CR prepress abstract  -  doi: 10.3354/cr01449

Environmental drivers of historical grain price variations in Europe

Jan Esper*, Ulf Büntgen, Sebastian Denzer, Paul J. Krusic, Jürg Luterbacher, Regina Schäfer, Rainer Schreg, Johannes Werner

*Email: esper@uni-mainz.de

ABSTRACT: Grain price (GP) volatility has been a central constituent in Europe commerce with fluctuations of barley, rye and wheat prices carefully documented over centuries. A thorough understanding of the climatic and environmental drivers of long-term GP variations is still limited, however. Here, we present a network of historical GP records from 19 cities in central and southern Europe for the 14th to 18th centuries. Spatial variability at inter-annual to multi-decadal scales within this network is compared with reconstructed warm-season temperatures and hydroclimatic conditions. We show that European GP’s are tightly coupled with historical famines and that food shortages coincide with regional anomalies in summer drought. Direct correlations between historical GP and reconstructed drought indices are low, hardly exceeding r = -0.2. Yet if the analysis is focused on extreme events, the climatic controls on high frequency price variations become obvious: GPs were exceptionally high during dry periods, and exceptionally low during wet periods. In addition we find GP variations were affected by temperature fluctuations at multi-decadal timescales. The influence of summer temperatures is particularly strong over the 1650-1750 period, subsequent to the Thirty Years’ War, reaching r = -0.40 at the European scale. This observation is supported by the lack of correlation among regional GP clusters during the period of hostilities, and increased inter-regional correlation thereafter. These results demonstrate that the exchange of goods and spatial coherence of GP data in Europe were controlled both by socio-political and environmental factors, with the latter being more influential during peacetime.