(Read more UN predictions about how global warming will affect the globe.)
And "there is no real doubt that global temperatures will rise between 1.4 and 5.8 degrees [C]," said Philip Gwage, Uganda's deputy commissioner of meteorology.
Certain conditions are required for coffee growth, including cool temperatures and enough water, he pointed out. The average temperature in Uganda's coffee-growing area now is about 77°F (25°C).
If the temperature rises, only a few highland areas in Uganda could continue to grow coffee, Gwage added.
Although Uganda may also receive more rainfall from surface evaporation off east Africa's lakes, the increased precipitation could be erratic and not fall during the growing season.
Robusta, the main variety of coffee grown, would "essentially disappear," he said. Coffee-growing areas would be reduced to less than a tenth of their current size.
Neighboring coffee producers such as Kenya and Tanzania would also be affected, the Ugandan report predicts.
Fighting the Fire
To help prevent against the adverse effects of global warming, farmers are already adopting new growing strategies for coffee, a seasonal crop that thrives during Uganda's rainy, cool period between December and February.
The primary concern, farmers say, is ensuring the premium quality of Uganda's coffee—especially the reputation of the country's organic brands.
Farmers are growing trees densely to create cool shade for the coffee. They are also mulching—or covering soil with grass to hold onto water—and digging long terraces in the ground to retain rainfall.
But these efforts are not without obstacles.
George Kiryowa, a coffee farmer for 20 years, has been trying to implement the practices on his farm. But "the people have destroyed all the trees for timber," he said.
And because he can't afford extra labor, "these days we just use our hands, and the process is slow."
Kiroywa added that he now grows other crops such as cocoa—the plant source of chocolate—as a safety measure in case the changing environment does harm the coffee.
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