Chapter 13 Section 3 Life in the Ocean
Chapter 13 Exploring the Oceans
Preview
Section 1
Section 2
Section 3
Section 4
Section 5
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Chapter 13 Section 1 Earth’s Oceans
Bellringer
Look at a photo of Earth taken from space. Predict the percentage of Earth’s surface that is covered by water.
Write your prediction in your science journal.
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Chapter 13 Section 1 Earth’s Oceans
Objectives
• List the major divisions of the global ocean.
• Describe the history of Earth’s oceans.
• Identify the properties of ocean water.
• Describe the interactions between the ocean and the atmosphere.
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Chapter 13 Section 1 Earth’s Oceans
Divisions of the Global Ocean
• The largest ocean is the Pacific Ocean.
• The other oceans, listed from largest to smallest, are:
• the Atlantic Ocean
• the Indian Ocean
• the Arctic Ocean
• the Southern Ocean
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Chapter 13 Section 1 Earth’s Oceans
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Chapter 13 Section 1 Earth’s Oceans
How Did the Oceans Form?
• About 4.5 billion years ago, there were no oceans.
• Sometime before 4 billion years ago, water vapor in the atmosphere condensed and fell as rain.
• The rain filled the deeper levels of Earth’s surface and the first oceans began to form.
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Chapter 13 Section 1 Earth’s Oceans
How Did the Oceans Form?, continued
• The shape of the oceans has changed over time.
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Chapter 13 Section 1 Earth’s Oceans
Characteristics of Ocean Water
• Dissolved Gases Nitrogen, oxygen, and carbon dioxide are the main gases dissolved in ocean water.
• Solids Sodium chloride, or table salt, is the most abundant dissolved solid in the ocean. Other solids are also found in ocean water.
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Chapter 13 Section 1 Earth’s Oceans
Characteristics of Ocean Water, continued
• Salinity is a measure of the amount of dissolved solids in a given amount of liquid.
• Changes in Salinity Climate and water movement affect salinity. Costal water in cool, humid places has a low salinity. Slow-moving bodies of water have higher salinity than other parts of the ocean do.
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Chapter 13 Section 1 Earth’s Oceans
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Chapter 13 Section 1 Earth’s Oceans
Characteristics of Ocean Water, continued
• Temperature Zones The temperature of ocean water decreases as depth increases.
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Chapter 13 Section 1 Earth’s Oceans
Characteristics of Ocean Water, continued
• Surface Temperature Changes Surface-zone temperatures vary with latitude and the time of year.
• Surface temperatures range from 1ºC near the poles to about 24 ºC near the equator.
• The surface zone is heated more in the summer.
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Chapter 13 Section 1 Earth’s Oceans
The Ocean and the Water Cycle
• The water cycle is the continuous movement of water from the ocean to the atmosphere to the land and back to the ocean.
• The ocean is an important part of the water cycle because nearly all of Earth’s water is in the ocean.
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Chapter 13 Section 1 Earth’s Oceans
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Chapter 13 Section 1 Earth’s Oceans
A Global Thermostat
• The ocean regulates atmospheric temperatures.
• A Thermal Exchange The ocean absorbs and releases thermal energy much more slowly than dry land does.
• The circulation of warm water causes some coastal lands to have warmer climates than they would have with the currents.
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Chapter 13 Section 2 The Ocean Floor
Bellringer
Pretend you have walked off the edge of North
America and into the depths of the Atlantic Ocean.
As you walk along the ocean floor toward Europe, what do you see? Draw the ocean floor as you imagined it.
Illustrate your answer in your science journal.
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Chapter 13 Section 2 The Ocean Floor
Objectives
• Describe technologies for studying the ocean floor.
• Identify the two major regions of the ocean floor.
• Classify subdivisions and features of the two major regions of the ocean floor.
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Chapter 13 Section 2 The Ocean Floor
Studying the Ocean Floor
• Seeing by Sonar Scientists use sonar to determine the ocean’s depth.
• Oceanography via Satellite Scientists use images from the satellite Seasat to study ocean currents.
• Studying the Ocean with Geosat Scientists use the Geosat satellite to measure slight changes in the height of the ocean’s surface.
