water cycle, groundwater, water pollution
TRANSCRIPT
Water Cycle, Groundwater,
Water Pollution
Hydrologic Cycle
http://www.mnforsustain.org/water_climate_global_water_cycle_study.htm
Distribution/Cycle Animation
Water Cycle
• 86% of evaporation from sea surface• 14% of atmospheric moisture from
EVAPOTRANSPIRATION
• 78% of precipitation on sea surface• 22% of water precipitated falls on land
http://meted.com/mesoprim/mpradfog/print.htm
Water Cycle
Water Cycle
• Less that 3% of Earth’s water is on land• Over ¾ of that is in glacial ice• Most of the rest is stored as groundwater
– (some groundwater is saline)
Water Distribution
Groundwater
• Precipitation infiltrates Earth’s surface• Largest reservoir of liquid fresh water• Drinking water source for half of U.S.
Water sources in Oregon
http://www.deq.state.or.us/wq/dwp/dwp.htm
Groundwater
Surface water
Groundwater
• Contributes to stream flow• ‘Universal solvent’• Dissolves some rock types
– Limestone (CaCO3)– Salts (NaCl, KCl)– Gypsum (CaSO4)
Groundwater Source
• First becomes ‘soil moisture’– Plants use it– Some evaporates directly– Some sinks down
• Infiltration• ‘Groundwater’ is stored
Groundwater Terms
• Zone of saturation• Water table• Zone of aeration
Groundwater terms diagram
Groundwater Storage
• Porosity of rock– Spaces between sand grains– Cracks in crystalline rock– Dissolved cavities
• Permeability– Allows water to move– Interconnection of pore spaces
• Stored in AQUIFER– Porous and permeable rock
• Trapped by AQUITARD– Impermeable rock– Clay, shale
Groundwater Storage
Groundwater Movement
• Very slowly—– Small openings– High surface tension
• Pressure forces water to areas of lower pressure– Hydraulic gradient– Hydraulic head
Groundwater movement diagram
Springs
• Where water table intersects ground surface
Photo of cliff springs
Carlsbad Caverns
Arecibo, Puerto Rico: Radio Telescope in Sinkhole
Karst drainage of manmade lake in Missouri
Karst towering buttes
http://en.wikipedia.org/wiki/Yangshuo
Thailand Karst Towers
http://www.siue.edu/GEOGRAPHY/ONLINE/Gillespie.htm
Hot Springs
• Water heated by hot rock (cooling magma)• Temperature increases solvent capabilities• May contain acids from magmatic water
Geysers
• Special type of hot spring• Pressure of water column suppresses
boiling• Heat added eventually overcomes
pressure• Sudden rise of water, increase pressure
release on rising
Old Faithful photoOld Faithfulwebcam link
http://www.nps.gov/archive/yell/oldfaithfulcam.htm
Geyser Eruption
Geyser eruption stages
Wells
Wells after drawdown
Artesian wells
Ogallala supported agriculture
Ogallala Aquifer
• Exploited in Great Plains agriculture
• Water table dropped
• Recharge rate low
San Joaquin Valley subsidence
Not able torecover dueto aquifercompaction
Water Drop
http://www.wested.org/pblnet/exp_projects/H2O.html
Contaminated Groundwater
Groundwater purification
Agriculture sources of groundwater contamination
Landfill leachate contamination
Drinking Water Standards
Parts per Million
• ppm• Change
1,000,000 mg to litersmg 1,000,000
mg 1
L 1mL 1,000
L 1g 1
mL 1mg 1,000
g 1mg 1,000,000 =×××
L 1mg 1
ppm 1 =
Sewage treatment
Primary sewage treatment
Secondary sewage treatment
Natural substances in water
Impurities in Runoff
• Atmosphere• Dissolved substances• Silt, etc.• Radon
Organic byproducts in water
Contamination of Water• Micro-organisms• Decay products• Plant nutrients• Petroleum compounds• Acid• Industry• Mining
Drinking water standards
Pollution Sources
Raw Sewage discharge
http://www.nwri.ca/sande/nov_dec_2002-e.html
Plant nutrient pollution
http://www.na.fs.fed.us/SPFO/pubs/n_resource/riparianforests/Tab%20I.htm
Agricultural Runoff
http://www.na.fs.fed.us/SPFO/pubs/n_resource/riparianforests/Tab%20I.htm
Oil pollution
http://www.intertanko.com/tankerfacts/sizes/pollution.htm
Mine leachate
http://www.ew.govt.nz/enviroinfo/hscs/contam/
Water Pollution
http://www.jvkco.com/digidare/water.html
Water Pollution Prevention
http://www.jvkco.com/digidare/water.html
Drinking water standards