Oceanography: The Layers of the Ocean

Directions for Notes: Cut out all 5 pieces along lines. Put pieces together like a puzzle (see picture if needed). Glue or tape to notes. Directions for Notes:

5 Zones of the Ocean https://www.youtube.com/watch?v=gRjGs7vAmlE

Epipelagic Zone Also called the sunlight zone Depth: surface to 660 feet Temperature: 97oF (36oC) in the Persian Gulf to 28oF (-2oC) near the north pole Light: most of the visible light exists

Algae that live in the epipelagic zone are responsible for much of the original food production for the entire ocean and create at least 50% of the oxygen in the atmosphere (both through photosynthesis).  Organisms that live in the epipelagic zone may come into contact with the sea surface. Interaction with the wind keeps this layer mixed and thus allows the heating from the sun to be distributed vertically. At the base of this mixing layer is the beginning of the thermocline. Epipelagic zone

Mesopelagic Zone Sometimes called the twilight zone Depth: 660 feet - 3,000 feet Temperature: has the most fluctuation in temperature Light: lack of (bioluminescence begins to appear on life) Contains thermocline

Thermocline Region where water temperature decreases rapidly with increasing depth and transition layer between the mixed layer at the surface and deeper water https://youtu.be/PP42k7YD-nw

Because of the lack of light, it is within this zone that bioluminescence begins to appear on life. The eyes on the fishes are larger and generally upward directed, most likely to see silhouettes of other animals (for food) against the dim light. The mesopelagic zone is much larger than the epipelagic, and the most numerous vertebrates on Earth (small bristlemouth fishes) live in this zone.  Many of the species of fishes and invertebrates that live here migrate up into shallower, epipelagic depths to feed, but only under the cover of night. Scientists up until the mid- 20th century did not believe animals could survive at these depths because of the pressure. Today we know some animals thrive in these conditions and whales can dive from the surface deep into the ocean where their prey on colossal squid that live in these pressures. Mesopelagic zone

Bathypelagic Zone Also called the midnight zone Depth: 3,300 – 13,100 feet Temperature: constant temperature about 39oF (4oC) Light: constant darkness Pressure: reach over 5850 pounds per square inch https://www.youtube.com/watch?v=0B0EhuxJsts

In the 1970s a research vessel discovered black smokers where a community of animals were thriving including giant tubeworms. They do not require sunlight to live but live on bacteria that grows around the thermal vents that create the black smokers. The pressure in the bathypelagic zone is extreme and at depths of 13,100 feet (4,000 meters), reaches over 5850 pounds per square inch! Yet, sperm whales can dive down to this level in search of food. The bathypelagic is much larger than the mesopelagic and 15 times the size of the epipelagic.  It is the largest ecosystem on earth.  The upper bound of this zone is defined by a complete lack of sunlight.  Organisms in the bathypelagic live in complete darkness, 24 hours per day.  The darkness can be interrupted, however, by some light caused by the organisms themselves.  This so called bioluminescence can be used to attract prey or to find a mate.  Some species have lost their ability to see anything at all. Bathypelagic zone

Abyssopelagic Zone Depth: 13,100 feet (4,000 meters) to 19,700 feet (6,000 meters) Temperature: constantly near freezing Light: pitch black ¾ of the area of the deep-ocean floor lies in this zone

The name (abyss) comes from a Greek word meaning "no bottom" because they thought the ocean was bottomless. Three-quarters of the area of the deep-ocean floor lies in this zone. This zone is characterized by a relative lack of life.  It truly is the abyss. Abyssopelagic zone

Hadalpelagic Zone Depth: 19,700 feet (6,000 meters) to the very bottom at 35,797 feet (10,911 meters) Temperature: constant at just above freezing Light: NO LIGHT

Even at the very bottom life exists Even at the very bottom life exists. In 2005, tiny single- celled organisms, called foraminifera, a type of plankton, were discovered in the Challenger Deep trench southwest of Guam in the Pacific Ocean. The deepest a fish have ever been found, Abyssobrotula galatheae, was in the Puerto Rico Trench at 8,372 meters (27,460 feet). Where deep, wide trenches occur in the otherwise flat seafloor, the open water that fills them is the hadopelagic zone.  By this definition, all of the deepest parts of the ocean conclude in the hadopelagic.  The deepest known ocean depth is nearly 11,000 m (36,000 feet or almost 7 miles). Hadalpelagic zone

http://www.livescience.co m/38174-how-to-explore- the-deep-sea.html http://nationalgeographic. org/media/ocean- exploration/ Exploring the ocean