Oceanology Unit 3 Test Prep

What causes variations in solar radiation on earth?

The daytime-nightime cycle and seasonal cycle.

Extra info: Low-latitude regions receive more solar radiation than high-latitude regions, but oceanic and atmospheric circulation transfer heat around the globe.

What is the atmosphere composed of?

78 percent nitrogen, 21 percent oxygen, 0.9 percent argon, and 0.1 percent other gases.

How do temperature and pressure change with elevation in troposphere?

Temperature decreases with altitude, and pressure decreases as well.

What factors influence the density of air?

its temperature, its pressure, and how much water vapor is in the air.

What causes wind?

Pressure differences in the atmosphere.

Extra info: Air always moves from high pressure to low pressure, so air travels from the high pressure at the poles toward the low pressure at the equator. Thus, there are strong northerly winds in the Northern Hemisphere and strong southerly winds in the Southern Hemisphere.

The atmosphere is heated from below; its changing temperature, density, water vapor content, and pressure cause atmospheric movement, which is called wind.

What is an atmospheric convection cell and how does air move within it?

the movement of air in a circular motion. Warm, less dense air rises and cold, more dense air sinks.

What is the Coriolis Effect?

Because the Earth rotates on its axis, circulating air is deflected toward the right in the Northern Hemisphere and toward the left in the Southern Hemisphere and Equator.

What is the role of atmospheric circulation in establishing pressure gradients, heat transfer, and climate patterns?

Atmospheric circulation is the cause of convection cells, which affect pressure, heat, and climate.

More specifically, the cells cause the movement of heat (so literally heat transfer). Depending air causes high pressure and rising air causes low pressure. These different pressures cause different weather (dry, clear, fair conditions in high pressure and cloudy conditions with lots of precipitation in low pressure areas.)

How do weather & precipitation alternate with latitude?

At very high and very low latitudes, there is little daily and minor seasonal change in weather. Equatorial regions are usually warm, damp, and typically calm.

How does wind movement vary with latitude?

regions near the equator are characterized by low winds, while mid-latitudes experience much faster airflow.

Which way do winds move around high/low pressure systems in the Northern Hemisphere?

clockwise around areas of high pressure and counterclockwise around areas of low pressure.

What is the difference between a land breeze and a sea breeze?

Land breezes come from the land and go towards the sea, while sea breezes come form the sea and blow towards the land. Land breezes occur during night and the land is cool, causing warmer denser air to flow towards the sea, and a sea breeze is during the day when the land is warmed by the sun and is replaced with a cool breeze.

What is the average albedo of Earth's surface?

30%

What is a warm front?

The contact between a warm air mass moving into an area occupied by cold air.

What is a cold front?

The contact between a cold air mass moving into an area occupied by warm air

What physical property of air allows some parcels to rise and others to sink?

Density

The movement of air from a high-pressure area to a low-pressure area is referred to as what?

Wind

During the course of a sunny day a __________-pressure region sets up over land and a ___________-pressure region sets up over the ocean.
TERMENGLISH

low; high

Which oceanic climate region is characterized by strong westerly winds and periodic strong storms?

temperate

What causes Earth's seasons?

the tilt of the axis

Why is air with significant amounts of water vapor less dense than dry air?

Water vapor has less mass than the constituents of dry air.

Increases in atmospheric and oceanic warming worldwide will most likely result in an increase in which ice structures?

icebergs

The Coriolis effect is a result of what?

Earth spinning on its axis

What is the major gas contributing to dry air?

Nitrogen

Why are the polar regions usually high atmospheric pressure zones?

Cold air descends in the areas.

Why is sunlight more concentrated at the equator compared to the polar regions?

The sun comes in at a high angle at the equator compared to a low angle at the poles.

Due to Coriolis, objects in the Northern Hemisphere are deflected to the ______, and objects in the Southern Hemisphere are deflected to the________.

right; left

As latitude increases, the effect of Coriolis __________.

increases

In which layer of the atmosphere do temperatures decrease with increasing altitude?

troposphere

What is a current?

Masses of ocean water that flow from one place to another.

What are the types of currents and what are their respective causes?

Surface currents - caused by wind
Deep currents - caused when dense water sinks and spreads slowly beneath the surface (so by density)

What is Ekman transport and how is it related to the Coriolis Effect?

Wind blows onto water, and because of that it moves. When moving, each layer of the water moves at different speeds and angles due to the coriolis effect.

Where is the effect of the wind on the water the greatest?

The surface.

How does the direction of net water transport relate to the wind direction?

right of the wind direction in the Northern Hemisphere and to the left of the wind direction in the Southern Hemisphere

How does the deflection of surface currents vary between the Northern and Southern Hemisphere?

45 degrees right in the north and left in the south.

What is a gyre and what factors contribute to their formation?

A large circling loop of water. Global wind patterns, Earth's rotation, and Earth's landmasses contribute to their formation.

How do ocean currents impact coastal climates?

Warm ocean currents warm the nearby air. This warm air can hold a large amount of water vapor, which puts more moisture (high humidity) in the atmosphere. When this warm, moist air travels over a continent, it releases its water vapor in the form of precipitation.

Cold ocean currents cool the nearby air, which is more likely to have low water vapor content. When the cool, dry air travels over a continent, it results in very little precipitation.

How can shifts in seasonal winds affect upwelling/downwelling?

In winter, winds blow from the south to the north, resulting in downwelling. During the summer, winds blow from the north to the south, and water moves offshore, resulting in upwelling along the coast.

