The purpose of this thesis is to evaluate the effectiveness of the thermal time descriptor Normal Heat Hours (NHH), in a climate change context, applied to the description of the viticultural systems based on the close relationship between thermal resources and plant phenology. In particular the research studies the way in which NHH has changed over time and the potential future changes due to climate of the vine in Sardinia over the next thirty years regarding cultivation and consequently concerning modification of the rural landscape. Recent studies show that models using NHH perform better than Degree-Day models, for all statistical indices tested and the dependent variables. Experimenting with different application methods of analysis, testing different thresholds, the thesis conducts a specific case study in region Nurra in order to generate maps of the region by applying an appropriate geo-statistical methodology and local phenological datas for many cultivars. The maps of meteorological data (i.e. temperatures, rainfalls), agro-meteorological
indices (Huglin, Fregoni) and Normal Heat Hours with different thresholds permit to understand how indices varied across the territory. Moreover the thesis simulates what may happen in 2050 for the wine sector in Sardinia appling a range of climate change scenarios developed by Goddard Institute for Space Studies, GISS and the 'Hadley Center of the UK Meteorological Office
