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The Water Cycle. The Water Cycle. The Water Cycle. The Water Cycle. DB2. The Water Cycle. Evaporation: liquid to gas salt/impurities in water are left behind Condensation: gas to liquid fresh water
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The Water Cycle • The Water Cycle
The Water Cycle • DB2
The Water Cycle • Evaporation: liquid to gas • salt/impurities in water are left behind • Condensation: gas to liquid • fresh water • clouds • Precipitation: release of fresh water
The Water Cycle • Animation video youtube
The Water Cycle • Saltwater 97% • Freshwater 3% • 2/3 or 2% over oceans • 1/3 0r 1% over land • Glaciers 85% • Runoff 1% • Groundwater 14%
Runoff • Runoff Rivers, streams, lakes, etc. • Ancient civilizations • Niles river, Egypt • Mesopotamia, Iraq
Runoff • What are the different ways that sediments are transported by Runoff?
Runoff • Modes of Sediment Erosion • Solution Dissolved Sediments salts • Suspension floating clay, silt • Bed load dragged and rolled pebble, gravel • Saltation suspended and bed load sand
Runoff • What factors can affect the carrying capacity of runoff?
Runoff • Carrying Capacity Factors • Speed/Energy • Slope Head water vs. Base level • Channel shape Straight vs. Curved • Channel bed surface Smooth vs. Rough • Volume of water
Runoff • Why do rivers slow down? • Run out of energy • Reach flat areas base level, no gravity pull • Hit a barrier rocks, dam • Enter a body of water lake, ocean
Runoff Deposition • What happens to their sediment load when rivers slow down? • Release sediments • Sorted deposits • Larger grains gravel, pebble, and sand • Smaller grains last silt and clay
Runoff Deposition • Sorted sediment deposition
Runoff Deposition • Sediments released by rivers at their Base level create depositional formations that resemble triangles. • Depending on the location of base level • Deltas • Alluvial Fans
River's Base level ends in a body of water. Ex. Mississippi Gulf of Mexico Ex. Nile River Mediterranean Sea Delta
River’s Base level ends on land. Alluvial Fan
Review • What are the 4 modes of sediment erosion? Solution, Suspension, Bed load, & Saltation • How does a sediment’s grain size affect its mode of erosion? • finer grain ~ suspended • Coarser grain ~ saltation/bed load • Compare and contrast a river’s head water and base level, in terms of location and channel slope. • Head waters where runoff originates steep slope • Base level where runoff terminates gentle slope
Review • Which of the two types of the river channels allow faster currents? Straight OR Meandering/curved • How would the river bottom affect the water current? • Rough/irregular ~ slower current • Smooth/less friction ~ faster current • What is the primary force behind why rivers flow? • Gravity • What can we infer from the flow direction of a river? • Slope of the land.
Review • What happens when a river reaches its base level? • It slows down and releases its sediments. • In what order of grain size are sediments released ? • Coarse to fine grain • Gravel to clay • Sorted deposits • What 2 depositional features may form at the rivers’ base levels? Delta ( water) Alluvial Fan ( land )
Stream Divides & River Systems Lab • Map with rivers
Runoff • Divides and Drainage Basins (Watersheds)
Rivers & Streams • Head waters where runoff originates steep slope • Base level where runoff terminates gentle slope
Runoff • Watershed and Drainage basin
Glaciers • Perito Moreno Glacier in Argentina
Groundwater • Groundwater
Do Now Questions • How is freshwater replenished on Earth? • What % of earth’s total water at any time is freshwater? • What is the most available source of fresh water?
Groundwater • 1/11/12 • Objectives • Where and how does groundwater form? • Exploring topics • How is groundwater affected by human activity? • Homework • SGCM: 10.1 Groundwater
Groundwater • Groundwater 14% of freshwater • The most available source of freshwater. • Aquifer • Soil or rock that has the potential to contain groundwater.
Groundwater • Porosity ~ % sediment pore space • higher porosity=more water • Permeability ~ capability to permit water movement higher permeability= faster flow • Aquifer ~ soil/rock • high Porosity & Permeability • * Sandstone and Limestone
Groundwater • Aquifer: Porous & Permeable • Precipitation • surface Infiltration • Zone of Aeration • air & water soil moisture • water table • Zone of Saturation • 100% water • Groundwater Impermeable layer Clay/Shale
Exploring GW Issues • Fresh Groundwater ~ Renewable Resource • Excess usage vs. Replenishing • Depletion ~ reduction in supply • Potentially Non-renewable Resource Water Cycle
Exploring GW Issues • U.S. Freshwater aquifers • High Plains Aquifer • Glacial ice-melt 30,000 yrs. ago • Excess usage • Depletion by 1/4 • Dried up wells!
Exploring GW Issues • Depletion near saltwater seas/oceans • Saltwater Intrusion Lower density Higher density
Exploring GW Issues • Saltwater Intrusion
Exploring GW Issues • Intrusion of saltwater/harmful substances • Pollution • Groundwater no longer a resource. • Surface and underground sources of pollution
Exploring GW Issues • Excessive GW usage • Loss of water pressure • Soil compaction • Land subsidence • Markers 1925, 1955, 1977
Review • What is an Aquifer? • Soil/rock: High Porosity and Permeability • Has the potential to contain groundwater. • Name 2 rocks that can be good aquifers. • Sandstone and Limestone • Compare and contrast the two zones of an aquifer. • Zone of Aeration ~ water and air in pores • Zone of Saturation ~ water in pores ~ Groundwater
Review • How is fresh groundwater replenished in nature? • Precipitation: rain, melting snow • What happens to the thickness of groundwater as more water infiltrates into an aquifer? • Thickness increases. • What will happen to the water table level as more water seeps into an aquifer? • It will rise/gets closer to the surface
Review • Shale and clay act as impermeable layers at the base of aquifers. What other rock type(s) can create the same condition? Explain why. • Igneous • Metamorphic • Low-No porosity and permeability
Review • Describe underlying conditions that can cause saltwater intrusion in a freshwater well. • Near saltwater sea/ocean • Excessive withdrawal than natural replenishing of GW. • Name possible effects of groundwater depletion in New Jersey? • Wells dry up! • Land subsidence • Saltwater Intrusion
Review • Homework: SGCM: 10.1 Groundwater
Groundwater • df