Global warming is causing earlier phenological dates for vines and changes in the quality of wines all around the world. To understand how vines are liable to react to future climate evolution, the climate of viticultural areas needs to be known as accurately as possible. In this article, temporal evolution and spatial variability of temperature in the wine producing area of the Loire Valley were analysed with a multi-scalar approach. First, the regional evolution of temperature and bioclimatic indices were studied over the past 60 years in the wine-producing area of the Loire Valley and showed a general warming at all locations in the regional weather station network (Météo-France). Secondly, temperature data from weather stations located within the vineyards between Angers and Saumur were studied for the year 2010 and underlined spatial variability of temperature between the different plots according to the different topoclimates. Finally, particular attention was paid to the Coteaux du Layon vineyards (sweet wine producing appellation) where 21 temperature data loggers were set up in the vine rows to study climate at local scale. The study showed, in particular, that the spatial variability of temperature and bioclimatic indices in these vineyards was greater than those observed at larger scales.

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