Chapter 11 Water

Two kinds Salt water Freshwater We can only live a few days without water, but we can live a month without food

The water cycle Continuous movement of water between earth and its atmosphere Is water a renewable resource?

Global water distribution What percent of earth is covered by water? About two thirds, or more specifically 71% What percentage of that water is salt water? 97% So 3% of water on earth is fresh water Most of this is ICE (77%) A lot is GROUNDWATER (22%) Less than 1% is SURFACE WATER (that we can drink)!

Chapter 11 Water Mr. Turri

 Fresh water on Earth’s land surface ◦ Remember we said less than 1% of Earth’s water is surface water!  Sources of fresh water in the form of surface water include : ◦ Rivers ◦ Streams ◦ Lakes

 A flowing network of rivers and streams draining a river basin ◦ Other rivers and streams flow into other rivers and streams…making a larger river.

 The area of land that is drained by a river  Biggest in the US in the Mississippi

 Most of the freshwater available for human use cannot be seen – it exists underground  When it rains some water goes into the streams and rivers, but most of it percolates down through the soil and into the rocks below  This water is called groundwater

 As you travel down through the earths surface, eventually you reach a point where the soil is saturated with water, this is the water table.

 Aquifer: underground formation that contains groundwater  Porosity: the percentage of total volume of a rock that has spaces (pores)  Permeability: the ability of rock or soil to allow water to flow through it

 An area of the Earth’s surface from which water percolates down into an aquifer