Rainfall extremes drive cocoa yield losses across the tropics

Nearly six million smallholder farmers depend on cocoa for their primary income. Production shortfalls threaten this livelihood, yet the causes of these shortfalls are poorly understood. This study shows heavy rainfall is the dominant climatic constraint on cocoa yields across producing regions. By identifying heavy rainfall during flowering and early pod development as a recurrent source of yield loss, this work shifts attention from average climate trends to extreme events relevant for management and adaptation. Because rainfall extremes are partly predictable from large-scale patterns such as El Niño, and are expected to increase with warming, these results highlight an opportunity to assess crop-climate risks. Extreme precipitation may represent an underappreciated risk for perennial tree crops under increasingly variable hydroclimate conditions.