S. 20 General Oceans Content

Practice flashcards for the Oceans General exam based on lecture notes.

What percentage of Earth’s surface is covered by oceans?

71%.

What percentage of Earth’s water is found in the oceans?

97%.

The Pacific Ocean is approximately how wide?

13,000 km.

Ocean bottom water is typically near what temperature?

Average ocean salinity is approximately:

3.5%.

Which process decreases salinity?

River discharge.

Which process increases salinity?

Evaporation.

What drives surface ocean currents?

Wind.

What drives deep ocean currents?

Temperature and salinity differences.

The Coriolis effect causes moving water in the Northern Hemisphere to curve:

Right.

Areas of circulating ocean water are called:

Gyres.

Oceanic garbage patches accumulate because:

Gyres trap floating debris.

How long does it take for water to complete the global conveyor belt?

~1000 years.

North Atlantic Deep Water forms because water becomes:

Colder and saltier.

Deep ocean currents are difficult to measure directly and are instead observed using:

Salinity data.

The Antarctic deep current acts as a:

Mixmaster redistributing cold salty water.

Oceans transport approximately what fraction of the heat needed to maintain Earth’s climate?

25%.

The Gulf Stream keeps which region warm?

Northern Europe.

If polar sea ice melts and freshens the North Atlantic, deep ocean circulation may:

Slow or stop.

A shutdown of deep ocean circulation is called:

Thermohaline collapse.

What percentage of atmospheric CO2 is taken up by the ocean?

25%.

Upwelling occurs when:

Offshore winds push deep water upward.

El Niño involves:

Tilting of the thermocline and warming in the eastern Pacific.

La Niña typically causes the SE and SW U.S. to have:

Wet summers.

Most open oceans have a depth of approximately:

4,000 m.

Below 500 m, ocean temperature is typically:

~4°C.

Shallow currents move fast because they are driven by:

Wind.

Deep currents move slowly because they are driven by:

Temperature and salinity gradients.

If Arctic sea ice melts, Europe would:

Warm significantly.

El Niño and La Niña redistribute warm and cold water globally, affecting:

Weather and climate over yearly cycles.