t Impacts on water resources produced by climate change can be exacerbated when occurring in regions
already presenting low water resources levels and frequent droughts, and subject to imbalances between water
demands and available resources. Within Europe, according to existing climate change scenarios, water resources
will be severely affected in Spain. However, the detection of those effects is not simple, because the natural variability
of the water cycle and the effects of water abstractions on flow discharges complicate the establishment of
clear trends. Therefore, there is a need to improve the assessment of climate change impacts by using hydrological
simulation models. This paper reviews water resources and their variability in Spain, the recent modelling studies
on hydrological effects of climate change, expected impacts on water resources, the implications in river basins
and the current policy actions.