A Prequel to the Dantean Anomaly: The Water Seesaw and Droughts of 1302–1307 in Europe

Abstract. The cold/wet anomaly of the 1310s ( Dantean anomaly ) has attracted a lot of attention from scholars, as it is commonly interpreted as a signal of the transition between the MCA and the LIA. The huge variability that can be observed during this decade, similarly with the high interannual variability observed in the 1340s, has been highlighted as a side-effect of this rapid climatic transition. In this paper, we demonstrate that a multi-seasonal drought of almost two years occurred in the Mediterranean between 1302 and 1304, and respectively a series of hot and dry summers north of the Alps from 1304 to 1306. We propose to interpret this outstanding dry anomaly, unique in the 13th/14th century, combined with the 1310s and the 1340s cold anomalies, as part of the climatic shift from the MCA to the LIA. Our reconstruction of the predominant weather patterns of the first decade of the 14th century from documentary and proxy data lead to the identification of multiple European water seesaw events in 1302–1307, with similarities to the seesaw conditions which prevailed in 2018 over continental Europe. It can be debated to which extent the 1302–1307 period can be compared to what is currently discussed regarding the influence of the Arctic amplification phenomenon on the increasing frequency of long-lasting stable weather patterns that occurred since the late 1980s. Additionally, this paper deals with socio-economic and cultural responses to drought risks in the Middle Ages from contemporary sources and provides evidence that there is a significant correlation between blazes that devastated cities and pronounced dry seasons.