Exploring the added value of a long-term multidisciplinary dataset in drought research – a drought catalogue for southwestern Germany dating back to 1801

Abstract. Droughts are multidimensional hazards that can lead to substantial environmental and societal impacts. To understand causes and impacts, multiple variables need to be considered. Many studies identified past drought events and investigated drought propagation from meteorological droughts via soil moisture to hydrological droughts and some studies have included the impacts of these different types of drought. Here, we analyse different droughts and their impacts in a regional context using a multidisciplinary approach and compiled a comprehensive and long-term data set to place recent drought events into a historical context. We assembled a dataset of drought indices and recorded impacts over the last 218 years in southwestern Germany. Meteorological and river-flow indices were used to assess the natural drought dynamics. In addition, tree-ring data and recorded impacts were utilized to investigate drought events from an ecological and social perspective. Since 1801, 20 extreme droughts were identified as common extreme events when applying the different indicators. All events were associated with societal impacts. Our multi-dataset approach provides insights into similarities but also the unique aspects of different drought indices and highlights the unprecedented frequency and severity of droughts in the 21st century.