Reliability Issue in Projections of the Impacts of Climate Change and Other Changes on Water ResourcesWater Research and Management

Important hydrological changes, or generally water resources changes, are being observed in Serbia, as well as in many other parts of the world. Many national and international projects and studies address climate change and its impact on water resources. Some focus solely on the impact of climate change, while others also assess the impact of land use changes and/or changes in human use of water. Generally, the majority of the outcomes of these projects and studies tell us not only that the availability of water resources in Serbia will decrease, but that there may also be significant differences between catchments. Even within a single catchment, depending on the climate and hydrological models used, the differences between the results of the initial and other assumptions made, and the impacts assessed can be small but often significant. The reliability of the projections receives little or no consideration. This paper discusses this topic and attempts to provide some guidelines.