This is why the price of chocolate is going up

Increasing aridity is putting the production of cocoa beans in jeopardy. Narcisa Pricope is the Professor of Geography and Land Systems Science and Associate Vice President for Research, Mississippi State University. Valentine's Day and chocolate go hand-in-hand. But the future of this sweet treat is at threat, with prices likely to rise in response. The cacao tree, source of the cocoa beans used to make chocolate, thrives in humid conditions.

However, these conditions are under threat in key cocoa-producing regions like northeastern Brazil, where increasing aridity is jeopardizing the crop and the livelihoods of those who cultivate it. This worrying trend isn't limited to Brazil. Across West Africa, responsible for 70 per cent of global cacao production, and in other cocoa-growing areas like the Americas and Southeast Asia, shifting moisture levels are disrupting the delicate balance required for successful cacao cultivation.

These regions, vital to global food security and biodiversity, are facing the slow but relentless advance of aridity. This in turn will mean that price increases are likely to be passed on to the consumer. It comes as shoppers spoke out in fury when chocolate bar Freddo - fondly remembered by Brits for selling for just 10p - was spotted in a shop on sale for £1. That marks a ten-fold increase to when it was introduced onto shelves 20 years ago.

With aridity, a recent UN report paints a stark picture. Over the past 30 years, over three-quarters of the Earth's landmass has become drier. Drylands, now covering 41 per cent of the planet's land area, have expanded by an alarming 1.7 million square miles (4.3 million square kilometers) during that period – an area roughly half the size of Australia. This creeping dryness is not just a climate phenomenon. It’s a long-term transformation that may be irreversible and that carries devastating consequences for ecosystems, agriculture and livelihoods worldwide.

Aridity, while often thought of as purely a climate phenomenon, is the result of a complex interplay among human-driven factors. These include greenhouse gas emissions, land use practices and the degradation of critical natural resources, such as soil and biodiversity. These interconnected forces have been accelerating the transformation of once-productive landscapes into increasingly arid regions, with consequences that ripple across ecosystems and economies.

Human-induced climate change is the primary driver of rising aridity. Greenhouse gas emissions, particularly from fossil fuel combustion and deforestation, increase global temperatures. Rising temperatures, in turn, cause moisture to evaporate at a faster rate. This heightened evaporation reduces soil and plant moisture, exacerbating water scarcity – even in regions with moderate rainfall. Aridity began accelerating globally in the 1950s, and the world has seen a pronounced shift over the past three decades.

This process is particularly stark in regions already prone to dryness, such as Africa’s Sahel region and the Mediterranean. In these areas, reduced precipitation – combined with increased evaporation – creates a feedback loop: Drier soils absorb less heat, leaving the atmosphere warmer and intensifying arid conditions. Aridity is also affected by how people use and manage land. Unsustainable agricultural practices, overgrazing and deforestation strip soils of their protective vegetation cover, leaving them vulnerable to erosion. Industrial farming techniques often prioritize short-term yields over long-term sustainability, depleting nutrients and organic matter essential for healthy soils.

For example, in cocoa-producing regions like northeastern Brazil, deforestation to make room for agriculture disrupts local water cycles and exposes soils to degradation. Without vegetation to anchor it, topsoil – critical for plant growth – washes away during rainfall or is blown away by winds, taking with it vital nutrients. These changes create a vicious cycle: Degraded soils also hold less water and lead to more runoff, reducing the land’s ability to recover.

Soil, often overlooked in discussions of climate resilience, plays a critical role in mitigating aridity. Healthy soils act as reservoirs, storing water and nutrients that plants depend on. They also support biodiversity below and above ground. A single teaspoon of soil contains billions of microorganisms that help cycle nutrients and maintain ecological balance. However, as soils degrade under aridity and mismanagement, this biodiversity diminishes. Microbial communities, essential for nutrient cycling and plant health, decline. When soils become compacted and lose organic matter, the land’s ability to retain water diminishes, making it even more susceptible to drying out.