The knowledge of river flow regimes has a capital importance for a variety of practical applications, in waterresource management, including optimal and sustainable use. Hydrological regime is highly dependent on climaticfactors, among which the most important is surely the precipitation, in terms of frequency, seasonal distributionand intensity of rainfall events. The streamflow frequency regime of river basins are often summarized by flowduration curves (FDCs), that offer a simple and comprehensive graphical view of the overall historical variabilityassociated with streamflow, and characterize the ability of the basin to provide flows of various magnitudes.Climate change is likely to lead shifts in the hydrological regime, and, consequently, in the FDCs.Staring from this premise, the primary objective of the present study is to explore the effects of potential climatechanges on the hydrological regime of some small Mediterranean basins. To this aim it is here used a recenthydrological model, the ModABa model (MODel for Annual flow duration curves assessment in ephemeral smallBAsins), for the probabilistic characterization of the daily streamflows in small catchments. The model has beencalibrated and successively validated in a unique small catchment, where it has shown a satisfactory accuracyin reproducing the empirical FDC starting from easily derivable parameters arising from basic ecohydrologicalknowledge of the basin and commonly available climatic data such as daily precipitation and temperatures. Thus,this work also represents a first attempt to apply the ModABa to basins different from that used for its preliminarydesign in order to testing its generality.Different case studies are selected within the Sicily region; the model is first calibrated at the sites and then forcedby future climatic scenarios, highlighting the principal differences emerging from the current scenario and futureFDCs.The future climate scenarios are generated using a stochastic downscaling technique based on the weather generator,AWE-GEN. This methodology allows for the downscaling of an ensemble of climate model outputs derivingthe frequency distribution functions of factors of change for several statistics of temperature and precipitationfrom outputs of General Circulation Models (GCMs). The stochastic downscaling is carried out using simulationsof GCMs adopted in the IPCC 5AR, for the future periods of 2046-2065 and 2081-2100.
|Numero di pagine||1|
|Stato di pubblicazione||Published - 2015|