Global maps of canopy photosynthesis of wine grape under changing climate

Abstract Climate change induces shifts in suitable areas for cultivation and phenology of grapevines, which regulate complex sunlight patterns within hedge rows and canopy photosynthetic gain. However, suitability assessments have focused on climate indices, such as growing season temperature, but have ignored canopy photosynthesis, despite its close connection to berry yield and wine quality. Here, we visualized global maps of the theoretical maxima of grapevine canopy photosynthetic gain during berry development under present and future climates scenarios using an integrated model of canopy light interception, leaf thermal balance, and photosynthetic processes. The high-latitude zone accommodated high-gain sites under future scenarios, characterized by shifted suitable areas and elevated atmospheric CO2 concentrations. By contrast, at some prestigious sites located at low latitudes, the projected leaf temperatures exceeded the optimal range for photosynthesis, resulting in reduced gain. Our results highlight a north-south gradient in canopy photosynthesis and support the decision-making of winemaking stakeholders.