Projecting the impacts of climate change on the phenology of grapevine in a mountain area

Background and Aims: The strong link between climate and grapevine phenology suggests a potentially stronger impact of climate change on viticulture in climate-limited areas, including mountain zones. The aim of this work was to evaluate the potential effects of climate change on grapevine phenology and viticultural suitability in a mountain region. Methods and Results: Climatic projections were applied to phenological models to determine the effect on stages of budburst, flowering and veraison for Vitis vinifera cv. Chardonnay. Calibration and validation of the models had been previously carried out in the same alpine region. The output of the general-circulation climatic model HadCM3, run with two different Intergovernmental Panel on Climate Change emission scenarios, was statistically downscaled to 10 locations in different agricultural sites in Trentino, Italian Alps, some of which are presently unfit for viticulture due to climatic limitations. Results yielded a trend of phenological advance, with interesting differences among phases and sites. Simulated advance was more pronounced at higher elevations, and larger for veraison than for spring phenophases. Conclusions: As a consequence of the considerable warming projected by future climate scenarios, some mountain sites at about 1000 m were expected to fall within areas climatically suitable for viticulture before the end of this century. Nevertheless, noticeable differences from present conditions are not expected within a short timescale. Significance of the Study: These projections, suggesting a more pronounced phenological response at higher elevations, may support the development of adaptation strategies aimed at maintaining the profitability of mountain viticulture even in times of global change.