CRA: History and Distribution of Temperature Increases in the West African Cocoa Area
- Steven Haws
- Jun 3
- 3 min read
Updated: Jun 6

Crop surveyors and others in the cocoa areas of Côte d'Ivoire and Ghana have reported often during 2024-2025 that temperatures there have been unusually high. Although reports from the national meteorological offices often have failed to confirm that temperatures have been high compared with other recent years, the reports do show that temperatures have been consistently higher than those of past decades. The two charts below confirm rising temperatures in the cocoa area. Typical highs today are about 3°C higher than during the 1980s. The progression of colors from cool blues to warm yellows and oranges to red for 2025 coincides with the advance to each new decade. Data were collected from NOAA's Global Summary of the Day (GSOD).
Studies of cocoa yields and temperatures have reported that yields at first rise with temperature, then decline above about 32°C. The charts show that maximum temperatures above that threshold have become steadily more common with each decade. In the 1980s, temperatures exceeded 32°C only in the Harmattan period of Jan and in Feb-Mar. Forty years later, NOAA reports maximum temperatures below 32°C only during Jul-Aug. During the past three years, cocoa prices have risen four-fold due to poor African crops. Explanations for the poor crops have cited possible reasons: aging trees, industry and national campaigns against child labor and further deforestation, disease, and low farm prices. Temperatures now are joining the list of potential problems for cocoa cultivation in Africa.
The rise in temperatures seen in West Africa doubtless is part of the global rise in temperatures. The bubble chart below uses data from the national weather agencies of Côte d'Ivoire and Ghana to compare the rise in temperatures there with the global rise and to examine whether the rise has been uniform across the area. Data are available for most of the past 20 to 25 years for most national meteorological office stations of Côte d'Ivoire and Ghana. The data was sourced directly from the national agencies. Data are available for six stations in the cocoa area of Côte d'Ivoire and eight stations in the cocoa area of Ghana. Côte d'Ivoire reported the average maximum during each 8-11 day "dekad" i.e. nominal 10-day period. Ghana reported daily maximum temperatures.
Average high temperatures during about the past 20 years have increased in the cocoa areas of Côte d'Ivoire at about 0.65°C per 10 years. In Ghana, they have increased at about 0.5°C per 10 years. A website of U.S. NOAA states that Earth's temperature has risen 0.36°C per 10 years since 1982. The rate of increase in West Africa's cocoa area has been more than 50% faster.

The fastest increases are concentrated in the cocoa areas. Increases at the coast and northward into the areas toward the Sahel have been less. Deforestation probably is the reason for the rapid increase in the cocoa areas. Deforestation has reduced the tree cover available to reflect light or convert it into plant growth. As dense original forest was replaced by cocoa and other crops, the temperature of that area rose faster than earth's average rise.
The outlook for cocoa production in coming years very unclear. The relationships between temperature, rain, humidity, sunlight, soil moisture, and other factors that influence cocoa trees are complex and investigation has been minimal. For example, while temperatures have increased, so has humidity increased enough that crop surveyors mention these together. Because cocoa is a native plant of mid-growth fauna of the Amazon rain forest, high humidity may dampen the effect of high temperatures. The parallel increases in temperature and humidity are visible in the reports of Veriground stations. A major objective of CRA's Veriground weather monitoring project is to develop enough data that the relationships can be identified and applied to monitoring and improving cocoa and other crops of Africa and of other origins.
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