By Colleen Luckett

(This is part one of a two-part blog.)

Climate change is affecting the planet, with overwhelming evidence showing human-generated activity is causing current climate shifts. And, unfortunately, the tropical latitudes—where the poorest countries are and where coffee is grown—will get the worst of it. Climate change is intensifying at a rate never before seen by farming communities, putting at risk the farming families’ livelihood, food security, and well-being.

Coffee production depends strongly on a regular sequence of weather events. Ideal climate conditions for Arabica coffee are

• A dry period of three months to stress trees in order for them to flower well, but not too long of a dry spell, or trees will become weak
• A good soaking to initiate flowering, but not continuous rain, as this will affect the fruit set
• Not too high a temperature, which can cause a range of physiological problems, including early flower death
• Regular rainfall throughout berry development
• A drier period coming up to harvest
• A dry period around harvest to support picking and sun drying (ideal but not the case for all coffee production countries)

The U.N.’s Intergovernmental Panel on Climate Change predicts an increase in global temperatures of 3.6 to 7.2 degrees Fahrenheit in the next 20 years, with even greater temperature increases in many tropical regions. The best temperature range of the Coffea arabica tree (source of 70% of the world's coffee) is 64°–70°F, which occurs most consistently in upland elevations of tropical countries. Arabica 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 may not sound bad, but it 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, and even spawning stem tumors.

As a result, according to a 2014 report by Coffee Barometer, areas suitable for coffee production will decrease substantially by 2020 in important coffee-producing countries as diverse as Brazil, Honduras, Uganda and Vietnam. Meantime, global demand for coffee will continue to rise.

According to Fairtrade International, without changes to coffee varieties and farming practices, we can expect more vulnerability to pests and disease, unpredictable yields, and higher coffee prices.

An article at Time.com points out increasing damage over a longer time: “Study after study has laid out the threat climate change poses to the coffee industry. Rising temperatures will bring drought, increase the range of diseases and kill large swaths of the insects that pollinate coffee plants. About half of the land around the world used to produce high-quality coffee could be unproductive by 2050, according to a recent study in the journal Climatic Change. Another paper, in the journal Proceedings of the National Academy of Sciences, suggests that that number could be as high as 88% in Latin America.”

Water scarcity will be another result of climate change, according to an article in SCA (Specialty Coffee Association) News. In general, coffee thrives with 60 - 90 inches of annual rainfall. Below 30 inches is very stressful and likely to cause low yields of small beans, in addition to compromising the plants’ overall health. Significant decreases in rainfall therefore will especially harm regions whose annual rainfall is marginal for coffee production. For example, Nicaragua’s Ministry of National Resources and the Environment says rainfall will decline by an average of 30 percent within this century. To relieve their dependence on rainfall, farmers have introduced drip irrigation systems in some regions, but these add to the burden on declining water supplies.

Without action, these effects could have devastating human outcomes. Most coffee farmers are small landholders who live in systemic poverty and face chronic, seasonal food insecurity. Shifts in water availability could jeopardize their access to irrigation, as well as to fresh drinking water. 

You may have heard more dire warnings lately: these climate-change effects aren’t just predictions of the future. We are feeling the impact of climate change now. As Dr. Peter Baker and Dr. Jeremy Haggar noted at the SCAA (Specialty Coffee Association of America) event in 2007, coffee farmers in particular are eager to “develop strategies to confront it.”

In part two of this blog series, we’ll cover some of the coffee industry’s strategies for trying to stave off the more devastating effects of climate change on coffee farming. Meanwhile, if you have comments or information about coffee sustainability under climate change, please add them to the Comments section below.

Resources:

Shauna Alexander Mohr , “Coffee Quality and Sustainability: The Issues Challenging and Changing Our World.” SCA News, http://www.scanews.coffee/2011/11/04/coffee-quality-and-sustainability-the-issues-challenging-and-changing-our-world/

Michon Scott, “Climate and Coffee.” https://www.climate.gov/news-features/climate-and/climate-coffee. National Oceanic and Atmospheric Association.

Justin Worland, “Your Morning Cup of Coffee Is in Danger. Can the Industry Adapt in Time?” http://time.com/5318245/coffee-industry-climate-change/