Adaptation of Croatian Wine-growing Zones to Climate Changes

Most parts of Croatia are suitable for viticulture, but the choice of grape variety depends heavily on the temperature conditions of the areas and thus on the winegrowing regions and zones in which the areas are located. Since the last revision of the wine-growing zones, the temperature characteristics in Croatia have changed, making it necessary to revise the existing zones and regions. In this study, the changes of five biometeorological indices (Growing Degree-Days (GDD), Temperature Growing Season (TGS), Huglin Index (HI), Cool night Index (CI) and Dryness Index (DI)) were calculated at 80 stations of the Croatian Hydrometeorological Institute in the period 1961–2020 and in three CORDEX Regional Climate Models (RCMs) simulations for period 2041–2070. The observed and modelled data were spatially interpolated using regression kriging, assuming a linear relationship between the meteorological parameters and four predictors: Latitude, Longitude, Elevation and Distance from the Sea. The results show significant changes in the bioclimatic indices over the observed period, which were not always accompanied by administrative changes in the winegrowing regions and zones. As a result of climate change, there are also new areas suitable for viticulture, and climate model simulations indicate further changes and shihs in the regions and zones.