STiR coffee and tea magazine

24 STiR coffee and tea | 2022 Issue 5 (October/November) Suitability change for coffee by 2050 according to RCP 4.5 (intermediate emissions). A Central and South America, B West and Central Africa, C South and Southeast Asia. (RCP: Representative concentration pathway, a measure of the trajectory of greenhouse gas concentrations.) Courtesy of Public Library of Science https://doi.org/10.1371/journal.pone.0261976.g001 Current suitability and expected changes by 2050 for coffee in Vietnam. A current landscape and soil suitability, B current climate suitability, C current overall suitability, D suitability change under RCP 2.6 (low emissions), E suitability change under RCP 4.5 (intermediate emissions), F suitability change under RCP 8.5 (high emissions). (RCP: Representative concentration pathway, a measure of the trajectory of greenhouse gas concentrations.) Courtesy of Public Library of Science https://doi.org/10.1371/journal.pone.0261976.g001 While some young people study agronomy, marketing, and related skills to revitalize the family farm, many third- and fourth- generation growers abandon coffee planta- tions for other crops or for work in the cities. In Colombia, where 96% of coffee farms cover less than 1.4 hectares (3.5 acres), there were 600,000 family-owned farms in 2008. By 2018, the number had declined to 570,000. The count now stands at 540,000. The sunny side of climate change There is, however, hope. The same cli- mate projections that show the bottom tier of high-altitude coffee regions be- coming inhospitable also show new re- gions opening up to coffee cultivation. Countries and regions at the north- ern tips of today's growing areas in the Northern Hemisphere will become more suitable, including China and the United States. The same is true at the southern tips of areas in the Southern Hemisphere: Argentina, Uruguay, South Africa, New Zealand. Ethiopia, the native home of the cof- fee plant and the fifth biggest producer of arabica, should see its ability to grow coffee remain unchanged. Honduras, whose crop suffered se- verely recently, has significant land area at elevations more than 900 meters above the necessary minimum altitude for cof- fee. So Honduras' future looks good as it will continue to have high-altitude conditions after other countries' highest elevations become too warm for coffee cultivation. That could happen in ultra-high el- evation Nicaragua as well, where analysts say the optimum altitude for coffee will rise from 1,200 meters above sea level to 1,600 meters by mid-century. But it will take a while for these new areas to produce coffee. Moving farms to places where coffee is already being grown, though not with optimum output or quality, could prove a better bet than zones where cultivation has never been tried. Production in these low-output zones could be improved with new tech- niques, new varieties, and a new manage- ment approach. Enlisting wild species One long-shot effort that has paid off was a quest by coffee botanists to uncov- er and revive wild species that are resis- tant to rust and borer, yet with flavor ap- proaching the quality of Coffea arabica. Finding a new coffee that tastes great and also tolerates heat and drought is "the holy grail" of coffee research, according to Aaron P. Davis, a well-known scientist who for years has been on this quest at London's Royal Botanic Gardens, Kew. The re-discovery in 2018 of the West African Stenophylla species, presumed extinct for 100 years, was like stumbling

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