ES 100 Lecture Notes - Lecture 9: Water Cycle, Rain Shadow, Water Scarcity
Document Summary
Uneven water supply distribution: water and precipitation are unevenly distributed around the globe, rain falls unevenly across the earth"s surface, three principal factors control global water deficits and surpluses, global atmospheric circulation, proximity to water sources, topography. Global ocean currents: ocean currents act as a global conveyor system, redistributing warm and cold climates around the globe. The physical makeup of the ocean is complex: currents, vast riverlike flows in the upper 1,300 feet, driven by wind, heating/cooling, gravity, density differences, and the coriolis. Ocean currents affect earth"s climate: movement of ocean water affects global climate, thermohaline circulation. Europe: water cools, becomes saltier through evaporation and then sinks, creating a region of downwelling. Frozen water: glaciers, ice and snow, 2. 4% of the world"s water is classified as fresh, 90% is held in glaciers, ice caps, and snowfields, climate change is shrinking glaciers and snowfields. Groundwater: groundwater is the second largest reservoir of fresh water.