BY STAFF REPORTER
Agricultural commodities face substantial risk from climate change because of their sensitivity to and dependence on weather variables. One such commodity is coffee, a crop and beverage of importance in international trade. The two species of coffee with economic importance are the Robusta coffee (Coffea canephora Pierre) and Arabica coffee (Coffea arabica Linnaeus). Arabica coffee has relatively higher demand (over 70% of the world coffee market) due to its higher beverage quality.
Worldwide, there are five key agroecological zones suitable for producing Arabica coffee, classified on the basis of temperature and rainfall characteristics. These areas are between latitude 20° N and 25° S at altitudes ranging between 700 and 2000 m.a.s. Arabica coffee is more sensitive to climatic factors than robusta coffee and thus is expected to be affected more by climate change.
This is because Arabica coffee is grown in specific climatic and biophysical envelopes coupled with a narrow genetic diversity. As such, there is evidence that climate change is reducing area suitable for coffee, limiting yield, and increasing the risks of pests and disease.
These biophysical impacts eventually impinge on the livelihoods of 25 to 30 million smallholder coffee farmers who produce the majority of the world’s coffee.
In addition to the general requirements for Arabica coffee production, and perhaps most importantly, coffee quality profiles are strongly influenced by local climatic (rainfall, temperature, humidity and radiation), topological (elevation, slope angle and aspect), and edaphic (soil depth, acidity/alkalinity and fertility) factors.
These give the coffee distinctive characteristics specific to production areas. The combination of these factors is unique to each region and thus difficult to replicate, and slight modifications will affect the eventual profile of the coffee, but impact studies on this important aspect are missing. The effect is such that even when the same coffee variety is planted in different areas, the profiles will be different.
This terroir influence in coffee is so strong that it can be detected by chemical traces.
As such, grading and classification of coffee on the global market are based on the roast appearance and cup quality (flavour, flagrance, acidity and body), bean physiognomies (size, shape and colour), the density of beans and number of defects.
All of these characteristics are heavily influenced by the geographic characteristics (climate, altitude and soils) of the area of cultivation, the botanical variety and to some extent the preparation (washed or unwashed). In addition, the use of geographical indicators of origin as proxies of product and process quality have grown immensely in the single-origin coffee markets.
The demand for specialty coffee is increasing across world markets, especially as they are used also in blending with lower quality coffees to create instant coffees. This creates opportunities for coffee growing countries and smallholder communities to receive a premium price of about + 20 to + 50% compared to regular coffee beans.
Researchers from parts of Africa and Europe have shed new light on how climate change may affect what’s considered “specialty coffee” growth in Ethiopia throughout the rest of this century.
Incorporating advanced modeling for climates, topography and soils using specific geographical reference points throughout the Ethiopian coffee lands, the research provides a first-of-its-kind prediction of how specific Ethiopian coffee growing regions will be affected through 2090.
At the same time, the research explains the market-related consequences of such changes, identifying the real or perceived value of certain Ethiopian origins or geographic indications such as Yirgacheffe, Sidamo, Harar, Nekemte and Limu within the differentiated specialty coffee market.
A gross over-simplification of the research’s findings might say that suitable arabica coffee growing land areas are expected to change along with ongoing climate changes, with many existing areas becoming unsuitable, and many currently unsuitable areas becoming suitable. Importantly, the conditions required for high-quality “specialty” grade coffee are expected to worsen in nearly all of the regions, according to the study’s authors.
“The results show that we can expect an overall increase in coffee growing potential in Ethiopia but a decrease in most specialty coffees (except Nekemte) by climate change from the near-future to the 2090s,” they wrote.
Overall, the research presents a more focused view on coffee and climate as compared to the landmark 2014 climate study that predicted that the current suitable land for arabica growth worldwide could be cut in half by 2050. Subsequent studies that have provided map models, predicted new elevation requirements for coffee growth, and predicted the extinction of wild arabica species, particularly in Ethiopia, without intervention.
A major study in 2017 predicted that as much as 59% of Ethiopia’s current (then) coffeelands could become unsuitable for coffee growth by the end of the century due to climate change.
The new study – led by author Abel Chemura, a post-doctoral researcher at the Potsdam Institute for Climate Impact Research (PIK) in Germany – goes even further by addressing agriculural factors that Third Wave coffee subscribers might refer to as “terroir,” a phrase poached from the wine industry.
“In addition to the general requirements for Arabica coffee production, and perhaps most importantly, coffee quality profiles are strongly influenced by local climatic (rainfall, temperature, humidity and radiation), topological (elevation, slope angle and aspect), and edaphic (soil depth, acidity/alkalinity and fertility) factors,” the authors of the study, published this month in “Scientific Reports,” wrote. “These give the coffee distinctive characteristics specific to production areas. The combination of these factors is unique to each region and thus difficult to replicate, and slight modifications will affect the eventual profile of the coffee, but impact studies on this important aspect are missing.”
The Ethiopian Herald June 22/2021
