Lesson 1.1 pg. 1-6. The Blue Planet Nearly ¾ of the Earth’s surface is covered with water – 97% of the water on Earth is salt water – Remaining 3% is.

Lesson 1.1 pg. 1-6

The Blue Planet

• Nearly ¾ of the Earth’s surface is covered with water– 97% of the water on Earth is salt water – Remaining 3% is freshwater

• Water can exist in three forms– Solid (Ice)– Gas (Water Vapor)– Liquid

The Water Cycle

• The three forms of water move through the environment via the water cycle

• There are several major processes of the water cycle– Evaporation- changes water from a liquid to a gas– Condensation- when water vapor cools to return to a

liquid– Precipitation- When liquids or solids fall from the

clouds– Transpiration- when plants release water vapor from

their leaves into the air

The Water Cycle

Groundwater

• Runoff is precipitation that runs off the ground

• Groundwater is water stored beneath the Earth’s surface– 22% of Earth’s freshwater is groundwater– Used for drinking water, daily household,

agricultural, and industrial needs– Accessed through wells

Groundwater Natural Contaminants

• Groundwater is closely monitored for contaminants– Contaminants come from natural resources• Occurs when groundwater dissolves certain minerals

– Example: Hard water results from high concentrations of calcium

– Contaminants give water a disagreeable color, taste, and smell

Groundwater Affected by Humans

• Humans can contaminate groundwater– Not properly installed septic tanks– Pesticides and fertilizers from farms– Landfills– Chemical spills– Salt used on roads during icy conditions

*The quality of PA’s groundwater = GOOD!*

Surface Water

• Lakes and ponds hold ½ the liquid fresh water on the Earth’s surface- Rivers hold about 1% - Remaining fresh water is trapped in the Earth’s soil

Bodies of Water

Stream Characteristics• The place where any stream or river begins is called

the source• The place where a stream or river ends by flowing

into another body of water is called the mouth– Laminar flow occurs when water moves in a straight

path – Turbulent flow occurs when water movies in tiny circular

paths

Stream Characteristics: Velocity

• Velocity is the distance water flows during some period of time– Determines if flow will be laminar or turbulent – Quick flow = turbulent Slow flow = laminar

• Velocity determines the kind and amount of sediment that the water can carry

Stream Characteristics: Sediment Load

• There are three types of sediment load– 1. Dissolved load- dissolves some of the minerals

that make up the Earth’s surface

– 2. Suspended load- is sediment such as silt and clay that is in suspension

– 3. Bed load- sediment carried along the bottom of the channel such as sand, gravel, pebbles, and boulders

Stream Characteristics: River Deposits

• Rivers deposit sediment when velocity decreases– Deposits called bars form when a river slows down– Deposits can also form from overflow or flood• A flood plain is the part of the river valley that is covered

during a flood

Major Drainage Patterns

• Drainage Patterns of rivers and their tributaries, or feeder streams, depend largely on topography (physical characteristics of land0

• There are four types of drainage patterns – 1. Dendritic Drainage– 2. Radial Drainage – 3. Rectangular Drainage– 4. Trellis Drainage

Dendritic Drainage Pattern

• This type of drainage resembles mature trees– The main river or stream is similar to a tree’s

trunk– The tributaries form the tree branches

• Dendritic Drainage forms where bedrock is uniform and massive– Ex. Plains region

Radial Drainage Patterns

• Forms when streams flow from a high central area – Plateau or volcanic mountain

• Resembles spokes of a bicycle tire

Rectangular Drainage Pattern

• Form when bodies of rock are broken by a series of faults and fractures

• Bends in rectangular drainage form right angles

Trellis Drainage Patterns

• A type of rectangular pattern in which tributary streams are nearly parallel to each other

• Form when sections of softer, nonresistant rock alternate within sections of harder, resistant rock

Complete the Lesson ReviewPg: 6

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