1. Oceans, Waves and Tides
Marine Biome

2. Marine Biomes
Scientists divide the ocean into
zones HORIZONTALLY and
VERTICALLY.

3. Vertical Photoic, Aphotic, and Benthic zones (same as with lakes)
Aphotic zone of open ocean = desert of marine biome in terms of biomass; absence of sunlight limits diversity

4. Horizontal
Neritic Zone
Continental Shelf
Intertidal Zone
Oceanic Zone

5. Neritic Zone
Region between the continental shelf and the surface of the water = 8% of world ocean.
Ecosystems in this zone--reefs & estuaries
Here sunlight reaches the benthic zone of the continental shelf = photosynthesis
High in mineral nutrients
Location determined by location of continental shelf.

6. Continental Shelf Shallow border that surrounds the continents
Between the shore and about 500m below the surface of the water
Reefs are a natural structure built on a continental shelf
Estuary is region of water where a freshwater source, usually mouth of river, meets salt water of ocean. (brackish); estuary from Latin for tide

7. Swamps and Marshes
Compared to a temperate deciduous forest of same size, a swamp is twice as productive.
Sediment accumulation contribute to formation of salt marshes and mangrove forests
Mangrove swamp – shores of Florida

8. Reefs
Coral Reefs are made of calcium carbonate – skeletons of millions of tiny corals
Topsoil washes onto a coral reef making water cloudier limiting photosynthesis
Coral Reefs are very sensitive to pollution
Like rainforest-very productive & huge variety of organisms
One-third of all ocean fish live on or depend on coral reefs

9. Intertidal Zone
Alternates between periods of exposure and periods of submersion twice a day due to tides.
Specialized organisms
Salt Marshes & mangrove swamps also known as coastal wetlands developed by subsidence
--weight of accumulated sediments causing delta to sink under the water.
25% of world’s mangrove species found in USA

10. Oceanic Zone
Open Ocean – largest zone – making up more than 90% of the surface area of the world ocean.
Ranging from 500m along continental slopes to a depth of 11,000m
Detritus (dead organic materials) provide feed
Mainly aphotic zone (no sunlight)
Main producers of open oceans are phytoplankton (photic zone)
Benthic organisms – clams, worms, sponges

11. Ocean Currents Energy from sun – temperature, salinity and density
Increased radiation along equator make more saline seawater
Water in ocean flows in patterns called ocean currents

12. Wind-drive ocean surface currents
Wind driven surface currents
Wind-drive ocean surface currents
London = 51 deg N James Bay = 51 deg. N
Edinburgh = 55deg N, same latitude as Ontario’s Polar Bear Provincial Park
Total water in ocean surface circulation = about 100 Amazon Rivers (20 million m3/s). It requires years to complete cycle.
How fast? A few miles/hr (Gulf Stream off of Miami = 4.5 mph)
How much? Total water in ocean surface circulation = about 100 Amazon Rivers (20 million m3/s).

13. Waves
A Wave is a rhythmic movement that carries energy through matter or space.
In oceans, waves move through seawater

15. Waves Caused by: Wind Earthquakes
Gravitational force of the Moon and Sun.

16. Parts of a Wave Crest – highest point of a wave
Trough – lowest point of a wave
Wave Height – vertical distance between the crest and the trough
Wavelength – horizontal distance between two crests or two troughs

17. Wavelength
Crest
Wave Height
Still Water
Trough
Wave Parts

18. Wave Movement
When a wave passes through the ocean, individual water molecules move up and down but they do not move forward or backward.

20. Wave Movement
When a wave breaks against the shore, the crest outruns the trough and the crest collapses.
Called a breaker.
In this case, water does move forward and backward.

22. Waves Caused by Wind
When wind blows across a body of water, friction causes the water to move along with the wind.
Wave Height depends on –
Wind speed
Distance over which the wind blows
Length of time the wind blows

26. Tides The rise and fall in sea level is called a tide.
Caused by a giant wave.
One low-tide/high-tide cycle takes about 12 hrs and 25 min.
Tidal range is the difference in ocean level between high-tide and low-tide

27. What is the Tidal Range? HT = 30 ft, LT = 20 ft HT = 20 ft, LT = 12 ft

28. Gravitational Effect of the Moon
Two big bulges of water form on the Earth:
one directly under the moon
another on the exact opposite side
As the Earth spins, the bulges follow the moon.

30. Gravitational Effect of the Sun
Spring Tides
Earth, Moon, and Sun are lined up
High Tides are higher and Low Tides are lower than normal

32. Gravitational Effect of the Sun
Neap Tides
Earth, Moon, and Sun form right angles
High Tides are lower and Low Tides are higher than normal

34. The End