| A | B |
|---|
| SONAR | A system that determines the distance of an object under water by recording echoes of sound waves; gets its name from Sound Navigation and Ranging. |
| CONTINENTAL SHELF | A gently sloping, shallow area of the ocean floor that extends outward from the edge of the continent. |
| CONTINENTAL SLOPE | An incline leading down from the edge of the continental shelf. |
| SEAMOUNT | A mountain on the ocean floor that is completely underwater. |
| ABYSSAL PLAIN | A smooth, nearly flat region of the deep ocean floor. |
| MID-OCEAN RIDGE | The undersea mountain chain where new ocean floor is produced; a divergent plate boundary. |
| TRENCH | A deep canyon on the ocean floor. |
| PLANKTON | Tiny algae and animals that float in water and are carried by waves and currents. |
| NEKTON | Free-swimming animals that can move throughout the water column. |
| BENTHOS | Organisms that live on the bottom of the ocean or another body of water. |
| FOOD WEB | The pattern of overlapping food chains in a habitat or ecosystem. |
| INTERTIDAL ZONE | The area that stretches from the highest high-tide line on land out to the point on the continental shelf exposed by the lowest low tide. |
| ESTUARY | A coastal inlet or bay where fresh water mixes with salty ocean water. |
| BRACKISH | Water that is partly salty and partly fresh, characteristic of estuaries. |
| NERITIC ZONE | The region of shallow water in the ocean that extends from the low-tide line out to the edge of the continental shelf. |
| OPEN-OCEAN ZONE | The area of the ocean beyond the edge of the continental shelf. |
| HOLDFAST | A bundle of rootlike strands that attaches algae to the rocks. |
| ATOLL | A ring-shaped coral island found far from land. |
| BIOLUMINESCENCE | The production of light by living things. |
| HYDROTHERMAL VENT | An area where ocean water sinks through cracks in the ocean floor, is heated by the underlying magma, and rises again through the cracks. |
| AQUACULTURE | The farming of saltwater and freshwater organisms. |
| NODULES | A black, potato-shaped lump formed when metals build up around pieces of shell on the ocean floor. |
| wave | the movement of energy through a body of water |
| wave height | the vertical distance between crest and trough |
| frequency | the number of waves that pass a point in a given time |
| longshore drift | the movement of sand along the shore |
| neap tide | a tide with the least difference betwwen high and low tides |
| rip current | a rush of water thar flows rapidly back to sea from the shore |
| groin | a wall that is used to slow beach erosion |
| tide | the daily rise and fall of the earth's water along coastlines |
| spring tide | twice a month the greatest distance between high and low tides |
| tsunami | a giant wave usually caused by an earthquake |
| salinity | the total amount of disolved salts in a sample of water |
| submersible | an underwater vehicle that resists ocean pressure |
| current | a stream of moving water that flows through the ocean |
| climate | the pattern of temp. and precipitation over a long period of time for a given area. |
| El nino | an unusual climate event that changes weather patterns and prevents upwelling |
| upwelling | the movement of cold water towards the shore that brings nutrients to sea life. |
| sonar | Sound Navigation And Ranging |
| continental shelf | Begins at the shore and reaches to the edge of the continental slope |
| continental slope | the steep edge of the continental shelf that drastically drops to the bottom of the ocean floor |
| abyssal plain | the long flat bottom of the deep ocean floor |
| mid-ocean ridge | a continuous range of underwater mountains that surrounds the earth. |
| divergent boundaries | where plates spread apart |
| convergent boundaries | where plates come together |
| trench | the deepest part of the ocean found at a convergent boundary |
| seafloor spreading | where plates spread apart at divergent boundaries |
| neritic zone | the zone from low tide to the edge of the continental shelf |
| open-ocean zone | beyond the edge of the continental shelf |
| Plankton | tiny plants and animals that float |
| nekton | free swiiming animals |
| benthos | animals that live on the ocean floor |
| food web | the feeding relationships that exist in a habitat |
| intertidal zone | the zone between high and low tides |
| estuaries | coastal inlets or bays where river water and ocean water mix |
| atoll | a ring shaped reef |
| bioluminescence | light produced by living things |
| hydrothermal vent | hot water that rises from cracks in the deep ocean floor |
| aquaculture | the farming of organisms that live in water |
| wave length | the horizontal distance between crests |
