Gross primary productivity analyses suggest higher ENSO-mediated impacts in lowland cacao areas compared to mountain coffee regions in Latin America

Agroforestry systems in Latin America and the Caribbean cover millions of hectares and are potentially vulnerable to the El Niño-Southern Oscillation (ENSO). Using a correlational approach, we examined the climatic impacts of eight El Niño and La Niña events (1992-2020) on potential coffee and cacao growing areas estimated from species distribution models. Remotely sensed canopy and subcanopy Gross Primary Productivity data (GPP) were used as a proxy for idealized two-layer agroforestry systems. Correlations with six terrestrial climate variables indicated that exposure to El Niño was ubiquitous for both potential crop zones. Hotspots where GPP decreases in both canopy and shade vegetation during El Niño and La Niña events were found mostly in Central America, Northern South America, the Western Amazon and in coastal Brazil, for both crops. Outside these zones, coastal Brazil and the southern Mata Atlântica showed a complex response to ENSO variability, particularly for potential coffee areas where increased temperatures and humidity can boost GPP. Our results raise concerns about the vulnerability of agroforestry systems, especially in potential lowland cacao areas of the Amazon, as dry El Niño events may exacerbate ongoing climate change impacts.