chapter 15 earth science

Wave

A rhythmic movement that carries energy through space or matter (such as ocean water).

Western coasts of continents in the Trade Wind belts

Areas where upwelling exists

Forward

As an ocean wave passes, water moves up and down in a circular pattern and returns to it original position. Only the energy moves in this direction.

Density currents

Current caused by differences in temperature and salinity of ocean water; move slowly in the deep ocean.

Crest

Highest point of a wave

Wave Length

Horizontal distance from crest to crest

24 hours and 50minutes

How long does a daily cycle of 2 high tides and 2 low tides take?

photosynthesis

Light penetrates only the upper loom of seawater. ____________ of marine plant life occurs here!

Trough

Lowest point of a wave

3.5%

On average, what percent of seawater is dissolved salts?

96.5%

On average, what percent of seawater is water?

Ways Salts is Removed from seawater

Percipitation (fall to the bottom), The salty spray from breaking waves creates droplets which are carried away by the wind; Marine organisms remove calcium to build their shells, bones and teeth.

Dynamic Equilibrium

Salinity of seawater does not increase because as salts are being deposited, they are also being removed.

Highest Salinity

Subtropical areas where evaporation exceeds percipitation

Variations in Salinity

The amount of salts in the seawater varies from place to place.

Evaporation and Precipitation

The average percent of seawater that is water and the average percent of seawater that is dissolved salts varies from place to place in the ocean. It depends on the amount of these two things.

Wave Base

The depth to which the wave disturbs the water

Salinity

The measure of the amount of dissolved salts in sea water is called ________ ? It is expressed as grams of salt per kilogram of seawater or as parts per thousand (3.5% or 3.5ppt).

Upwelling Deep Water

The trade winds blow surface water offshore and the surface water is replaced by this. These waters are rich in nutrients.

Wave Height

The vertical distance between the crest and the trough. It depends on wind speed, wind duration, and fetch.

Sun and Moon

They have a gravitational effect on the tides.

Upwelling

This is the upward motion of water in the ocean.

Outgassing of water vapor from inside the earth: extraterrestial water from commets and meteorites

What are the two theories of formation?

crest, trough, wave length and wave height

What do ocean waves have?

Oceans

What has existed almost since the beginning of geologic time?

fetch

What is the expanse of water over which the wind blows called?

Tides

What is the periodic rise and fall of sea level (caused by the gravitational pull on the earth's water by the moon and to a lesser extent, the sun) called?

wind speed, the wind duration and fetch

What is wave height dependent upon?

71%

What percent of the earth"s surface is covered by water?

3%

What percent of the earth's water is freshwater?

97%

What percent of the earth's water is seawater found in oceans and seas?

Neap Tides

When the earth moon and the sun form a right angle. The difference between high and low tides is not as great.

Higher than normal high tides and lower than normal low tides

When the earth, the moon and the sun are alligned, the gravitational attraction of the sun and the moon create this.

Spring Tides

When the moon is either new or full, the earth and the sun are aligned. Higher than normal high tides and lower than normal low tides.

Lowest Salinity

Where freshwater rivers empty into the oceans

Frozen in the polar caps in glaciers

Where is most of the earth's fresh water found?

where freshwater rivers and streams flow into the ocean

Where is the percent of seawater less salty?

Where freezing is occuring

Where is the percent of seawater more salty?

Surface currents

Wind driven, occur in the upper few hundred meters of the ocean.