Influence of the interannual variability of meteorological drought on the cross-interactions of ecological and hydrological drought in the central spanish pyrenees

This paper analyzes the influence of the interannual variability of climatic drought on ecological and hydrological droughts for a basin in the central Spanish Pyrenees using variables derived from observations and hydro-ecological simulation in order to determine the possible connection between meteorological, ecological and hydrological drought considering a cascading approach and encompassing different variables that give insights into water availability in the basin (e.g., soil moisture, streamflow, reservoir storages and releases). Using different climatic, ecological and hydrological standardized drought indices, we show the greater role of meteorological droughts in hydrological systems than in ecological systems, and the small influence of vegetation activity and growth in explaining the interannual variability of water resources in the basin. By contrast,hydrological droughts are strongly affected by precipitation variability with relationships characterized by seasonal differences and the role of different time-scales in the standardized drought metrics.