ENV200H1 Lecture Notes - Lecture 21: Fossil Water, Water Scarcity, Oak Ridges Moraine
Document Summary
Importance of groundwater: global availability of water, canadian usage of water, basic daily water requirement. Hydrologic cycle: water is continuously cycling through the environment. Ocean: the earths water supply remains constant, but humans alter the cycle of that fixed supply. Global hydrologic cycle is driven by: net evaporation over oceans, net precipitation over land. Surface water: streams, rivers, lakes, ponds, reservoirs, wetlands, runoff replenishes surface water, watershed. Area of land drained by a single river. Drainage basin: canada has 5 ocean watersheds. Gulf of mexico (water can drain northward) Groundwater: supply of fresh water found under earths surface, stored in underground aquifers, discharged into rivers, springs, etc , usually considered nonrenewable. Groundwater use and problems: out of sight, one-fifth of earths freshwater supply, jurisdictional boundaries, ex: ogallala aquifer. One of the largest reservoirs in the world, located in the usa (stores water from last glaciation over 10,000 years ago) Provides irrigation for much of the great plains states.