Chapter 15: Earth's Oceans Study Guide

What are the stages of Mass Movement in order?

1.) Sea ice forms during the winter. 2.) Salt ions accumulate beneath the ice. 3.) Cold, salty water sinks. 4.) Salty water begins to migrate along the ocean floor toward the equator.

What are the layers of the Ocean in order?

1.) The Surface layer 2.) The Thermocline 3.)The Bottom layer

What is the average depth of the oceans?

3,800 m.

_____ percent of seawater is dissolved salts.

3.5%.

How much of the Northern Hemisphere is covered by oceans?

61%.

How much of the Southern Hemisphere is covered by the oceans?

81%.

Sonar

A Device that uses echoes to map features of the ocean floor.

The 'TOPEX/Poseidon'

A Satellite used to monitor the ocean's surface temperatures.

Density Current

A current caused by differences in the temperature and salinity of ocean water.

The 'Alvin'

A submersible used to study the deep oceans.

Neap Tides

A type of tide that occurs when the sun, the moon, and the Earth form a right angle.

Spring Tides

A type of tide with the highest high tides and the lowest low tides.

Gravitational and centrifugal forces

Forces exerted by the sun and the moon that generate tidal bulges.

Approximately 3% of Earth's water is located here:

Frozen Ice Caps, rivers, lakes, and underground sources.

Global Sea Level

Has risen and fallen by hundreds of meters in response to warm periods and ice ages. It slowly rises at 3 mm per year.

The Earth's Oceans

Have existed for almost 4.6 billion years.

What factor would cause higher rates in the salt content of surface ocean water?

High rates of evaporation and low rates of precipitation.

In what direction do the gyres of the northern hemisphere circulate?

In a clockwise direction.

Tectonic Forces

Lift or lower portions of the seafloor, and also affect the sea level.

In addition to salts _____ is dissolved in seawater as well.

Nutrients.

The ______ contain 97% of the water found on Earth.

Oceans.

Tide

Periodic rise and fall of sea level.

This salt is the most abundant in seawater

Sodium Chloride.

What is the rhythmic movement of a wave?

Steadily forward moving circles.

This Ocean extends from more than 20,000 km from North to South

The Atlantic Ocean.

The three major Oceans are:

The Atlantic, The Pacific, and The Indian.

Which ocean is the largest?

The Pacific Ocean.

Salinity

The amount of dissolved salts in seawater.

Tidal Range

The difference between high tide and low tide.

The 'Challenger'

The first ship to use sophisticated measuring devices to study the ocean.

The Crest

The highest point of a wave.

Wave length

The horizontal distance between the top of one wave and the top of the next. Determines the depth to which the wave disturbs water.

The Trough

The lowest point of a wave.

Oceanography

The scientific study of Earth's oceans.

Parts per thousand (ppt)

The unit of measurement most commonly used to measure the salt content of water.

Upwelling

The upward motion of ocean water. They originate from the bottom of the ocean and are cold. They exist mainly in areas off the western coasts of continets in the trade-wind belts. The trade winds blow surface water offshore, and the surface water is replaced by _____ deep water. These waters are rich in nutrients, which support abundant marine life populations.

Wave height

The vertical distance between the highest and lowest point of a wave.

Due to what natural process is water still being added to the Earth's hydrosphere?

Through Volcanism.

What contributes to keeping the total amount of water on Earth the same even after all these years?

Ultraviolet Radiation.

Ocean water moves horizontally and _____.

Vertically.

What gases are emitted by volcanoes?

Water vapor and carbon dioxide.

Wave Breaker

When the water depth becomes less than one-half of a wave's wave length when it's in shallow water, it causes changes to the movement of water particles at the base of the water. That makes the waves slow down. When this happens, incoming wave crests catch up with the slower wave crests, and the waves become unstable. Then their crests collapse.

What is one way scientists can determine the difference in Earth's Oceans from early on, and compare them to our oceans today?

By comparing modern-day seashells to prehistoric seashells.

What is a known source of Earth's water?

Comet impacts.

This process removes salt from seawater

Evaporation.