Ch 23.1 Water & the Water Cycle

EARTH IS UNIQUE – ITS TEMPERATURES & PRESSURES ALLOW FOR WATER TO EXIST IN ALL THREE STATES: SOLIDS, LIQUID, AND GAS

Ch 23.1 Water & the Water Cycle

WATER MOVES THROUGH EARTH’S ATMOSPHERE, BODIES OF WATER, AND LAND IN THE WATER CYCLE.

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TRANSPIRATION

Most of our drinking water comes from GROUNDWATER (wells) and Surface Water Reservoirs (Lakes)

Video: http://www.cbsnews.com/stories/2010/01/08/eveningnews/main6073416.shtmVideo: http://www.msnbc.msn.com/id/21494919/ns/us_news-environment/t/crisis-feared-us-water-supplies-dry/l

Watersheds and Water Quality

Watershed: an area of land (and all of the streams, lakes, etc on it) that drain into a particular river system.Watersheds are divided by mountains or ridges.

What degrades water quality in a watershed?

1. IMPERVIOUS SURFACES impact WATER QUALITY

Surfaces like concrete or road that prevent water from

soaking into the ground (infiltrating).

As water moves through layers of rock, soil, and

leaves it is purified. More impervious surface less filtering

of groundwater poor water quality

Watersheds and Water Quality

Watersheds and Water Quality

2. IMPERVIOUS SURFACES impact FLOODING

Surfaces like concrete or road that prevent water

from soaking into the ground (infiltrating).

More impervious surface less ground water

more run off going into streams flooding

more erosion

Watersheds and Water Quality

3. Point & Non-Point PollutionPoint Pollution: Pollution (chemicals, fertilizers, bacteria, etc) from a SPECIFIC SOURCE/Location.Examples: •Mercury from an oil refinery•Hexoflourine from a power plantNon-Point Pollution: Cannot pin-point source; Mutliple sourcesExamples: •Motor oil from road surfaces•Pesticides/fertilizers from lawns, farms, or golf courses•Fecal bacteria from farm animals•Pharmacueticals flushed into waste water.

Watersheds and Water Quality

3. Point & Non-Point PollutionPoint & Non-point pollution enter water supply by:

1.Carried by RUN-OFF that joins streams/rivers. (Pesticides, Fertilizers)2.INFILTRATES GROUND WATER.

Ground Water Terms (MCP)

AQUIFER = A large porous rock layer that serves as a ground water source . People use aquifers for drinking water and agriculture (watering crops).

SPRING = A place where groundwater is bouncing back to the surface.

Ground Water Concepts and Terms

Permeable Rock (Porous) = Limestone or Sandstone- Allows water to flow through and stores water like a sponge-Make up AQUIFERS (Large underground water storage that people use for agriculture or personal wells)

Impermeable Rock = Slate or Granite-Does not allow water to easily pass through- Underlies permeable layers to make SPRINGS (where water bounces back to the surface from the ground).

Ground Water Concepts and Terms

Unsaturated Zone= Layers of rock where there is room for more water. There are still air spaces.

Saturated Zone= Layers of rock that are completely filled with water. No air spaces.

Water Table = Top of the saturated zone; Rises after rain/ Drops during drought.

Ch 23.2 Weathering & Erosion

Weathering

• Process of chemically changing or physically breaking down rock.

• Water and wind weather rock.

• Weathering happens on the surface.

ErosionErosion = process that wears down and

carries away rock and soil fr. one place to another

Agents of Erosion (What’s doing the erosion?):

• Water – streams, rivers, oceans, glaciers

• Wind

• Gravity

End product of erosion = SOIL or SEDIMENT

TYPES OF Weathering

• Mechanical: physically break down rocks into smaller fragments.

A. Frost wedging

B. Abrasion

C. Plant roots

• Chemical: Chemical reactions dissolve minerals in rock

Acid rain

Plant roots: Physically break apart rock layers

Abrasion – water / wind carries sand & rocks over surface & smoothes it (sand blasting)

Examples or Mechanical Weathering

and expands

Expanding ice

Hoodoos were created by frost wedging over a long period of time

Examples of Chemical Weathering

1. ACIDIC RAIN WATER will dissolve calcium containing rocks (limestone, & marble). This is how caves are made.

2. Oxidation (chemical reactions w/ O2) of Iron containing rocks (Makes rust)

Iron reacts w/ oxygen to make blue soil.

Red rock layers formed by iron reacting w/

oxygen

Caves form when limestone is dissolved

by acidic water

Weathering & Climate

Chemical Weathering & Climate

• Carbonic acid weathers rock and particles usually end up on the bottom of the ocean floor..

• Carbonic acid forms when CO2 is dissolved in water. This CO2 comes from the ATMOSPHERE.

• More chemical weathering = More CO2 removed fr. Atmosphere.

• When “NEW” land is exposed to Earth’s surface, weathering rates increase; temps. Decrease.

• Mt. Building exposes new land.

Rates of Weathering depend on…

1. Temperature – Warmer temps. Increase chem. Weathering / Alternating freezing & warm temps. increase mech. Weathering.

2. Availability of Water – More water, more weathering

3. Type of Rock – Calcium containing rocks (limestone, calcite, marble) are prone to chemical weathering

Mass Movements= Erosion w/ help of gravity. Once weathering has broken rock up, gravity can move rocks down slopes! (H2O usu. helps)

• Land slides – rapid, large amounts of rock & soil

• Mudflows – rapid, large amounts of soil, sediments & water

• Creep – gradual, soil moves down slope (alt. freezing & cold temps)

• Slump – rapid, small amount of hillside move down a “step” (Wet soil)

Types of Mass Movement (aka, mass wasting)

More rain means greater chance of mass movement

Creep

Slope

Landslide