Group seminar on 19. January, 14:15 CET
Drought impacts in Spain, their links to meteorological drought indicators and predictability
Spain is a region that is greatly affected by droughts and because of global climate change, drought severity and frequency are predicted to increase. The consequences of drought and its impacts on society and the environment are becoming more important. Monitoring and early warning systems rely on several drought indicators; however, assessments on how these indicators are linked to impacts are still lacking. In this study, we explored the links between different drought indicators and drought impacts within six sub-regions in Spain. We used drought impact reports as impact data from the European Drought Impact Report Inventory database, and provided a new case study to evaluate these links. We proved that a region with a small sample size of impact data can still provide useful insights regarding indicator-impact links. As meteorological drought indicators, we used the Standardised Precipitation Index and the Standardised Precipitation-Evapotranspiration Index. We used a Standardised Soil Water Index and a Standardised Streamflow Index as agricultural and hydrological drought indicators, respectively. We also explored links between drought impacts and the teleconnection patterns, El Niño Southern Oscillation (ENSO), North Atlantic Oscillation (NAO) and the East Atlantic pattern, as well as global mean surface temperature (GMST). We conducted a correlation analysis and then tested the predictability of drought impacts using a Random Forest model, which proved to be skilful. Our results showed meteorological indices are best linked to impact occurrences overall, at long time scales. However, robust links were also found for agricultural and hydrological drought indices, depending on the sub-region. NAO and ENSO, aggregated at long time scales, were top predictors of impacts in the south of Spain. We also found GMST to be a top predictor in the centre of Spain at long time scales.