Download Ocean resources and oceanography-Unit C Chapter 3

Ocean Resources and Oceanography
• What is the most important gas in the water
for ocean organisms?
• OXYGEN!
Ocean Animals
• All ocean animals use cellular respiration in
water
• Oxygen + Sugar (from food) = Carbon Dioxide
+ Water + Energy
How does dissolved oxygen get into
the water?
• Most oxygen in water comes from algae
(seaweed) and microscopic aquatic plants
called phytoplankton
• They get oxygen into the water through
photosynthesis
• Additional oxygen is added to the ocean
through streams, rivers, and rain
Phytoplankton off the coast of South
America
Show phytoplankton video
Question:
• Why are phytoplankton so important to ocean
waters since they are a very small plant?
• How could they be a bio-indicator of ocean
health?
Carbon Dioxide
• carbon dioxide is also located in the
water
• Why is CO2 important?
• Main ingredient in carbon for sea shells
• Phytoplankton need it to start
photosynthesis
Where does CO2 come from?
•Animals breathing it out
in water
•Absorbed into the ocean
from the air
Salinity
• The amount of dissolved salt in the oceans
• What kinds of things affect the salinity of
water?
• Increase in temp will cause water to evaporate leaving
behind more salt
• Increase in water will cause water to become more
diluted and decrease the density of water
What kind of things affect the salinity
of water?
• Evaporation = more salinity because less water
• Precipitation = less salinity because more
water
Upwelling
• Cool dense water from bottom that has lots of
oxygen and nutrients will move to the top of
the ocean
• Why important?
• food and oxygen for fish and other animals
that live closer to the top
• Occurs near the continental shelf
Upwelling
Where do we find the most fish in the
oceans?
• Near areas of upwelling!
Downwelling
• Downwelling-oxygen rich cool dense water
falling down to the bottom of the ocean,
• Why is downwelling important?
• Cool dense oxygenated water to the bottom
for fish.
Downwelling
Review:
• What is the difference between upwelling and
downwelling?
• Why is upwelling so important to ocean life at
or near the surface?
• Why is downwelling important for fish near
the bottom of the ocean?
Kelp- type of
seaweed
that grows
in vast
underwater
forests
Kelp Forest
Play kelp forest video
Questions:
• What is the importance of a kelp forest?
• How could they be a type of bio-indicator?
Ocean resources used by people
•
•
•
•
3 Largest uses
Food
Desalination of ocean water for fresh water
Salt
Desalination
• Desalination is used to separate salt from the
seawater
• 1. Boil the water
• 2. Capture the vapor and cool it
Question?
• How could desalination help water shortages
in some countries?
• Why do you think we do not use it that much
on our planet?
Ocean Food
• 75 million tons of food taken-more than
anywhere else
• Examples:
– Shrimp, oysters, crabs, mussels, and lobster
– Seaweed such as kelp is also used
• Used in ice cream and jellies to thicken them
• Seaweed is also a source of food for many countries
Dangers of overfishing
• What is overfishing?
• Capturing fish faster and in larger quantities
than the fish can reproduce
Play overfishing video
Questions?
• Why is overfishing a problem?
• How could we do to slow down overfishing,
but still have fish to eat?
Oceanography
• What is oceanography?
• Study of the physical properties of the oceans
• Study density, salinity, temperature, and pH
Deep ocean technology
• Sonar
• Used to map the surface of the ocean floor
• Sound navigation and ranging
• Method is used by sending sound waves to
the bottom of the ocean that are then
bounced back.
SONAR
• Longer it takes for a sound wave to return, the
deeper the depth
Benefits of sonar
• Map the ocean floor
• Locate underwater mountains, canyons, and
trenches
• Help to understand and track tectonic plate
movement
• Locate fish
Question
• What are two benefits of sonar?
Underwater vessels
• Remotely Operated Vessels (ROV’s)
• Controlled by someone on a ship
Piloted Vessels
• Small vessels piloted by humans to explore
the ocean
Remotely Operated
Vehicles
Play undersea rover video
Question?
• What does ROV stand for?
• Why do we use ROV’s?
ALVIN
• 1st extreme deepwater submarine piloted by
humans
• Carries up to 3 people
• Reach 3 miles underwater
• Built in 1964
Alvin
Ocean Currents
• How are ocean currents created?
• Ocean currents are created by different
densities of water caused by temperature.
• Why are currents important?
• Move nutrients around for fish
• Fish and whales use them to increase their
migratory patterns
Surface Currents
• Currents of water at or near the surface (100200 ft) that follow certain patterns
Surface Currents Affect Climate
• Warm surface currents near the northern
latitude causes some places to experience
warm temperatures
• Great Britain and Canada are at the same
latitude.
• Do they share the same weather?
• NO! Canada is much colder and receives a lot
more snow than Great Britain.
• WHY?
Canada vs. Great Britain
• The western part of Canada is affected by very
cold waters coming from the Arctic Ocean
• Causes
– Lots of snow and allows distinct animals like polar
bears and walruses to survive
• Great Britain is affected by warm water
coming from the Gulf of Mexico.
• Causes
– Very little snow but a ton of rain and mild winters.
Waves
• Motion across the top of water (wind) causes
waves
• What is cohesion?
• Water sticking to water
• Transfers energy throughout water and each
wave passes the energy onto the next one.
Tides
• Tides-extreme change in water levels because
of the moons gravitational pull
• What is cohesion?
• Water sticking to water
• How are cohesion and the gravitational pull of
the moon related?
• The water molecules sticking together allows
the water to move as one.
Class discussion
• What are three resources obtained from
oceans?
•
•
•
•
Which of these processes is
responsible for increasing dissolved
oxygen levels in the oceans?
A. Respiration
B. Photosynthesis
C. Topography
D. Harvesting Kelp
Which of these is added to the ocean
as a result of respiration?
•
•
•
•
A.
B.
C.
D.
Oxygen
Dissolved nutrients
Minerals
Carbon dioxide
Scientists on a ship are using sonar to map the
ocean floor. They send out a pulse at Point A
that takes 4 seconds to return to the ship. At
Point B, the sound pulse takes 8 seconds to
return to the ship. What conclusion can you
make?
A. They are the same depth
B. Water at Point A is twice as deep as that at Point
B
C. Water at Point B is twice as deep as that at Point
A
D. Water at Point B is half as deep as that at Point A