Climate Change Impacts on Surface Water Quality

Abstract

Climate change affects water resources through changes in evaporation, groundwater recharge, temperature, runoff and rainfall. Such changes affect the mobilization of nutrients, distribution and mobility of pollutants in freshwater systems. The direct and indirect climate change impacts on water quality comprise biological, physical and chemical changes. Biological changes include pathogenic microbes in water. Physical changes include increased water temperature, reduced river and lake ice cover, more stable vertical stratification and less mixing of water of deep-water lakes, and changes in water discharge, affecting water level and retention time. Chemical changes include increased nutrient concentrations, water color and decreased oxygen content. However, few scientific works have been recently published on the impacts of climate change on water quality modification. This chapter fills a real gap because there has been no comprehensive review on climate change and river water quality to date. It focuses on the expected water quality impacts of climate change.