The North Atlantic Oscillation affects the quality of Cava (Spanish sparkling wine)

This study explores the possible effects of the North Atlantic Oscillation (NAO) on the quality of Spanish Cava. We found a significant negative relationship between the mean NAO for the months of March through August of each year between 1970 and 2008 and the probability of obtaining a top quality Cava. The NAO is associated with temperature and rainfall variations in the Cava region, which affect vine physiological processes during grape maturity. The probability of obtaining a top quality Cava was highest when the mean value of the NAO was negative, which causes the mean temperature in the Cava area to decrease, with positive consequences on Cava quality. Although the overall discrimination capacity and explanatory power of the model were low, 80 % of clearly favorable years were classified correctly as corresponding to top quality Cava, and 70 % of clearly unfavorable years were classified correctly as non top quality Cava.