Records of dates of harvest and yield for European viticulture have been kept for nearly a thousand years (Penning- Rowsell, 1989) revealing periods with more beneficial growing season temperatures and greater productivity. During the medieval “Little Optimum” period (roughly 900–1300 AD) vineyards were planted as far north as the coastal zones of the Baltic Sea and southern England, and during the High Middle Ages (12th and 13th cen- turies) harvesting occurred in early September as compared to early to mid October today(Pfister, 1988; Gladstones, 1992). Conversely, dramatic temperature declines during the “Little Ice Age” (14–19th centuries) resulted in most of the northern vineyards dying out and growing seasons that were so short that harvesting grapes in southern Europe was difficult.
Climate change impacts on viticulture have been and are likely to be highly variable, both geographically and varietally. An early analysis suggested that in Europe, growing seasons should lengthen and that precipitation would increase in the North and decrease in the South