EARTHSC 2WW3 Study Guide - Final Guide: Humus, Soil Horizon, Subsoil
10 Apr 2012
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Document Summary
24 million km3 of the freshwater in the world is in the form of ice and permanent snow cover. 10 million km3 is what we can actually use. 96% of the glaciers are located in greenland and antarctica, 4% are located in glaciers and mountainous icecaps. Which continents have the largest amount of ground water. States that have a scarcity index of above 1 are: Underground water delivery system found in middle east, north africa and southwest asia. Long tunnels up to 45 km long and connected by several shafts up to 120m deep. Uses gravity to deliver water from a higher water source. Delivers 1. 5 million l of water to rome. Allowed population growth, which lead the development of irrigation canals to supply egypt with water from the nile. Oldest known canal was built in mesopotamia in 4000 bce and was built to connect cities. Another old canal was in north india built in 2600 bce.
