Environmental Science 14th Edition by Tyler Miller ,Scott Spoolman

Exercise 17

What are the two key concepts for this section Define freshwater. Describe how water is recycled by the hydrologic cycle and how human activities can overload and alter this cycle. What percentage of the earth's freshwater is available to us Define groundwater, zone of saturation, water table, aquifer, surface water, surface runoff, watershed (drainage basin), reliable surface runoff, and drought. What percentage of the world's reliable runoff are we using and what percentage are we likely to be using by 2025 How is most of the world's water used Describe the availability and use of freshwater resources in the United States. Define water footprint and virtual water. What are five major problems resulting from the way people are using water from the Colorado River basin What percentage of the earth's land suffers from severe drought today and how might this change by 2059 How many people in the world lack regular access to clean water today and how high might this number grow by 2025