A Drought Alert system based on seasonal forecasts

Water resources are under stress in many areas of the world, because of a combination of climatic and anthropogenic factors. The Mediterranean area is one of the regions mostly vulnerable to climate alterations. These alterations have direct impacts on the surface water balance and groundwater recharge, and thus changes in the reservoir inputs and the management of water utilities (WUs) are severe challenges for water resources in the future. However, WUs management routines scarcely consider climate information and are based on the stationarity assumption, working on weekly or daily time scale. The use of seasonal forecasts for guiding a strategic planning of the resources has been increasing across several climate-sensitive sectors, including water management and energy. This is due to the fact that it is generally preferred to focus on the upcoming season rather than taking decisions on the basis of a 100-year climate projection. The project EUPORIAS promoted the use of climate information for decision support by involving both providers and potential users of seasonal data. It was demonstrated that seasonal forecasts may give important contributions in the fields of drought-risk assessment and mid-term reservoir management. This study aims at providing some insights in using seasonal forecasts to derive supporting information for water management decision-makers based on drought assessment. Indeed, the exploitation of climate information as precipitation in a mid-term scale, as the seasonal scale, allows for understanding the possible shifts in water resource availability. In this study we describe some results obtained for a case study in Greece.