The HydrosphereCh. 4, Sec. 2

Water for Agriculture:• Irrigation:

– Artificial watering of crops

Water for Industry:

• Industrial uses:– Ingredient of products– Acts as a coolant &

lubricant for machines– Power source (Hydroelectricity)

Hydroelectricity:

Water for Transportation:• Most efficient method of moving bulk cargo

Threats to water supply: • Over population &

• Pollution

Characteristics of H2O:• Water = Earth’s ONLY substance that can exist

as a , , or .

• Dissolves ALMOST anything over time– Chemical weathering

• Heats & cools slowly (moderates temps)

World water distribution:

• Oceans: 97%

• Frozen: >2% Freshwater: <1%

THE HYDROLOGIC CYCLE:• The circulation of water throughout the hydrosphere• Water is ALWAYS changing form & location

What drives the hydrologic cycle?• Solar Energy

• Wind

• Gravity

1) EVAPORATION:

2) CONDENSATION:

3) PRECIPITATION:

Precipitation can accumulate as snow or ice

4) RUNOFF of water thru rivers & streams, stored in lakes, &

eventually returns to the ocean:

5) Also,the ground absorbs water.

6) TRANSPIRATION:• Water vapor given off by plant leaves

7) EVAPOTRANSPIRATION:

• Combined evaporation of H2O from the ground w/transpiration by plants

Summary of Hydrologic Cycle:• Evaporation, Condensation, Precipitation

1) Desalinization:The purification of salt water into fresh water

2) Headwaters:• the first/smallest streams to form from runoff

3) TRIBUTARY:• a smaller stream/river that flows into a larger

stream/river

4) Watershed/Drainage Basin:• area of land that is drained by a river & its

tributaries

5) Estuary:

• Semi-enclosed body of freshwater & seawater (rich in fish & shellfish)

6) Delta: formed at the mouth of a river where sediment accumulates

Mississippi River Delta (Bird’s foot delta)

Nile River Delta (Arcuate delta)

7) Lake: body of water located in a basin surrounded by land on all sides

Great LakesCaspian Sea

Crater Lake, OR

Lake Baikal, Russia

8) GROUNDWATER:--water found below ground in spaces betw.

rocks & soil

9) Water table:--the level at which all the spaces are filled

w/water (the top of the saturated zone)

10) AQUIFER:--where groundwater flows thru layers of rocks

The Ogallala Aquifer:*Makes farming in the Great Plains possible

*Water table dropping due to overconsumption

The Oceans:• Cover 72% of Earth

• Divided into four oceans– Pacific (Earth’s biggest geographic feature)– Atlantic– Indian – Arctic (smallest)

• Depths vary…

The Mariana Trench:*subduction boundary

*deepest place on Earth (>36,000 ft deep)

• Video

Continental Shelf:• Where continental surfaces extend under the

shallow ocean water around continents

Characteristics of Seawater

• 1) Contains every element

• 2) Salts are most common (3.5%)

• 3) Does not have temp extremes

• 4) Always circulating