The highlands of
southwestern Ethiopia should be ideal for growing coffee. After
all, this is the region where coffee first originated hundreds of
years ago. But although coffee remains Ethiopia’s number one
export, the nation’s coffee farmers have been struggling.



The Arabica coffee grown in Ethiopia and Latin America is an
especially climate-sensitive crop. It requires just the right
amount of rain and an average annual temperature between 64 degrees
Fahrenheit and 70 degrees Fahrenheit to prosper. As temperatures
rise - Ethiopia’s average low temperature has increased by about
.66 degrees F every decade since 1951, according to the country’s
National Meteorological Agency - and rains become more variable,
Ethiopian coffee farmers have suffered increasingly poor
yields.

Last year was especially bad, with exports dropping by 33
percent. Some have moved their coffee trees to higher elevations,
while others have been forced to switch to livestock and more
heat-tolerant crops, such as enset, a starchy root vegetable
similar to the plantain.

Now, there is evidence that a warming climate may be linked to
one of the major threats facing the coffee industry in Ethiopia and
elsewhere: A tiny insect known as the coffee berry borer beetle has
been devastating coffee plants around the world, and new research
suggests even slight temperature increases promote the spread of
the pest.

The beetle is a relatively recent problem in Ethiopia and Latin
America, where most Arabica coffee is grown. A field survey of
Ethiopia’s coffee-growing regions conducted in the late 1960s found
no trace of the beetle, but in 2003 researchers reported that the
pest was widespread.

Drought and heavy rains during harvest time may be the
prevailing problems for coffee growers in Ethiopia and other
countries; but the lack of an effective treatment for the coffee
berry borer is cause for concern, especially given new research
findings tying the spread of the beetle to rising
temperatures.



Coffee may not be a basic food crop, such as wheat, but it is
arguably one of the most important agricultural products. Valued as
high as $90 billion a year, coffee, which is grown in more than 70
countries, is one of the most heavily traded commodities in terms
of monetary value. Seventy percent of the world’s coffee comes from
small, family-owned farms and more than 100 million people are
dependent on the crop for their livelihood.

Researchers estimate that the coffee berry borer href=”http://www.springerlink.com/content/h084lp6572887824/”
target=”_blank”>causes more than $500 million in damages each
year, making it the most costly pest affecting coffee today.
Coffee growers have tried various tactics to stop the beetle, but
to little avail. Pesticides don’t help, and even if they did, they
are an unfavorable option, given their negative effects on coffee
quality.

href=”http://e360.yale.edu/feature/spurred_by_warming_climate_beetles_threaten_coffee_crops/2312/”
target=”_blank”>Read more

Erica Westly is a freelance science writer
based in Brooklyn, New York. Her work has appeared in numerous
publications, including Scientific American, Slate, and the New
York Times.