A Two-Degree Threat

Goal: After this lesson you can explain why a warming climate is an unusually sharp danger for cacao, and what farmers do about it. Subject: Geography | Run time: about 6 minutes

Quick recall

Last time we covered the producers and varieties. Two quick questions. One: which two countries grow most of the world's cacao? Cote d'Ivoire and Ghana (International Cocoa Organization, 2023). Two: which variety is about 80 percent of production? The hardy Forastero (International Cocoa Organization, 2023).

Why this matters

Here is a number that should stop you. If average temperatures rise by 2 degrees Celsius, up to 89 percent of the land that is suitable for cacao today could become unsuitable (Läderach et al., 2013). Not a quarter. Not half. Nearly all of it, in the leading producing countries.

The idea

Why is cacao so exposed? Go back two lessons. Cacao is a forest understory tree that needs steady heat, heavy rain, deep shade, and the midges that live in real forest litter (Coe & Coe, 2013). Every one of those is fragile. A warming climate brings drought and shifts the rain. It pushes temperatures past what the plant can take, and unlike coffee, cacao cannot just climb a mountain to find cooler air, because it grows at low elevation in the first place (Läderach et al., 2013). There is a second trap, and it is human-made. To grow more cacao, farmers often clear forest. But clearing the forest removes the shade and the midges the plant depends on, and it speeds up the warming that threatens the crop (Coe & Coe, 2013). So the easy way to grow more cacao today makes it harder to grow cacao tomorrow. What is the way out? The same word from the first lesson, agroforestry, growing cacao under a managed forest canopy instead of clearing the land (Coe & Coe, 2013). Shade trees cool the soil, hold moisture, and keep the pollinators alive. It is slower and it yields less per acre, but it keeps the system that cacao needs in place.

Picture it

Picture two cacao farms side by side. One is cleared ground, full sun, neat rows, and it looks productive for a while. The other is a layered forest with cacao tucked in the shade below taller trees. Now run the thermostat up two degrees. The cleared farm bakes and the midges vanish. The forest farm holds its cool and its flies. The 89 percent number is mostly about the first kind of farm.

Remember this

The fact to carry out: cacao's dependence on a hot, wet, shaded forest makes it one of the crops most exposed to climate change, with up to 89 percent of suitable land at risk from a 2 degree rise, and agroforestry is the main defense (Läderach et al., 2013; Coe & Coe, 2013). The forest is not the backdrop to cacao. It is the life support.

Quick check

Quick check. Why can't cacao escape a warming climate by moving to higher, cooler ground the way coffee can? Because cacao already grows at low elevation and needs lowland forest conditions, so there is no cooler high ground to climb to (Läderach et al., 2013).

Key Takeaways

A 2 degree Celsius temperature rise could make up to 89 percent of today's suitable cacao land unsuitable (Läderach et al., 2013).
Cacao is exposed because it depends on steady heat, heavy rain, shade, and forest midges, all of which a warming climate disrupts (Coe & Coe, 2013).
Clearing forest to grow more cacao removes the shade and pollinators the plant needs and speeds warming (Coe & Coe, 2013).
Agroforestry, growing cacao under a managed canopy, is the main defense (Coe & Coe, 2013).

Sources

Coe, S. D., & Coe, M. D. (2013). The true history of chocolate (3rd ed.). Thames and Hudson.
International Cocoa Organization. (2023). Quarterly bulletin of cocoa statistics (Vol. XLIX, No. 1). https://www.icco.org
Läderach, P., Martinez-Valle, A., Schroth, G., & Castro, N. (2013). Predicting the future climatic suitability for cocoa farming of the world's leading producing countries. Climatic Change, 119(3-4), 841-854. https://doi.org/10.1007/s10584-013-0774-8