A ∼700 years perspective on the 21st century drying in the eastern part of Europe based on δ18O in tree ring cellulose

Numerical simulations indicate that extreme climate events (e.g., droughts, floods, heat waves) will increase in a warming world, putting enormous pressure on society and political decision-makers. To provide a long-term perspective on the variability of these extreme events, here we use a similar to 700 years tree-ring oxygen isotope chronology from Eastern Europe, in combination with paleo-reanalysis data, to show that the summer drying over Eastern Europe observed over the last similar to 150 years is to the best of our knowledge unprecedented over the last 700 years. This drying is driven by a change in the pressure patterns over Europe, characterized by a shift from zonal to a wavier flow around 1850(CE), leading to extreme summer droughts and aridification. To our knowledge, this is the first and longest reconstruction of drought variability, based on stable oxygen isotopes in the tree-ring cellulose, for Eastern Europe, helping to fill a gap in the spatial coverage of paleoclimate reconstructions.

Automated summary

Based on a 700-year tree-ring oxygen isotope chronology from Eastern Europe and paleo-reanalysis data, it is found that the summer drying observed in Eastern Europe over the past 150 years is unprecedented in the last 700 years. This drying is driven by a change in pressure patterns over Europe, leading to extreme summer droughts and aridification.