News that global warming might threaten the world’s coffee supplies circulated quickly through Facebook over the weekend, alarming me among other drinkers.
A cup of morning coffee could be much harder to find, and much more expensive, before the century is out thanks to climate change and the possible extinction of wild Arabica beans.
That’s the warning behind a new study by U.K. and Ethiopian researchers who say the beans that go into 70 per cent of the world’s coffee could be wiped out by 2080.
Researchers at the Royal Botanic Gardens in Kew and the Environment and Coffee Forest Forum in Addis Ababa, Ethiopia looked at how climate change might make some land unsuitable for Arabica plants, which are highly vulnerable to temperature change and other dangers including pests and disease.
They came up with a best-case scenario that predicts a 38 per cent reduction in land capable of yielding Arabica by 2080. The worst-case scenario puts the loss at between 90 per cent and 100 per cent.
There is a “high risk of extinction” says the study, which was published this week in the academic journal Plos One.
That would be bad news for both coffee drinkers and coffee-producing countries such as Ethiopia, Brazil and Colombia, which in 2009/2010 shipped some 93 million bags of coffee around the world, worth an estimated $15.4 billion.
Most coffee is made from Arabica beans. They are prized for their genetic diversity and grow best at between 18 C and 21 C. Above that, the plants ripen too quickly — which affects taste — or grow too slowly. Other coffee stems from Robusta beans.
The study goes on to note that its results are “conservative” because it did not take into account the large-scale deforestation of the Arabica-suitable highland forests of Ethiopia and South Sudan.
The paper in question, “The Impact of Climate Change on Indigenous Arabica Coffee (Coffea arabica): Predicting Future Trends and Identifying Priorities” by Davis, Goel, Baena, and Moat, makes more conservative claims, noting that this is the first study performed. The abstract is below.
Precise modelling of the influence of climate change on Arabica coffee is limited; there are no data available for indigenous populations of this species. In this study we model the present and future predicted distribution of indigenous Arabica, and identify priorities in order to facilitate appropriate decision making for conservation, monitoring and future research. Using distribution data we perform bioclimatic modelling and examine future distribution with the HadCM3 climate model for three emission scenarios (A1B, A2A, B2A) over three time intervals (2020, 2050, 2080). The models show a profoundly negative influence on indigenous Arabica. In a locality analysis the most favourable outcome is a c. 65% reduction in the number of pre-existing bioclimatically suitable localities, and at worst an almost 100% reduction, by 2080. In an area analysis the most favourable outcome is a 38% reduction in suitable bioclimatic space, and the least favourable a c. 90% reduction, by 2080. Based on known occurrences and ecological tolerances of Arabica, bioclimatic unsuitability would place populations in peril, leading to severe stress and a high risk of extinction. This study establishes a fundamental baseline for assessing the consequences of climate change on wild populations of Arabica coffee. Specifically, it: (1) identifies and categorizes localities and areas that are predicted to be under threat from climate change now and in the short- to medium-term (2020–2050), representing assessment priorities for ex situ conservation; (2) identifies ‘core localities’ that could have the potential to withstand climate change until at least 2080, and therefore serve as long-term in situ storehouses for coffee genetic resources; (3) provides the location and characterization of target locations (populations) for on-the-ground monitoring of climate change influence. Arabica coffee is confimed as a climate sensitivite species, supporting data and inference that existing plantations will be neagtively impacted by climate change.