Frozen Orange

This morning -- after the sun had been up for more than an hour -- I heard that it was 22 degrees below zero in the town of Orange, Massachusetts. Fahrenheit. Not wind-chill. This is cold, too cold to remind most normal people of the problem of global warming (more accurately known as climate change).

That was exactly my first thought, however, because I had already been intending to blog about an article on global warming and coffee by Orange's own Dean Cycon of Dean's Beans coffee. The article, Will Coffee Be a Casualty of Climate Change, focuses on the changes that highland coffee farmers in Colombia have already noticed. (I have to admit that my second thought was about the possibility of pipes freezing at the coffee company, possibly delaying my latest order of Ethiopian coffee!)

Almost all of the world's coffee grows in a "coffee belt" between the Tropic of Cancer and the Tropic of Capricorn, where temperature, day length, and sun angle remain relatively constant throughout the year. Not every place within that belt is suitable for coffee, though, because lowland areas are too hot and highlands too cold. For the finest coffees, the "Mama Bear" happy medium is generally found between 4,000 and 6,000 feet or so, toward the upper end of the altitudinal zone known in Latin America as Tierra Templada. In Nicaragua, for example, the frequent presence of clouds at this elevation results in cloud forests that create ideal conditions for shade-grown coffee.

In certain very tall mountains, warming temperatures tend to shift the zones upward, and if this happens gradually enough, perhaps coffee can be cultivated in new areas. The changes may be too rapid for this to take place, of course, and an important hypsometric reality is that less land is available at higher elevations. In fact, many of the mountains of Central American coffeelands are not much taller than 6,000 feet, so that any upward movement of the coffee zone would be literally into thin air.

Diagram by Mark Healy, Harper College