Climatic shifts in high quality wine production areas, Emilia Romagna, Italy, 1961-2015

In the presented work, daily observations of minimum and maximum temperatures and precipitation—spatially interpolated in a high-resolution grid (5 × 5 km)—were used to detect climate shifts in the viticultural appellation areas of the Emilia-Romagna (ER) region, in the periods 1961-1990 and 1986-2015. The growing season (April to October) minimum, mean, and maximum temperatures were significantly increased in the second period compared to the first over the majority of the ER. Precipitation did not differ significantly, with the exception of certain small northeastern areas of the ER. The detected changes affected the ER viticultural environment in several ways: (1) an increase in the number of days with maximum temperature exceeding 30°C, which can induce plant stress; (2) changes in starting and ending dates of the climatologically defined growing season, dates of the first fall frost and the last spring frost, and length of the frost-free period; (3) shifts of most vineyard areas from ‘Region 2/Region 3’ to ‘Region 3/Region 4’ (according to the Winkler Index); (4) shifts of the majority of the grape-producing zones from ‘temperate/warm temperate’ to ‘warm temperate/warm’ (according to the Huglin Index); (5) decreased availability of soil water, which is necessary for grapevine development.