Oceans

Question 1

Percent of earth covered by oceans (area)

Answer 1

75%

Question 2

Volume of water on earth in oceans

Answer 2

97. 2% of all water on earth

8. 4 million liters available per person

Question 3

Salinity

Answer 3

?The proportion of dissolved salts to pure water, usually expressed in parts per thousand (%)

Question 4

Most comment salt in ocean

Answer 4

NaCl

Question 5

Why ocean now thought to be salty

Answer 5

?As rainwater passes through soil and percolates through rocks, it dissolves some of the minerals, a process called weathering. This is the water we drink, and of course, we cannot taste the salt because its concentration is too low. Eventually, this water with its small load of dissolved minerals or salts reaches a stream and flows into lakes and the ocean. The annual addition of dissolved salts by rivers is only a tiny fraction of the total salt in the ocean. The dissolved salts carried by all the world’s rivers would equal the salt in the ocean in about 200 to 300 million years.

Question 6

Why salinity varies from place to place

Answer 6

? Vertical motion in the ocean are due to density differences do you two different temperature horizontal difference at the surface due to wind direction

Question 7

Whether relative percent of salts varies

Answer 7

?Seawater is denser than both fresh water and pure water (density 1.0 kg/L at 4 °C (39 °F)) because the dissolved salts increase the mass by a larger proportion than the volume. The freezing point of seawater decreases as salt concentration increases. At typical salinity, it freezes at about −2 °C

Question 8

Factors affecting density of water

Answer 8

Temperature ( cold water is more dense than hot)

Question 9

Currents

Answer 9

?An ocean current is any more or less permanent or continuous, directed movement of ocean water that flows in one of the Earth’s oceans. The currents are generated from the forces acting upon the water like the earth’s rotation, the wind, the temperature and salinity differences and the gravitation of the moon.

Question 10

Gulf stream and resulting temperatures in North Europe

Answer 10

?

Question 11

Black smokers, Life at vents, where they get their energy

Answer 11

?Hydrothermal vents are often associated with undersea volcanoes. This is because the vents are created and sustained by the heat of volcanic activity at tectonic plate boundaries, found throughout the globe.

At these locations, seawater seeps through cracks in the seafloor and is heated by molten rock. This causes chemical reactions between the two, and the altered seawater becomes hydrothermal fluid. This hot fluid then jets back into the ocean, forming a hydrothermal vent.

Despite the seemingly harsh volcanic environment, these vents are actually home to a variety of life. Microbes, such as bacteria and archaea, live here – harvesting chemical energy from the hydrothermal fluid. These microbes form the base of a unique foodchain that includes tubeworms, shrimp, and even crabs that live in communities around the vents.

Question 12

Sonar, how it works

Answer 12

Sonar (originally an acronym for SOund Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Two types of technology share the name “sonar”: passive sonar is essentially listening for the sound made by vessels; active sonar is emitting pulses of sounds and listening for echoes.

Question 13

Structures on Seafloor

Answer 13

?Part of the Earth’s outer surface that is comprised of the ocean floor, mid-oceanic ridges, continental rise, and continental slope. The ocean basins are filled with saline water that makes up the oceans. Flat plain found at the bottom of the ocean. The ocean floor represents the surface of the oceanic crust.

Question 14

Trenches

Answer 14

?a long, narrow, deep depression in the ocean floor, typically one running parallel to a plate boundary and marking a subduction zone.
plural noun: ocean trenches

Question 15

Mid ocean ridges

Answer 15

? A mid-ocean ridge or mid-oceanic ridge is an underwater mountain range, formed by plate tectonics. This uplifting of the ocean floor occurs when convection currents rise in the mantle beneath the oceanic crust and create magma where two tectonic plates meet at a divergent boundary.

Question 16

Seamounts

Answer 16

?A seamount is a mountain rising from the ocean seafloor that does not reach to the water’s surface (sea level), and thus is not an island. Seamounts are typically formed from extinct volcanoes that rise abruptly and are usually found rising from the seafloor to 1,000–4,000 m (3,300–13,100 ft) in height.

Question 17

Volcanic islands

Answer 17

?In geology, a high island or volcanic island is an island of volcanic origin. The term can be used to distinguish such islands from low islands, which are formed from sedimentation or the uplifting of coral

Question 18

Continental shelf

Answer 18

?the area of seabed around a large landmass where the sea is relatively shallow compared with the open ocean. The continental shelf is geologically part of the continental crust.

Question 19

Continental slope

Answer 19

?the slope between the outer edge of the continental shelf and the deep ocean floor

Question 20

Continental rise

Answer 20

?Continental rise definition, the gently sloping transition between the continental slope and the deep ocean floor, usually characterized by …

Question 21

Abyssal plain

Answer 21

?An abyssal plain is an underwater plain on the deep ocean floor, usually found at depths between 3,000 metres (9,800 ft) and 6,000 metres (20,000 ft). Lying generally between the foot of a continental rise and a mid-ocean ridge, abyssal plains cover more than 50% of the Earth’s surface.

Question 22

Characteristics of tides

Answer 22

?Tides are single waves that stretch across ocean basins. They are also shallow-water waves because their wavelengths greatly exceed the depth of the ocean. They occur due to complex interactions of the moon and sun.

Question 23

Causes of tides

Answer 23

Tides are caused by gravitational attraction of moon on oceans, creating bulges of water facing the moon and on the opposite side – earth rotate through the bulges and therefore has two high tides and two low tides at any given coastal location each day. Much more slowly, (30 days )the moon revolves around the earth and therefore the bulges only slowly change as they continue to be aligned with the moons position

Question 24

Types of tides

Answer 24

?The result is a smaller difference between high and low tides and is known as a neap tide. Neap tides are especially weak tides. They occur when the gravitational forces of the Moon and the Sun are perpendicular to one another (with respect to the Earth). Neap tides occur during quarter moons.

Question 25

Problems with oceans now

Answer 25

? Oceans turning acidic: carbon dioxide plus seawater equals weak carbonic acid.tons of released drugs by drug companies into waterways get in the oceans, is ultimate garbage can 950 pieces of trash found on uninhabited South Pacific 3000 miles from any other island. Overfishing, low oxygen zones growing(hypoxia)

Question 26

Role of ocean in carbon/oxygen cycle

Answer 26

?Oceans and the carbon cycle. The oceans influence the climate by absorbing and storing carbon dioxide. Climate change is caused by the accumulation of man-made carbon dioxide (CO2) and other greenhouse gases in the atmosphere.