Enhancing climate change impact assessment in viticulture by resolving microclimates

Climate change poses significant challenges to viticulture, particularly by affecting vineyard phenology, yield, and grape quality. This study highlights the role of microclimate modelling in improving vineyard management, using the climate-water-soil-plant nexus. High-resolution climate downscaled data (10 m spatial resolution) generated by the NicheMapR microclimate model, coupled with the STICS soil-crop model, provide accurate phenological and yield predictions for two Portuguese vineyards: "Quinta do Bomfim" (Douro wine region) and "Herdade do Esporao" (Alentejo wine region). The NicheMapR microclimate model captures fine-scale environmental variables to simulate vineyard-scale parameters under historical (1981-2010) and future (2041-2070 and 2071-2100) climate scenarios. Following Representative Concentration Pathways (RCPs) 4.5 and 8.5, shifts in key phenological stages, such as flowering, fruit filling, maximal leaf area index, physiological maturity, and harvest, along with yield changes, were analysed. Results reveal earlier phenological events, shortened growth periods, and significant yield declines, particularly under the high-emission scenario RCP8.5. The findings highlight the value of microclimate modelling in understanding and adapting to climate-induced changes, providing a framework for precision agriculture and agronomic modelling. This approach significantly reduces climate change risks, sustains vineyard productivity, and fosters a climate-resilient wine sector.