Coffee and Climate Change

Why coffee is vulnerable to climate change

Coffee depends on more than a suitable annual average temperature. The timing of rain, the severity of the dry season and conditions during flowering and bean development all matter. A year with apparently adequate rainfall can still be difficult if water arrives at the wrong time.

Arabica, Coffea arabica, generally favours cooler growing conditions than robusta, the coffee traded from Coffea canephora. However, neither species has one fixed temperature limit: varieties, soil, water availability and management influence how plants respond.

Heat also changes the plant’s water balance. Warmer air can increase the demand for water from leaves; when water becomes scarce, coffee closes its stomata, the tiny pores through which it exchanges gases. This conserves water but can restrict photosynthesis, the process that supplies energy for growth and fruit development.

Climate change is therefore not simply a question of plants becoming too hot. It changes the combination of stresses they face. For the wider environmental context, start with coffee and the environment.

What projections of suitable land loss actually mean

The widely repeated claim that coffee could lose half its suitable growing area needs qualification. These studies model relationships between climate and coffee’s distribution. They do not directly predict harvested tonnage, farmers’ decisions or the effectiveness of future adaptation.

Two influential papers published in 2015 are often grouped together, although their results are not interchangeable.

RCPs, or Representative Concentration Pathways, describe different greenhouse-gas concentration trajectories. SRES A2a belongs to an earlier scenario framework. Neither is a prediction that one particular future must happen.

A necessary correction: Bunn’s headline concerns both commercial species and aggregates changes in suitability scores. It should not be presented as a precise forecast that half of currently cultivated arabica hectares will disappear. Ovalle-Rivera’s paper supports the broader warning, but does not independently establish that identical headline.

Reduced suitability means a location’s projected climate becomes less favourable according to the model. It does not automatically mean production ceases there, and a newly suitable location is not automatically available farmland.

Why the estimates remain uncertain

Distribution models infer tomorrow’s possibilities from where coffee grows today. They cannot fully represent every future variety, irrigation decision or change in shade management.

Researchers reviewing coffee physiology have also argued that elevated carbon dioxide could partly offset some heat effects by supporting photosynthesis. Controlled experiments and field enrichment studies provide evidence for that mechanism, but not a guarantee of protection against drought, pests or damaging weather.

The disagreement concerns the size of the damage and how much adaptation can achieve, rather than whether growing conditions are changing. Treat a global suitability map as a guide to broad risk, not a planting prescription for an individual farm.

Rising temperatures, pests and extreme weather

Heat affects the crop and its enemies

Higher temperatures can accelerate fruit development, potentially compressing the period available for bean filling and affecting quality. Water shortages can make the consequences worse. Survival alone is therefore an inadequate measure of success: farmers need a harvest with acceptable yield and quality.

Coffee berry borer, Hypothenemus hampei, is a small beetle whose larvae damage the beans inside coffee cherries. Temperature influences its development and reproduction.

Jaramillo and colleagues’ 2011 study combined distribution modelling with evidence of expansion into higher-elevation coffee areas in East Africa. Warming can make previously cool locations more favourable to the insect and permit additional generations. This does not mean every high-altitude farm will become infested, but it weakens the assumption that elevation alone provides protection.

Too little water and too much water can both damage harvests

Prolonged drought restricts growth and can be particularly damaging during bean filling. Heatwaves add stress when plants are already short of water.

Excessive rain creates different problems. FAO’s assessment published in March 2025 linked reduced Vietnamese production to prolonged dry weather, while excessive rain damaged Indonesian coffee cherries. Hot, dry conditions also affected Brazilian production expectations.

These examples show why “a warmer climate” is an incomplete description of the risk. Farms must cope with rainfall disruption and extremes as well as rising averages.

However, evidence that weather damaged a harvest is not, by itself, proof that human-caused climate change caused that particular event. Event attribution requires a separate analysis comparing its likelihood or intensity with and without human influence.

