BIG IDEA: Studying oceans helps scientists learn about global climates

MAIN IDEA: The global ocean consists of one vast body of water that covers more than two- thirds of Earth’s surface.

 Identify methods used by scientists to study Earth’s oceans. 1. Challenger – 1 st ship in 1800’s to study the oceans 2. SONAR – sound navigation and ranging 3. Alvin – submersible that travels to the bottom of the ocean (up to 4500 meters deep)

 Discuss the origin and composition of the ocean 1 st Hypothesis: 1. comets and meteorites carried water to early earth 2. they contain about 0.5% water 3. pounded early Earth when Earth was still largely molten on the surface

 2 nd Hypothesis:  Volcanism brought water up to the surface from inside the Earth  Volcanoes release water vapor, CO 2, and other gases that make up the atmosphere

 Describe the distribution of water at Earth’s surface 1. 97% of water on Earth is salt water and is found in the oceans 2. 3% of water on Earth is freshwater found in : ◦ Icecaps ◦ Groundwater ◦ Rivers ◦ Lakes

Oceans have distinct layers of water masses that are characterized by temperature and salinity.

 Identify the chemical properties of seawater ◦ Salinity – amount of dissolved salts in seawater  Measured in ppt – parts per thousand  35 ppt OR35‰OR3.5%

 Subtropical Regions – evaporation rate is high ◦ Salinity - 37 ppt  Equatorial regions – precipitation rate is high ◦ Salinity - 32 ppt  Estuaries – where large rivers empty into the oceans ◦ Salinity varies with the tidal cycle

 Estuary

 Identify the physical properties of seawater ◦ Density : 1.02 g/cm 3 to 1.03 g/cm 3 More salt = more dense  Freezing Point: -2°C or 28°F  Light Absorption: light penetrates the top 100m ◦ Red light – does not penetrate past 10m ◦ Blue light – travels about 250m

 Illustrate ocean layering ◦ Thermocline – temperature decreases rapidly with depth

 Describe the formation of deepwater masses ◦ Deepwater masses move from the North and South poles to the equator ◦ As sea ice is formed the oceans becomes saltier ◦ Salty and cold water sink below the sea ice and travel to the poles

MAIN IDEA: Waves and currents drive the movements of ocean water and lead to distribution of heat, salt, and nutrients from one region of the ocean to another.

 Describe the physical properties of waves Describe the physical properties of waves ◦ Wave – a rhythmic motion/movement that carries energy through space or matter ◦ Ocean waves – created by wind blowing over water ◦ Energy moves forward, but water moves in a circular pattern

 As waves move into shallow waters, breakers form

 Explain how tides form ◦ Tides – periodic rise and fall of sea level  Influenced by the gravitational pull of the Sun and the Moon Spring TideNeap Tide -very high, high tide-average high and low tide -very low, low tide

 Compare and contrast various ocean currents  Surface Currents ◦ The top 100 m -200 m ◦ Move about 100 km per day ◦ Global wind systems push the surface currents

 Gyres ◦ Circular surface currents created by the interaction of the current and major land masses

 Density Currents ◦ Caused by differences in the temperature and salinity ◦ Cold water at the poles sinks and moves toward the equator ◦ May take 100 years for one density current to complete a cycle

Chapter 16: The Marine Environment BIG IDEA: The marine environment is geologically diverse and contains a wealth of natural resources.

16.1 SHORELINE FEATURES MAIN IDEA: The constant erosion of the shoreline and deposition of sediments by ocean waves creates a changing coastline.

16.1 Shoreline Features  Explain how shoreline features are formed and modified by marine processes Shore – area of land between water level at low tide and water level during intense storms Shore – area of land between water level at low tide and water level during intense storms Shaped by waves, tides, and currentsShaped by waves, tides, and currents Beach – area in which sediment is deposited Beach – area in which sediment is deposited Large sand grains – formed by large wavesLarge sand grains – formed by large waves Small sand grains – formed by small wavesSmall sand grains – formed by small waves

16.1 Shoreline Features  Describe the major erosional and depositional shoreline features. EROSIONAL FEATURES: EROSIONAL FEATURES: Wave-cut platform – flat erosional surface Wave-cut platform – flat erosional surface

16.1 Shoreline Features

 Long shore bar – submerged sandbar Long shore bar Long shore bar

16.1 Shoreline Features  Rip current – return water through gaps in the longshore bar out to sea

16.1 Shoreline Features  DEPOSITIONAL FEATURES

16.1 Shoreline Features  DEPOSITIONAL FEATURES Spit – narrow bank of sand that projects from a bend in the coastline Spit – narrow bank of sand that projects from a bend in the coastline Barrier island – long ridge of sand or sediment deposited or shaped by longshore current Barrier island – long ridge of sand or sediment deposited or shaped by longshore current Baymouth bar – forms when a spit closes off a bay Baymouth bar – forms when a spit closes off a bay Lagoons – shallow protected bodies of water behind baymouth bar or barrier island Lagoons – shallow protected bodies of water behind baymouth bar or barrier island Tombolo – connects island to mainland Tombolo – connects island to mainland

16.1 Shoreline Features  Identify protective structures used near shore. Sea wall - built in front of property, parallel to shore and worsens beach erosion Sea wall - built in front of property, parallel to shore and worsens beach erosion

16.1 Shoreline Features  Jetty – perpendicular to shoreline and trap sand

16.1 Shoreline Features  Jetty

16.1 Shoreline Features  Spiral Jetty

16.1 Shoreline Features  Breakwater – wall built parallel to shoreline but 100 – 500 yards into ocean, used to protect small boats

16.2 SEAFLOOR FEATURES MAIN IDEA: The ocean floor contains features similar to those on land and is covered with sediments of several origins.

16.2 Seafloor Features  Describe the major geologic features of the seafloor

16.2 Seafloor Features  Continental Shelf – shallow, gentle sloping area near coastlines  Continental Slope – steep, marks edge of continental crust  Continental Rise – sediments getting piled up from turbidity currents  Abyssal Plain – flattest part of ocean floor, 5- 6km below sea level  Mid-Ocean Ridge – underwater mountain range  Seamount – submerged basaltic volcanoes

16.2 Seafloor Features

Awesome Pictures!