Understanding Earth's Water Cycle: Field Trip & Atmospheric Processes

1. Modern Landfill Field TripFriday (3-5 p.m.) From PSY go north on Albemarle St. to Mt. Rose; turn rt (east) onto Mt Rose; go about 5 mi; turn rt on Mt. Pisgah Rd. (at Turkey Hill Minit Market); Modern Landfill is on rt.

2. Earth’s Water

3. Water • The water cycle (hydrologic cycle): • Evaporation and transpiration (water vapor) versus condensation and precipitation (liquid/solid water). • What is water’s fate once on the Earth’s surface? • Human demands for freshwater resources. • Human impacts on the hydrologic cycle affect quantity and quality of the resource and ecosystems. • Getting more water versus conservation of existing resources.

4. Atmospheric Processes 1) Evaporation: water molecules move from liquid to gaseous state. Energy input required. • What’s transpiration? Is there an energy input? • Relative humidity: percent water vapor relative to the maximum at a given temperature. Hot air holds more water vapor. What if air cools? • Water purification results from evaporation and condensation; impurities are left behind.

5. 2) Condensation:It’s when water vapor concentrates to form liquid water; happens when relative humidity approaches 100%; requires an aerosol or surface for water to bind. Energy is released as heat and lost to space.

6. Condensation to Precipitation (3) • Adiabatic cooling: warm moist air rises to lower atm. pressure; expands and cools. • High relative humidity + aerosols = clouds • Increasing condensation = larger water droplets Gravity prevails and droplets fall (i.e. rain) • Atm. pollutants are carried by precipitation back to the Earth’s surface (e.g. acid rain nitric acid.)

7. Global Precipitation Patterns • Global precipitation distribution depends on patterns of rising and falling air masses. • Two main factors: • Global convection currents (winds) • Topography (rain shadow effect)

8. Trade Winds (easterlies) Westerlies (from west) Convection and Atmospheric Circulation Note latitudes of rising moist warm air compared to falling dry cool air.

9. Topography & Rain Shadow Effect

10. Global PrecipitationTropical Moisture; Coastal MoistureWhat about Continental Interiors?

11. Processes on the Earth’s Surface Gravity rules liquid and solid water! B D A C Runoff to Streams Uptake Groundwater Flow Infiltration

12. The Water Cycle

13. Water UsesConsumptive vs Non-Consumptive

14. Human Impacts on the Water Cycle • Changing the earth’s surface • Decreased infiltration • Increased runoff • Stormwater Mismanagement • Pollution • Withdrawal for use

15. Storm Water Mismanagement With development comes less infiltration capacity. Storm drainage is more “flashy”.

16. Other Consequences of Storm Water Mismanagement • Lower Baseflow • Increased pollution • Stream bank erosion

17. Water Pollution Runoff Pollutants: Fertilizers Pesticides Pet fecal matter Road salts Sediments Oil

18. Surface Water Withdraws

19. Consequences of Overdrawing • Surface waters: • Shortages (30% rule) • Ecological effects Wetland Loss:

20. Values of Wetlands:Ecosystem Services • Purify waters (nutrients and sediments) • Control floods • Protect shorelines from erosion • Recharge groundwater • Wildlife feeding and rearing habitat • Increases biodiversity • Aquatic • Terrestrial

21. Wetland Values - Economic • Pelt and skin harvesting (alligator) • Waterfowl hunting • Sport and commercial fishing • Timber harvesting (hardwood and cypress swamps) • Bird watching and wildlife photography • Recreation (hiking, boating) • Biological laboratory for students of all ages

22. Wildlife Dependence on Normal Stream Flow Coho Salmon (Oncorhynchus kisutch) • Warming of shallower stream waters; less oxygen. • Increased sediment deposition. • Migration interference of diadromous species.

23. Consequences of Overdrawing • Groundwater: • Falling water tables • Lower surface waters • Land subsidence • Saltwater intrusion Ogallala Aquifer: withdraw 100x recharge; 1/5 US agriculture

24. Sinkholes: YIKES!

25. Saltwater Anyone?

26. Getting More Water • Dam Construction • More evaporation • Habitat loss (up & down) • Disrupts fish migration • Water Diversion Projects • Wetland loss • Coastal ecosystem damage • e.g. Florida Everglades

27. Desalting Seawater Distillation: Boil water and condense water vapor; salts left behind (disposal?) Reverse Osmosis: Water is removed against its concentration gradient by use of high pressure pumps.

28. Using Less Water • Irrigation • Surge flow microprocessor • Drip irrigation • Municipal uses • Incentives and regulations limiting water use • Composting toilets • Gray water separation

29. Activity Assignments:(choose one option) #8a) Wildlife Protection in Thailand http://www.npr.org/programs/ #8b) Florida Everglades Restoration http://www.evergladesplan.org/ http://www.dep.state.fl.us/secretary/everglades/

30. Activity Assignment #8 Details • #8a) Thailand Wildlife Protection: • Listen to the series of three NPR broadcasts. • Write a paragraph that defines the problems of illegal wildlife trade. • Write a paragraph on the growing causes of the problem. • Write a paragraph that discusses solutions. • Include your perspective on the subject. • #8b) Florida Everglades Restoration: • Use both websites as resources. • Write a paragraph on the history of the water divergence problem. • Write a paragraph on the damage to the Everglade Ecosystem. • Write a paragraph on the restoration project as a solution. • Include your perspective on the subject.