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Chapter 13 Section 2 The Ocean Floor
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Chapter 13
Section 2 The Ocean Floor
Revealing the Ocean Floor
• Regions of the Ocean Floor The two regions of the ocean floor are the continental margin and the deep-ocean basin.
• Underwater Real Estate The continental margin and the deep-ocean basin are subdivided into different areas and have different features, as shown on the next two slides.
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Chapter 13
Section 2 The Ocean Floor
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Chapter 13
Section 2 The Ocean Floor
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Chapter 13
Section 2 The Ocean Floor
Exploring the Ocean with Underwater
Vessels
• Piloted Vessels: Alvin and Deep Flight Alvin and
Deep Flight are two research vessels that can reach some of the deepest parts of the ocean.
• Robotic Vessels: JASON II and Medea JASON II and Medea are a robotic team. JASON II explores the ocean floor. Medea is attached to JASON II with a tether and explores above the the sea floor.
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Chapter 13
Section 3 Life in the Ocean
Bellringer
Imagine you are a marine biologist who must classify marine life into three groups. What criteria would you use in your classification system?
Record your response in your science journal.
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Chapter 13
Section 3 Life in the Ocean
Objectives
• Identify the three groups of marine life.
• Describe the two main ocean environments.
• Identify the ecological zones of the benthic and pelagic environments.
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Chapter 13 Section 3 Life in the Ocean
Three Groups of Marine Life
• Organisms that float or drift freely near the ocean’s surface are called plankton.
• Organisms that swim actively in the open ocean are called nekton.
• Organisms that live on or in the ocean floor are called benthos.
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Chapter 13 Section 3 Life in the Ocean
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Chapter 13 Section 3 Life in the Ocean
The Benthic Environment
• The Benthic Environment is the region near the bottom of a pond, lake, or ocean.
• The benthic environment is divided into ecological zones based on where different types of benthos live.
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Chapter 13 Section 3 Life in the Ocean
The Benthic Environment, continued
• The Intertidal Zone is where the ocean meets the land.
• The intertidal zone is exposed to air for part of the day. Organisms found in this zone include starfish, sea anemones, barnacles, crabs, and seaweed.
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Chapter 13 Section 3 Life in the Ocean
The Benthic Environment, continued
• The Sublittoral Zone The sublittoral zone begins at the low-tide limit and extends to the continental shelf, which is about 200 m below sea level.
• The temperature, water pressure, and amount of sunlight remain fairly constant in this zone. Coral is found in this zone.
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Chapter 13 Section 3 Life in the Ocean
The Benthic Environment, continued
• The Bathyal Zone The bathyal zone extends from the continental shelf to the abyssal zone. The depth of this zone ranges from 200 m to 4,000 m below sea level.
• Because of the lack of sunlight, few plants are found in this zone. Animals such as sea stars, sponges, and octopuses are found here.
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Chapter 13 Section 3 Life in the Ocean
The Benthic Environment, continued
• The Abyssal Zone The abyssal zone is the largest ecological zone of the ocean and can reach
4,000 m in depth.
• No plants live in this zone. The few animals that can be found include crabs, sponges, sea cucumbers, and worms.
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Chapter 13 Section 3 Life in the Ocean
The Benthic Environment, continued
• The Hadal Zone The hadal zone consists of the floor of the ocean trenches and any organisms found there. The depth can reach from 6,000 m to
7,000 m below sea level.
• The only organisms that have been found in this zone include a type of sponge, a few species of worms, and a type of clam.
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Chapter 13 Section 3 Life in the Ocean
The Pelagic Environment
• The zone near the ocean’s surface and at the middle depths is called the pelagic environment.
• The pelagic environment is above the abyssal zone and beyond the littoral zone.
• The two major zones of the pelagic environment are the neritic zone and the oceanic zone.
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Chapter 13 Section 3 Life in the Ocean
The Pelagic Environment, continued
• The Neritic Zone The neritic zone is a warm, shallow zone that covers the continental shelf.
• The neritic zone contains the largest concentration of marine life.
• The neritic zone receives more sunlight than other ocean zones, allowing plankton to grow and serve as a food supply.
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Chapter 13 Section 3 Life in the Ocean
The Pelagic Environment, continued
• The Oceanic Zone The oceanic zone includes the volume of water that covers the entire sea floor except for the continental shelf.
