Modern Landfill Field Trip Friday (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.

Earth’s Water

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.

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.

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.

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.)

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)

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

Topography & Rain Shadow Effect

Global Precipitation Tropical Moisture; Coastal Moisture What about Continental Interiors?

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

The Water Cycle

Water Uses Consumptive vs Non-Consumptive

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

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

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

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

Surface Water Withdraws

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

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

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

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

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

Sinkholes: YIKES!

Saltwater Anyone?

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

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.

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

Activity Assignments: (choose one option) #8a) Wildlife Protection in Thailand Thailand #8b) Florida Everglades RestorationFlorida Everglades

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.