RENEE MONTAGNE, host:
Coffee growers have an extra reason to fear climate change. Coffee plants are notoriously sensitive to weather. And those who recently attended the World Coffee Conference in Guatemala are trying to figure out how to prepare for the possibility of a warming planet. Murray Carpenter covered the conference and began his report at a coffee farm nearby.
MURRAY CARPENTER: On a sunny afternoon, Eduardo Falla is using a wooden rake to turn the coffee beans drying in the sun on San Sebastian Farm. The farm sits beneath two volcanoes in Guatemala's Antigua Valley. And Falla says its award-winning coffee flavor is a factor of the rich volcanic soils and the climate.
Mr. EDUARDO FALLA (San Sebastian Farm): (Spanish spoken)
CARPENTER: The microclimate we have is special, Falla says. The temperatures rise, more or less, to 79 degrees and fall to 50 degrees at night. This is part of what gives it the quality.
The world coffee market is not in imminent danger. But small changes in temperature and precipitation can have big impacts on coffee quality and quantity. So growers like Falla are starting to think of ways to adapt to a changing climate. One strategy is moving coffee production to cooler regions.
Mr. PETER BAKER (CABI Bioscience): You can move up the mountainside as it gets warmer, but you actually run out of space, because mountains have this unfortunate property of being pointed.
CARPENTER: Peter Baker studies coffee for the nonprofit CABI Bioscience. He says coffee plants are fussy, especially the fine Arabica coffees that Americans prefer, which are typically grown in tree-shaded farms in the mountains.
Mr. BAKER: I often call coffee a Goldilocks plant. It likes it not too hot, not too cold. It likes it not too wet, not too dry. And so the conditions are really quite limiting and farmers have a real struggle, as we've seen in Colombia this last year or so. They've had the heaviest rainfall in recorded history, really.
CARPENTER: Colombia's rains were associated with a strong La Nina weather pattern, which can not be blamed directly on climate change. But Baker says the record rainfalls, which decreased Colombia's coffee harvest by a quarter last year, are consistent with the generally more chaotic weather that climate models predict.
For its part, Colombia's national center of coffee research has developed more than 200 weather stations to better advise farmers and document climate trends. And Brazil, the world's largest coffee producer, is also planning ahead for a changing climate.
Mr. EDUARDO ASSAD (Brazilian Agricultural Research Corporation): The problem of coffee in Brazil is if we increase the temperature, you have the problems of the flowering. This is the first problem. The second problem is the water deficit.
CARPENTER: Eduardo Assad of the Brazilian Agricultural Research Corporation says warm temperatures can cause coffee to flower early, reducing productivity. He says Brazilian researchers are trying to develop coffee hybrids better adapted to warmer and dryer conditions. But that could take years. Alternately, the coffee farms might have to move.
Mr. ASSAD: We have two million hectares of coffee in Brazil, and with the new scenarios of climate change, maybe this production can go to the south of Brazil.
CARPENTER: Back under the volcanoes on San Sebastian Farm, Eduardo Falla is looking over some coffee plants that have flowered, but only on half of the branches.
Mr. FALLA: (Spanish spoken)
CARPENTER: He says the rain that fell two weeks earlier was insufficient. And if the anticipated rains don't arrive soon, he will irrigate in order to stimulate more flowering.
And it may cause connoisseurs to cringe over their coffee cups, but a warmer climate will encourage more coffee farmers to plant the hardier, caffeine-rich but bitter, robuster varieties over the mild, tasty Arabica coffees.
For NPR News, I'm Murray Carpenter.
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