impact of climate change in each situation to pick the best varieties."

The WCR and other research institutes are also working on hybridizations of Arabica with other species of coffee — such as Robusta or Stenophylla, from Sierra Leone — that are more drought resistant. So far, though, the taste isn't satisfactory because Robusta, which has more caffeine, is generally of lower quality.

The sequencing of the genomes of Arabica in 2017 and Robusta in 2014 have opened even more research prospects by making it possible to select specific characteristics from each species. "This precise gene mapping will help identify, among other things, the key precursors of taste and aroma present in green coffee, which are at the origin of the quality of the coffee in your cup," says Pierre Broun, director of the Nestlé R&D Center in Tours, France.

High-performance varieties

All experts agree, however, on the fact that these new plants don't make sense if nothing is done to protect the environment in which coffee grows. Several major players in the sector, such as Illy, Nestlé, Starbucks and International Coffee Partners, which brings together European groups including Lavazza and Tchibo, are investing in sustainable development programs.

One of the most prominent solutions would be agroforestry, which is a return to the origins of coffee. "The best coffees grow in their natural environment, wet areas in the shade of forests," says Benoît Bertrand, a researcher at the French Agricultural Research Centre for International Development. "For productivity reasons, we started to cultivate them in full sunlight. This intensive method stresses the plant even more, which we try to compensate by bringing in more fertilizer."

The European project Breedcafs, which Bertrand oversees, is there to help break this vicious circle. "Our goal is to develop varieties that have the same performance as crops in full sunlight and are less energy-hungry. It's like with car engines: We're trying to make them more and more powerful and economical at the same time."

Still, all these efforts to save coffee could become obsolete if global warming continues, researchers say. "There are limits to everything," Bertrand warns. "The plants will not grow at 50 °C. Research can accompany climate change, but if humans continue to damage the planet, we won't be able to save coffee or any other species. Even the new high-performing varieties won't help us."