Our understanding of the impact of climate change on global coffee production is largely based on studies focusing on temperature and precipitation, but other climate indicators could trigger critical threshold changes in productivity. Here, using generalized additive models and threshold regression, we investigate temperature, precipitation, soil moisture and vapour pressure deficit (VPD) effects on global Arabica coffee productivity. We show that VPD during fruit development is a key indicator of global coffee productivity, with yield declining rapidly above 0.82 kPa. The risk of exceeding this threshold rises sharply for most countries we assess, if global warming exceeds 2 °C. At 2.9 °C, countries making up 90% of global supply are more likely than not to exceed the VPD threshold. The inclusion of VPD and the identification of thresholds appear critical for understanding climate change impacts on coffee and for the design of adaptation strategies.

我们对气候变化对全球咖啡生产影响的理解主要基于对温度和降水的研究，但其他气候指标可能引发生产力的关键阈值变化。在这里，我们使用广义加性模型和阈值回归，调查温度、降水、土壤水分和蒸汽压力不足 (VPD) 对全球阿拉比卡咖啡产量的影响。我们表明，果实发育期间的 VPD 是全球咖啡生产力的关键指标，产量在 0.82 kPa 以上迅速下降。如果全球变暖超过 2°C，我们评估的大多数国家/地区超过此阈值的风险都会急剧上升。在 2.9 °C 时，占全球供应量 90% 的国家更有可能超过 VPD 阈值。