The influence of climatic variability on the quality of wine.

In this paper, the quality of the wine from the Dão (Viseu) region of Portugal is examined and relationships between wine quality and climatic variability are obtained using spectral and correlation analysis to determine the structure of the temporal variations. The spectra of the series of quality of wine values show statistically significant oscillations coherent with those found in the series of teleconnection indices. The series cover a period of 33 years. A significant correlation was obtained between wine quality and minimum air temperature in May, December and total precipitation in April. The teleconnection circulation indices are used to provide some physical insight into the most significant oscillating components of the climatic and the wine quality series. We found significant and positive correlations between the quality of the wine and the Southern Oscillation Index (SOI) of August and negative with the SOI of January and with the North Atlantic Oscillation of April. Wine quality and climatic series can be predicted using statistical models depending on significant oscillations.