Abstract. Records of grape harvest dates (GHDs) are the oldest and the
longest continuous phenological data in Europe. However, many available
series, including the well-known (Dijon) Burgundy series, are error prone
because scholars so far have uncritically drawn the data from 19th century
publications instead of going back to the archives. The GHDs from the famous
vine region of Beaune (Burgundy) were entirely drawn from the archives and
critically cross-checked with narrative evidence. In order to reconstruct
temperature, the series was calibrated against the long Paris temperature
series comprising the 360 years from 1659 to 2018. The 664-year-long Beaune
series from 1354 to 2018 is also significantly correlated with tree-ring and
documentary proxy evidence as well as with the central European temperature
series (from 1500). The series is clearly subdivided into two parts. From
1354 to 1987 grapes were on average picked from 28 September on, whereby
during the last 31-year-long period of rapid warming from 1988 to 2018
harvests began 13 d earlier. Early harvest dates are shown to be
accompanied by high pressure over western–central Europe and atmospheric
blocking over Denmark. The 33 extremely early harvests comprising the fifth
percentile bracket of GHDs are unevenly distributed over time; 21 of them
occurred between 1393 and 1719, while this is the case for just 5 years
between 1720 and 2002. Since the hot summer of 2003, 8 out of 16 spring–summer
periods were outstanding according to the statistics of the last 664 years,
no less than 5 among them within the last 8 years. In the Paris temperature
measurements since 1659, April-to-July temperature reached the highest value
ever in 2018. In sum, the 664-year-long Beaune GHD series demonstrates that
outstanding hot and dry years in the past were outliers, while they have become
the norm since the transition to rapid warming in 1988.