Wine Quantity and Quality Variations in Relation to Climatic Factors in the Tokaj (Hungary) Winegrowing Region

Abstract

The effects of climatic elements on wine quantity and quality for the winegrowing region of Tokaj-Hegyalja, Hungary, were analyzed. By applying the Makra test, significant breaks were detected in both the wine quantity and wine quality data sets. Analysis of the relationship between climatic variables and wine quantity and quality, using different statistical methods, confirmed that the most important factors of wine quantity are hours of sunshine in May, June, July, and August and precipitation in September. For wine qualilty, mean temperature, precipitation, and hours of sunshine in May and September play key roles in addition to precipitation in July and hours of sunshine in August. The role of climate in September is most important, since aszú (<i>Botrytis</i>) formation, as an important component of wine quality, depends largely on conditions during September. Results indicate that the significant variables obtained by factor analysis better explain linear relationships between climate and wine quantity and quality than those obtained by the χ² test. Seven objective vintage climate types were defined using the methods of factor and cluster analysis. Results show that the classification of vintage climate types is more effective in explaining variations in wine quantity than variations in wine quality. Overall, the research identifies the characteristics and importance of the climatic variables with significant relationships with wine quantity and quality in the region. The results are useful in applying quantity and quality assessment strategies for wine production in the region.