Climate change has often been a contentious subject. Scientists and climate experts argue that our use of the environment is causing the climate to change in an unfavourable way, whereas many sceptics insist that regular extremes of heat and cold are a normal part of the earth’s cycle.
However there is a known fact that cannot be denied: since the start of the 20th century the average temperature of the planet has increased by 0.93 deg. C, corresponding to a rise in atmospheric carbon dioxide levels, and it is still rising. This small change is deceptive because it is an average taken across all continents. In some places the increase is much more.
In the “coffee belt”, that is the regions between the tropics of Cancer and Capricorn where the best conditions for growing coffee are found, the increase in average temperatures are between 1.5 degrees and 4.5 degrees in the warmest months and will continue to rise. This has a potentially disastrous effect on the coffee we drink every day.
How Temperature Affects Coffee Growth
To ensure good growth coffee plants need specific conditions of temperature, humidity and light levels, normally found at elevations of 600 metres to 2000 metres for Arabica, and lower for Robusta.
Rising temperatures bring drought and disease to the plants, and kill off many of the insects that pollinate the plants. Recent studies indicate that around half of the land around the world that is currently used for coffee cultivation will be unproductive by 2050 and at the current rate most of the land will be affected by the end of the century.
In some regions this has already happened. In one year alone, from 2012 to 2013, rising temperatures in Latin America caused a “coffee rust” crisis. Coffee rust is a devastating fungus that causes the leaves to wither and fall off the plants, which can die within a year. In Honduras, Guatemala and Costa Rica more than half of the cultivated area was destroyed, and 350,000 workers lost their jobs.
Increased sunlight in drought conditions also affects the flavour and aroma of the coffee beans. Shade management and irrigation become critical, requiring more investment and higher costs with the resulting increase in global coffee prices.
While many industries are arguing over climate change and their responsibilities, the coffee industry is being the most proactive in looking for a solution.
Arabica, the most popular bean, has a low tolerance to rising temperature and is more susceptible to rust whereas the Robusta bean, normally used in instant coffee, resists heat and is easier to grow. Researchers at the Federation of Coffee Growers in Colombia are trying to develop hybrid beans with the best qualities of the two types of bean, to achieve the same flavour but more resistant to high temperatures.
The coffee giant, Starbucks, bought a 600 acre plantation in Costa Rica in 2013 to experiment with new strains of coffee plants that would be more resistant to heat and drought whilst also meeting the quality standards. They are currently trialling 50 different seed varieties, testing them for their resilience to climate as well as for their taste.
As temperatures rise, higher altitudes become more suitable for coffee growth. In Ethiopia, which is the fifth largest supplier of Arabica in the world, this is being trialled. It is estimated that in the future 60% of land in the country currently used for coffee will become unusable, affecting the 15 million Ethiopians employed there.
Previously land at elevations above 2,200 metres was unsuitable due to lower temperatures, but now coffee growers in Ethiopia are looking at relocating their farms to those levels along with forestation and forest conservation.
A Future Without Coffee?
Despite the many sceptical voices, there is a clear trend. Experts predict that there will be higher global temperatures, and extreme climactic variances with longer periods of rain and harsher droughts. Unless action is taken today, the situation will become irreversible. Many countries and companies in the coffee industry are trying desperately to find a way out of the problem, but as the climate continues to change they may not be able to keep up with all the challenges.
Coffee rust is only one of many potential destructive diseases that will eventuate. Coffee production can continue to move to higher land elevations, but there will eventually be a limit to how far they can go. Sadly, the ultimate solution is not just the responsibility of the coffee industry but in the hands of world governments. As the saying goes, how is that working out?