Hydrological Impacts of Climate Change

The increasing rate of the global surface temperature will have a significant impact on local hydrological regimes and water resources, which leads to the assessment of the climate change impacts. Main parameters that are closely related to the climate change are temperature and precipitation. Therefore, there is a growing need for an integrated analysis that can quantify the impacts of climate change on various aspects of water resources such as precipitation, hydrologic regimes, floods, drought, etc. There have been many studies of climate-change effects on hydrology and water resources which usually include: (a) use of climate models (GCMs), (b) use of downscaling techniques to model the hydrologic variables (e.g., precipitation) at a smaller scale based on large scale GCM outputs and (c) use of hydrological models for assessment of global climate change impacts. This paper reviews the existing methods for assessing the hydrological impact of climate change and discusses the challenges for future studies in this field.