Earth’s Oceans

By PJ, Mitchel, Karly, and Sophie

Compounds in the Ocean

Sodium chloride is the most abundant dissolved solid in the ocean

Oceans

71%

Pacific, Atlantic, Indian, Arctic, Southern

Salinity

Salinity is the measure of dissolved salts in a given amount of liquid

PPT(parts per thousand)

Increased through evaporation

Decreased through added water

Density

More salinity= more density

Evaporation= more density

Added water= less density

Deeper/colder= denser

Functions

Regulates temperatures at different locations of the earth

Absorbs and releases thermal energy more than dry land masses Keeps earth at a temperature

suitable for life

Chapter 2 ~ Section 2

Amaan, Patrick, Anna, & Emma

Exploration of the Ocean Floor

Sonar: Stands for sound navigation and ranging. Technology is based off the echo-ranging behavior of bats. It used to calculate the depth of the ocean

Satellite: Satellites from space send images back to Earth which can then be used for studying the speed and direction of ocean currents

GeoSat: A military satellite used to measure changes on ocean height

Piloted Vessels: (Ex) Alvin and Deep Flight. These vessels allow the ocean floor to be studied with people inside it.

Robotic Vessels: (Ex) Jason II and Madea. This vessels allow even more deeper exploration that is controlled robotically, without people.

Continental Margin

Subdivided into the shelf, slope, and rise

Continental Shelf Slopes gently toward the open ocean

Location: between the shoreline and the continental slope

Continental Slope Steeply inclined section

Location: between the continental rise and the continental shelf

Continues down to flattest part of the ocean

Continental Rise Base of the continental slope

Gently sloping

Location: between the continental slope and abyssal plain

Deep-Ocean Basin

Composed of oceanic crust

Abyssal Plain: A broad, flat, almost level area of the deep–ocean basin

Covered by mud and remains of small decomposing marine organisms

Average Depth: 4,000 meters

Ocean Trench: A steep, long depression in the ocean floor that runs parallel to a chain of volcanic islands or a continental margin

Occur where one oceanic plate is subducted beneath a continental plate or another oceanic plate at a convergent boundary

Seamount: A submerged mountain made up of of volcanic material on the ocean floor

At least 1,000 meters tall

Form where magma pushes upwards through or between tectonic plates

Volcanic Island: Seamounts that surpass sea level

Passive Margins vs. Active Margins

Active Margins Passive Margins Occurs on active plate boundaries

Earthquakes occur often here

Lots of volcanoes

Ex. West Coast (California)

Occurs where there is no active plate boundaries

No trenches, volcanoes, seamounts and earthquakes are not common

Ex. East Coast of the U.S.

Chapter 3 Section 1

By Caleigh, Lilly, Gabrielle, and Rachel

Global Winds

Uneven heating of Earth

Equator vs. Polar Regions High-pressure and low-pressure systems

Convection currents

Coriolis Effect = curving of wind direction

Global winds and wind belt

Wind Flow and Interaction

Northern Hemisphere Clockwise

Southern Hemisphere Counter-Clockwise

From high to low

Surface currents

Surface temps El Niño Global Wind

Flow

Coriolis Effect

Curving of objects from a straight path Wind and surface currents move in curved paths

Caused by Earth’s rotation

Northern- clockwise

Southern-counterclockwise

Goes from high to low pressure

Deep Currents

Deep currents- A streamlike movement of ocean water far below the surface

Not controlled by the wind

Affected by the oceans temperature and Salinity Salinity is the amount of dissolved solids in a liquid

Decreasing temperature and increasing salinity increases waters density

How they form

Decreasing temperature Cold air cools the water molecules causing them to slow down and move closer together

Causes volume to decrease and become denser

Increasing Salinity through freezing When ice forms on top of the water, the dissolved solids are squeezed out

This increases salinity and increases density

Increasing Salinity through evaporation When water is evaporated it leaves behind dissolved solids

This makes the water denser

How currents work

Surface currents carry warm less dense water to the polar regions

Warm water replaces colder dense, water that sinks to the ocean floor

Deep currents carry colder water along the ocean floor to polar regions

Water from deep currents rise and replace surface currents

Ocean Layers and Currents

By Jaycee Blythe and Caroline Whinney

Temperature Zones

Surface Zone

Thermocline

Deep Zone

Surface Zone

Warm, top layer

300 meters below sea level

Sunlight heats top 100 meters Mixes with cooler water below

Surface Zone

Thermocline

Second layer

300 meters to 700 meters

Temperature drops faster than other two zones

Thermocline

Deep Zone

Bottom layer

From 700 meters down

Cold, unchanging temperature 1-3 degrees Celcius

Deep Zone

Surface Currents

What controls their movement?

