Kenyan tea is made with heat and water: how will climate change influence its yield?

Abstract

Tea is the most consumed beverage in the world apart from water. Climate change is anticipated to affect the tea industry, but quantified large-scale predictions of how temperature and water availability drive tea production is lacking in many regions. Here, we use satellite-derived observations to characterize the response of tea yield to water and heat stress from 2008 to 2016 across Kenya, the third largest producer of tea. We find that solar-induced fluorescence captures the interannual variability in tea yield remarkably well (Pearson’s correlation coefficient, r = 0.93), and that these variations are largely driven by the daily dynamics of soil moisture and temperature. Considering rising temperature in isolation suggests that yields in 2040–2070 would decrease by 10% relative to 1990–2020 (ranging between −15% to −4% across 23 models), but most climate models also simulate an increase in soil moisture over this interval that would offset loss, such that yields decrease by only 5% (ranging between −12% to +1%). Our results suggest that adaptation strategies to better conserve soil moisture would help avert damage, but such changes require advanced planning due to the longevity of a tea plant, underscoring the importance of better predicting soil moisture over the coming decades.