Given the money on offer, others will almost certainly move to fill our empty cups – and that could come at a huge cost to the environment. Magrach recently mapped out the areas suitable for Arabica farming and compared it to areas of natural interest. In the worst case scenario, she found that we will need to encroach on 2.2 million hectares of rainforest to meet the predicted demand – an area about the size of Wales. The result would be a significant loss of biodiversity.
There may be better solutions. Given its hardiness, Robusta will be better able to weather the changes; Magrach’s models even suggest that its preferred habitat may grow as a result of the rising temperatures. If so, a simple change in taste may offset the coffee crash – provided we can grow to love its bitterness. “It would definitely be better for the forests,” says Magrach. At the very least, she hopes that food labelling will make it clear in future whether the beans were farmed from vulnerable areas, so that consumers are aware of the environmental cost and can shop more ethically.
Others hope that improved farming techniques will instead keep the coffee flowing. Along these lines, the Coffee and Climate initiative is helping more than a dozen different coffee producers to join forces and share notes on the best ways to deal with the oncoming challenges. One option, for instance, is to graft Arabica strains to the roots of Robusta plants, making a hybrid that is more resistant to drought while retaining the preferred aromatic flavour. Alternatively, selective breeding could help produce a variety that combines the best of both Robusta and Arabica. “It’s something people are working on, but we’re not sure when the new strains will be available,” adds Magrach.
The livelihoods of farmers and others in the coffee business – at least 25 million people according to one estimate – depend on us finding an answer, fast. For the time being, the farmers face daily uncertainty, as Elisa Frank found during her interviews in Mexico. It can be hard to weather. Although many of the farmers listen to the TV forecasts, and try to prepare for the oncoming downpours, they can’t help but feel helpless, swept away by forces beyond their control.
Some of the farmers feel that the subject has almost become a taboo. “We talk very little about climate,” one told Frank. “We already know how it is here – and there is nothing we can do.”
David Robson is BBC Future’s feature writer. He is @d_a_robson on twitter.
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