Causes of Surface Currents

Global Winds Coriolis Effect

Continental Defection

Global Winds Caused by uneven heating of the Earth which leads to differences in pressure

Coriolis Effect

StraightCurved

Continental Deflection

Movement of Surface Currents in Hemispheres

Science Chapter 3.2: Oceanography

Surface Currents, Climate, Upwelling, El Nino

Surface Currents/Climate

Surface Currents Horizontal, stream-like movement of water that occur near or at the surface of the ocean

Caused by global winds, continental deflection, and the Coriolis affect

Climate Weather in a area over a long period of time

Effects of Surface Currents on Climate

Temperatures of surface currents vary based on location

Warm-Water Currents: Warmer climate: increased humidity

Cold-Water Currents: Colder climate: drier atmosphere

The Gulf Stream current transports warm water from the equatorial region to the British Isles, warming the previously cooler climates of the North Atlantic

The California Current keeps the climate along the West cooler than inland climate year round

El Niño

El Nino: a change in the water temperature in the Pacific Ocean that produces a warm current

Causes of El Nino Produced every 2-12 years due to a reduction in intensity of the Trade Winds

Less warm water is transported from the southern Pacific to the western Pacific

Negative Ramifications There is no upwelling on the coast of South America

The coast of South America becomes deficient in nutrient-rich material

The western Pacific undergoes a series of droughts and experiences cold conditions

The eastern Pacific is subject to heavy precipitation

Significance Scientists can prepare the denizens of coastal regions that irregular weather is to be expected

Upwelling

Upwelling: a process in which cold, nutrient-rich water from the deep ocean rises to the surface and replaces warm surface water Upwelling is initiated by global winds blowing warm surface currents out to sea

When cold water rises to replace the warm water, it brings up nutrient-rich material with it that benefits plankton, and in turn, nekton

Chapter 3, Section 3

Waves Erin McGovern and Olivia Luff

Parts of a wave

Amplitude- ½ of the wave heightCrest- the highest point of a wave.Trough- the lowest point of a wave.Wave height- the vertical distance between the crest and trough of a wave.Wave length- the distance between two adjacent wave crests, or wave troughs.

Why do waves change as they approach the shore and how?

• Deep water waves become shallow water waves when they reach depths of less than ½ their original wavelength.

• Volume remains the same; consequently, the wave height must increase.

What are waves on the surface of the Earth caused by?

Surface current- a horizontal movement of ocean water that is caused by wind and that occurs at or near the ocean’s surface.

Causes:

The Coriolis effect- the Earth’s rotation causes wind and surface currents to move in curved paths rather than in straight lines.

Continental deflections- when the surface currents meet continents, the currents deflect, or change direction.

Global winds- Different winds cause currents to flow in different directions.

Tsunami

Tsunami- a giant ocean wave that forms after a volcanic eruption, submarine earthquake, or land slide.

Causes:

Volcanic eruptions, submarine earthquakes, and land slides cause the trigger of tsunamis.

How are tsunamis different from wind driven waves?

Tsunamis are created from seismic activity, while normal surface waves are effected by global winds, the Coriolis effect, and continental deflections.

Tides

Abbey Iafolla, Julia Gleason, Lauren Achenbach, Emma Osilka

What are tides?

Daily changes in level of ocean water

Regular pattern

High Tide Water advances towards shore

Low Tide Water recedes from shore

High Tide

Low Tide

How Often do Tides Change?

Change four times per day

Two high tides

Two low tides

What causes tides?

Gravitational pull of moon and sun

Earth’s rotation

Greater influence: Moon Closer to Earth

High Tides Water faces moon

Creates a bulge on both sides due to speed of Earth’s spinning

Low Tides Water is drawn away from other areas

Less gravitational pull

Takes 24 hours, 50 minutes for Earth to face moon again

Spring and Neap tides

Neap Tides Occur twice a month

First and third quarter

Causes: low high tides and high low tide

Sun, moon, and Earth form right angle

Spring or Neap Tide occurs every 7

days

Spring TidesOccur twice a month Full and new moonCauses: highest high tide and lowest low tideSun, moon, and Earth are aligned

What Are Tidal Bulges

Water is pulled towards Moon

Earth’s rotation causes bulge

Causes low tides in between two high tides