Volcanic activity has a critical influence on viticulture, significantly impacting wine production through its broader effects on climate, as evidenced by new scientific research focusing on the Moselle Valley during the Middle Ages.
The study, published in the journal Climate of the Past, highlights the importance of climate in winemaking, specifically regarding temperature, precipitation, and aridity. Warmer and drier climates with extended growing seasons generally benefit grapevine growth. However, there exists a tipping point beyond which such conditions can be detrimental, particularly in Mediterranean regions.
Researchers from the University of Stockholm’s history department and the Bolin Centre for Climate Research investigated the Moselle Valley, a historic wine-producing area encompassing north-eastern France, south-western Germany, and eastern Luxembourg. Their analysis aimed to understand the impact of volcanic eruptions on viticulture, particularly through climate cooling.
The research team examined the effects of volcanic eruptions on viticulture from 1444 to 1786. They utilized tax records to determine the number of wine barrels produced, alongside stratospheric sulfur data derived from Greenland and Antarctic ice cores and climate reconstructions based on dendrochronology, the study of tree-ring patterns which provide insights into historical temperature and precipitation.
Volcanic eruptions release aerosols that reflect solar radiation and serve as nuclei for cloud formation, resulting in cooler surface temperatures. The study identified a consistent pattern of reduced wine production in the years following significant volcanic events, contrasted with higher production levels during warmer, drier periods.
The researchers pinpointed specific years—1481, 1601, 1674, 1767, and 1784—immediately following volcanic eruptions, where no tax was recorded on wine production, indicating reduced harvests. They also found that wine production declined for three to four years after more intense sequences of eruptions.
The study’s authors concluded: “Robust and highly significant wine production declines occurred in the years immediately following major volcanic events. Warmer, and to a lesser extent drier, climate conditions had a moderately strong, but persistent, positive effect on wine production. We also find a volcanic cooling signature in spring and summer in temperature reconstructions.
“However, the detected volcanic signature in the Moselle Valley wine production is considerably stronger than the one found for Central Europe in tree-ring data and is instead more akin to the strong volcanic signature present in Fennoscandian tree-ring series. On the basis of our findings, we encourage further compilation, publication, and analyses of additional wine production series containing unique biological and climatic information.”
This research underscores the significant role volcanic activity plays in shaping climate conditions that affect viticulture, providing valuable insights into historical and future wine production challenges.
