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Europe is expected to experience major climatic shifts during the 21st century but the impact on agricultural productivity from such changes is uncertain. Here, we combine proxy, instrumental, and model data to assess interannual to multi‐centennial changes in central European agroclimate over the past 2,000 years and projections into the near future. Whereas early 21st century conditions are rare but not fully unprecedented, more than half of the area that was considered highly productive throughout the Common Era in central Europe currently falls outside of that definition. This trend will likely continue as even the most conservative climate projections push central Europe outside the range of past natural variability of changes to agroclimatic zones. Reconstructed extremes prior to the instrumental record align well with contemporary documentary records of societal upheaval. Forecasted changes to the main agroclimatic drivers require substantial adaptation in land use and agricultural management strategies of considerable costs. Plain Language Summary: Climate variability has a direct impact on agricultural productivity in Europe. However, to fully understand how this relationship may impact society in the future, we need long‐term records that encompass many different scenarios. We combine stable isotopes from tree rings, instrumental weather data, and climate projections for the future to study the changes occurring within the system over a period of 2,100 years. Periods in the past that experienced harsher agroclimate conditions coincide with societal change or events. The climate projections indicate that more than half of the high‐productivity land within the study region will experience worse conditions in the near future. Key Points: More than half of central European land categorized as highly productive in a long‐term context has lost this status due to droughtCentral European agroclimate is projected to move beyond the conditions of the past 2,000 years in upcoming decadesThree previous cases of poor agroclimate conditions have been associated with major societal downturns [ABSTRACT FROM AUTHOR]

Climatic warming from the last glacial maximum to the current interglacial period was punctuated by a ∼1300 years long cold period, commonly referred to as the Younger Dryas (YD). Several hypotheses have been proposed for the mechanism triggering the abrupt inception of the YD, including freshwater forcing, an extra-terrestrial impact, and aerosols from volcanic eruptions. Here, we use synchronised sulphate and sulphur records from both Greenland and Antarctic ice cores to reconstruct volcanic forcing between 13,200–12,800 a BP GICC05 (years before 1950 CE on the Greenland Ice Core Chronology 2005; GICC05). This continuous reconstruction of stratospheric sulphur injections highlights a ∼110-year cluster of four major bipolar volcanic signals alongside several smaller events just prior to the YD inception. The cumulative Northern Hemisphere aerosol burden and radiative forcing from this cluster exceeds the most volcanically active periods during the Common Era, which experienced notable multidecadal scale cooling commonly attributed to volcanic effects. The Laacher See eruption (LSE), recently redated to 13,006 ± 9 cal a BP, falls within our time window of study and has been proposed as a trigger for the YD but a direct volcanic imprint for the LSE in the Greenland ice cores has thus far proved elusive. Comparison of simulated sulphate deposition for mid- and high-sulphur LSE-type emission scenarios to the ice-core estimated sulphate deposition and interhemispheric asymmetry ratios allows several signals between 13,025 and 12,975 a BP GICC05 to be proposed as plausible candidates for the LSE. The magnitude and persistence of volcanic forcing directly preceding the YD inception highlights the need to consider stratospheric sulphur injections and their radiative forcing in future analyses and climate model experiments used to explore the mechanisms that triggered this or similar abrupt cooling events. • Volcanic forcing between 13.2–12.8 ka BP GICC05 reconstructed using ice-core records. • Greenland and Antarctic sulphate records and high-precision chronologies utilised. • Four bipolar signals in 110 years with radiative forcing exceeding key CE periods. • Reconstruction useful for exploring mechanisms that triggered the YD inception. • Several volcanic signals identified as candidates for the Laacher See eruption. [ABSTRACT FROM AUTHOR]