Heavy rainfall during the cacao flowering season is a major driver of Ghana’s recent harvest fluctuations, new research finds. A study published in September by researchers at the Harvard University Center for the Environment in the U.S. found that heavy rainfall during cacao’s flowering and early pod development is linked to significant yield decreases. The researchers described how short, untypical rains during the flowering season, together with dry-season drought, is a major reason for recent fluctuations in Ghana’s cacao production. Ghana and Côte d’Ivoire together account for about 60% of global cocoa production, making West Africa central to the world’s chocolate supply. Cacao seeds are the primary ingredient in chocolate. The authors raised concerns about how these changing rainfall patterns could affect Ghana’s cacao industry, which is one of the West African country’s most important agricultural sectors. “Along with dry-season drought, [heavy rainfall during flowering and early pod development], those two factors alone explain about two-thirds of the year-to-year variability in Ghana’s production,” lead researcher Anna Lea Albright from Harvard told Mongabay via email. A flowering cacao tree in Ecuador’s Los Bancos Canton. Image courtesy of Pablo Leautaud via iNaturalist (CC BY-NC 4.0). Albright and her colleagues began looking into the issue in 2024, when global cacao prices surged after several poor harvests in West Africa. They considered several possible explanations for the trend, including aging trees, pests and diseases, gold mining, smuggling and weather. Analyzing daily rainfall and temperature records, the researchers noticed a pattern. Losses or gains during…This article was originally published on Mongabay