So great a Universitie, I think there ne’er was any;In which you may a Scholar be, for spending of a Penny.
This 17th-century couplet praised the virtues of London’s coffee houses, where instead of alcohol, customers could partake of a stimulating drink, the latest news, perhaps even a lively debate. In an age when water often wasn’t safe to drink, coffee provided a sobering alternative to alcohol. Though some detractors called it a “bitter invention of Satan,” coffee caught on, and some historians even credit coffee houses with seeding the Scientific Revolution.
Legend ties the discovery of coffee to a centuries-old monastery in the Ethiopian highlands, and after its introduction on the Arabian Peninsula, coffee was actively cultivated and traded before gaining popularity in Europe.
Between coffee houses and home, coffee lovers now consume more than 2.25 billion cups a day. Coffee counts among the most valuable tropical export crops on Earth, cultivated across more than 27 million acres. Small-scale farmers produce about 70 percent of the world’s coffee, and as many as 120 million people depend directly or indirectly on coffee production for their economic survival.
But coffee could be headed for trouble. Released in 2014, the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) predicts possible reductions in the area suitable for coffee cultivation by the year 2050. This finding is supplemented by other studies showing that rising temperatures have already bolstered coffee-plant pests.
What happens in a warmer climate
Optimal coffee-growing conditions include cool to warm tropical climates, rich soils, and few pests or diseases. The world’s Coffee Belt spans the globe along the equator, with cultivation in North, Central, and South America; the Caribbean; Africa; the Middle East; and Asia. Brazil is now the world’s largest coffee-producing country.
If Earth’s climate continues to warm over the coming decades, obstacles to coffee cultivation will multiply. Consider Arabica coffee (Coffea arabica), the species grown for roughly 70 percent of worldwide coffee production. Arabica coffee’s optimal temperature range is 64°–70°F (18°C–21°C). It can tolerate mean annual temperatures up to roughly 73°F (24°C).
Above those moderate temperatures, fruit development and ripening accelerate. (If you didn’t know, coffee “beans” are actually the pit, or seed, of the plant’s fruit.) Faster ripening might not sound bad, but it actually degrades coffee bean quality. Continuous exposure to temperatures up to and just over 86°F (30°C) can severely damage coffee plants, stunting growth, yellowing leaves, even spawning stem tumors.
Because of the importance of coffee to the rural economies of so many tropical countries, the latest IPCC report explored the potential impacts of a warming climate on coffee production in the Americas and Africa. The scientists forecast varying impacts in different Brazilian states: in Parana, a 10 percent reduction in suitable growing area; in Minas Gerais and Sao Paulo (the main coffee-growing states), a drop in suitable cropland from 70–75 percent to 20–25 percent of total land area; in Goias, coffee production would no longer be possible. Newly suitable areas would emerge in Santa Catarina and Rio Grande do Sul, but these new areas would only partly offset losses elsewhere.
The IPCC scientists also identified projected losses of coffee-growing lands in Guatemala, Costa Rica, Nicaragua, El Salvador, Honduras, and Mexico. Changing temperature and rainfall could reduce the Central American coffee-growing area between 38 and 89 percent by the year 2050 and raise the minimum altitude for coffee production from approximately 2,000 feet to 3,300 feet above sea level.
Press link for more: climate.gov