How coffee farming can adapt

There is no universal climate-proof production system. Effective adaptation starts with the local constraint: heat, unreliable rain, water shortage, disease pressure or a combination.

Better varieties, including F1 hybrids

Breeding can combine useful traits such as disease resistance, yield potential and tolerance of environmental stress. An F1 hybrid is the first generation produced by crossing selected parents; it is a breeding category, not a promise of drought tolerance.

World Coffee Research lists Centroamericano as an F1 hybrid well adapted to agroforestry, meaning cultivation alongside trees. Starmaya is another F1 hybrid, distinguished by its suitability for professional seed production rather than relying on tissue-culture propagation.

These are examples of breeding options, not universal replacements for existing varieties. A variety described as rust-resistant or high-yielding should not automatically be described as heat-resistant. Local trials need to establish how it performs under the farm’s actual conditions.

Shade and water management

Shade trees can soften temperature extremes around coffee plants. In a field study on Mount Elgon, Uganda, shaded systems had lower maximum temperatures than open-grown coffee.

However, trees also use water. That study found lower soil moisture in shaded systems and identified potential competition during drier years. More shade is therefore not always better: tree species, rooting patterns, spacing and pruning matter.

Water storage, carefully targeted irrigation and management that improves water-use efficiency can complement shade. Research on Indian robusta agroforestry systems stresses that the most useful response depends on the scale and location of the risk. An approach suitable for a region may still need substantial adjustment on a particular farm.

Higher altitude, where relocation is feasible

Moving uphill can provide access to cooler conditions, but it is not a simple solution. Farmers need suitable soil, access to land and the practical means to establish production elsewhere.

Potentially suitable higher ground may also be forested or protected. Clearing it would turn an adaptation response into another environmental problem. Deforestation and coffee explains that separate issue in detail.

The practical priority is to assess how much adaptation is possible on existing agricultural land before treating expansion as the answer.

Wild coffee species: valuable resources, not instant replacements

A 2019 assessment led by Aaron Davis at the Royal Botanic Gardens, Kew found that at least 60% of the 124 wild coffee species assessed were threatened with extinction. This was an assessment of the species recognised and evaluated at that time, not a permanent total for the genus.

The threats included habitat loss, climate change, pests and disease. Conserving wild populations preserves genetic resources that may help breeders develop future crops.

Coffea stenophylla illustrates the potential. Rediscovered in the wild in Sierra Leone in 2018, it attracted renewed attention through research published in 2021, rather than being rediscovered that year.

Davis and colleagues combined sensory assessment with climate analysis and reported an arabica-like flavour profile from a species associated with substantially warmer growing conditions. That makes stenophylla a promising research resource, not proof of a ready replacement for commercial arabica. Flavour and climatic tolerance are only part of what a dependable crop needs.

What climate change means for coffee prices and UK buyers

Weather-related harvest losses can tighten supplies and put upward pressure on coffee prices. FAO’s July 2026 analysis identifies drought, frost and excessive rainfall as important triggers of market shocks.

The effect is not a simple upward line. Supply, demand, expectations and the structure of the supply chain influence how international movements reach farmers and consumers. A higher market price also does not automatically compensate a farmer whose harvest has failed.

For a UK workplace buyer, the useful response is to ask suppliers practical questions rather than demand an unsupported “climate-proof” claim:

1. Which producing regions and varieties supply the blend?
2. What happens if a familiar component becomes unavailable?
3. What evidence supports any claims about farmer adaptation or breeding support?
4. How will substitutions be communicated and checked for flavour and machine suitability?

These are suggested purchasing checks, not a certification scheme. Keep adaptation separate from emissions reduction: helping a farm withstand heat is not the same as reducing the emissions associated with coffee. The latter belongs in carbon footprint.

Coffee and climate change is ultimately a question of both plants and people. Promising breeding and farming responses need to work under local conditions, with farmers able to put them into practice.