• The deeper parts of the oceanic zone have colder water temperatures and much greater pressure than the neritic zone.
• Organisms are more spread out in the oceanic zone.
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Chapter 13 Section 4 Resources from the Ocean
Bellringer
Tabitha drove her car to the market to buy a tuna steak for dinner. When she got home, she poured herself a glass of water, fired up her gas grill, and cooked the tuna. Identify four of Tabitha’s items or activities that involve resources obtained from the sea.
Record your response in your science journal.
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Chapter 13 Section 4 Resources from the Ocean
Objectives
• List two ways of harvesting the ocean’s living resources.
• Identify three nonliving resources in the ocean.
• Describe the ocean’s energy resources.
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Chapter 13 Section 4 Resources from the Ocean
Living Resources
• Fishing the Ocean Fish are the larges group of organisms take from the ocean.
• Farming the Ocean People have begun to raise ocean fish and other organisms in fish farms to help meet the demand for seafood.
• Savory Seaweed Many types of seaweed are harvested from the ocean for use as food.
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Chapter 13 Section 4 Resources from the Ocean
Nonliving Resources
• Oil and Natural Gas Oil and natural gas are used for energy and are found under layers of impermeable rock.
• Searching for Oil Scientists use seismic equipment to find oil and natural gas under the ocean floor.
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Chapter 13 Section 4 Resources from the Ocean
Nonliving Resources, continued
• Fresh Water and Desalination Fresh water can be collected for human use by removing the salt from ocean water.
• Sea-Floor Minerals Scientists estimate that 15% of the ocean floor is covered with mineral-rich nodules.
However, mining them is costly and difficult.
• Tidal Energy is energy generated from the movement of the tides.
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Chapter 13 Section 4 Resources from the Ocean
Tidal Energy
Click below to watch the Visual Concept.
Visual Concept
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Chapter 13 Section 4 Resources from the Ocean
Nonliving Resources, continued
• Wave Energy The constant motion of waves is a clean, renewable energy resource.
• Researchers have found certain areas of the world where wave energy can generate enough electrical energy to make building power plants worthwhile.
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Chapter 13 Section 5 Ocean Pollution
Bellringer
How does ocean pollution affect your life? What are possible ways you contribute to ocean pollution in your daily life?
Write your answers in your science journal.
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Chapter 13 Section 5 Ocean Pollution
Objectives
• Explain the difference between point-source and nonpoint-source pollution
• Identify three different types of point-source pollution.
• Describe what is being done to control ocean pollution.
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Chapter 13 Section 5 Ocean Pollution
Nonpoint-Source Pollution
• Pollution that comes from many sources rather than from a single site is called nonpoint-source pollution.
• Most ocean pollution is nonpoint-source pollution and can be difficult to regulate and control.
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Chapter 13 Section 5 Ocean Pollution
Point-Source Pollution
• Trash Dumping Dumping trash in the deeper parts of the ocean is a common practice in many countries.
• Effects of Trash Dumping Trash thrown in the ocean can be harmful to ocean organisms.
• Sludge Dumping Sludge is the solid waste removed from raw sewage. Sludge can pollute beaches and kill marine life.
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Chapter 13 Section 5 Ocean Pollution
Point-Source Pollution, continued
• Oil Spills If not handled properly, oil transports can cause oil spills.
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Chapter 13 Section 5 Ocean Pollution
Point-Source Pollution, continued
• Effects of Oil Spills Oil spills can harm or kill many plants and animals.
• Preventing Oil Spills New technology is being used to safeguard against oil spills. Oil tankers are now being built with two hulls instead of one.
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Chapter 13 Section 5 Ocean Pollution
Saving Our Ocean Resources
• Nations Take Notice Many international agreements and laws restrict ocean pollution.
• Citizens Taking Charge People have demanded that their governments work to solve ocean pollution and have begun organizing beach cleanups.
• Action in the United States The U.S. has passed laws to control local pollution.
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Chapter 13 Exploring the Oceans
Concept Mapping
Use the terms below to complete the concept map on the next slide. ecological zones benthos intertidal zone benthic zone nentic zone marine life oceans plankton oceanic zone
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Chapter 13 Exploring the Oceans
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Chapter 13
Exploring the Oceans
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