Objective drought and high flow catalogues for Europe

Regional drought and high flow characteristics vary spatially and temporally throughout Europe, and therefore objective classifications of drought and high flows are preferred in determining the variable regional characteristics of hydrological extremes. This study applies objective methodologies for defining regional droughts (Regional Deficiency Index; RDI) and high flow episodes (Regional High Flow Index; RHFI) to observed daily river flow timeseries from 579 stations across Europe, over the period 1961-2005. Drought and high flow catalogues are presented for 23 homogeneous European regions, allowing an assessment of the regional variation in the extent, duration, seasonality and spatio-temporal evolution of hydrological extremes in Europe.