What variables would indicate the presence of upwelling on the Pacific Northwest Coast?

Nitrate and nutrients in upwelled waters and cold waters.

How do conditions vary between a Non-El Niño Year and an El Niño year? (Think about changes in winds, weather and water movement)

During normal conditions, upwelling brings water from the depths to the surface; this water is cold and nutrient rich. During El Niño, upwelling weakens or stops altogether. Therefore, there is little wing movement. It makes the South wetter and the North warmer and dryer. This can kill of many organisms and causes an economic disaster.

How does deep water circulation compare to surface water movement?

Deep water circulation is slower than surface water.

Where does water involved in deep ocean currents originate?

The surface. It is pulled down when it increases in density.

What is a La Niña?

The opposite of El Nino. It's a decrease in water temperature. It typically will follow an El Nino event.

When Coriolis effect and gravity are balanced in a subtropical convergence, what is the result?

geostrophic current

A reduction in atmospheric pressure differences across the Pacific Ocean results in what?

reduced wind across the basin

Why do subtropical gyres rotate in one direction and subpolar gyres rotate in the opposite direction?

Subtropical gyres are generated by the westerlies and trade winds, and subpolar gyres are generated by the polar easterlies.

What is the most dramatic impact of an El Niño on the west coast of South America?

lack of upwelling, therefore lots of death.

Why does upwelling increase biological productivity?

It provides nutrients used by phytoplankton.

Where on the globe does deep-water formation occur?

the polar regions

What is the most likely scenario if conveyer belt circulation shut down in the North Atlantic?

Polar temperatures would encroach south.

An Ekman spiral is a balance between what two factors?

Coriolis effect and friction

If the Gulf Stream were to turn right into the Atlantic Ocean near the coast of South Carolina, the climate of the northeast United States would become ____ and the climate of Europe would become ____.

cooler; warmer

The global ocean conveyer belt circulation is most responsible for distributing what?

heat

Which of the following is considered to be normal circulation in the Pacific Ocean?

Walker Circulation

What is an ecological benefit of downwelling?

export of dissolved oxygen to the deep ocean

A breakdown of normal circulation due to wind reduction in the Pacific Ocean results in what?

El Niño

What is the generating force that starts surface currents?

wind

Offshore winds most likely result in which of the following?

coastal upwelling

What is the driving force behind the generation of deep-water currents?

density differences

Why do areas along eastern boundary currents typically have cool, dry climates?

Eastern boundary currents are coming from the poles and contain colder water.

What are the major wind belts of the world?

The trade winds, the prevailing westerlies, and the polar easterlies. Horse latitudes and doldrums are also winds. (these may or may not be important, idk)

How do high- and low- pressure zones alternate with latitude?

0 is low, 30 is high, 60 is low, and polar is high.

(Numbers refer to the latitude, negative or positive)

As a wave approaches the shore, what happens to wave speed, height, and length, respectively?

decrease, increase, and decrease

Which two wave parameters are needed in order to calculate wave steepness?

wave height and wavelength

What is the generating force providing energy for the majority of waves in the ocean?

Wind

Which breaker type is the most exciting to go surfing?

plunging

Where does an internal wave occur?

water-water interface

When a wind wave is first generated, what is the wave type that develops?

capillary wave

The distance the wind blows in one direction without interruption is referred to as what?

wind fetch

Waves that have traveled out of their area of origin and have become uniform and symmetrical are known as ______.

Swells

Which of the following would be the most likely to create a tsunami?

vertical displacement at an underwater fault

What is the classification of a wave with a wavelength of 27 meters in water that is 30 meters deep?

deep-water wave

Which breaker type is associated with a gently sloping ocean bottom?

spilling

What kind of wave interference occurs when there are alternating high and low waves?

mixed interference

The bending of waves as they approach the shore is referred to as what?

wave refraction

What is the wave type that results in no progressive motion?

standing wave

What is the highest part of the wave?

crest

high pressure has ________ weather

colder (dry)

low pressure has ______ weather

warmer (more rain)

What is Walker Circulation?

The rising of warm air over the east-indies low pressure cell and the descent over the high pressure cell in the southeastern pacific ocean over the coast of chile. The weakening of this circulation causes a Nino year.

How might seasonal changes influence high/low pressure systems?

The movement of air and temperature changes the pressure (I AM BULLSHITTING MY WAY THROUGH THIS ONE)

How do salinity vs depth profiles vary with latitude? What drives these patterns?

Higher at surface closer at lower latitudes, lower at surface with higher latitudes. This is because of evaporation at lower latitudes and melting ice at higher latitudes.

How do temperature vs depth profiles vary with latitude? What drives these patterns?

In low-latitudes, temperature decreases with depth, but up higher it stays relatively the same, or can even increase. This is because of the air temperature outside. If it's already cold, it's gonna stay cold.

How might climate change affect ocean circulation?

Warmer temperatures can weaken currents. This will mess up the transfer of warm and cold currents, throwing things even more off-balance.

What are the characteristics and terminology used to define the anatomy of a wave?

Crests- the top of the wave
Troughs - the bottom of a wave
Still water level - halfway between the top and bottom of the wave, this is also referred to as the zero energy level
Wave height - the vertical distance between a crest and a trough

EXTRA : The horizontal distance between any two corresponding points on successive waveforms, such as from crest to crest or from trough to trough, is the wavelength, L. Wave steepness is the ratio of wave height to wavelength

What types of forces influence waves and what are some examples of each?

A disturbing force-
Air-Air, Cold fronts (high-density air) moving into an area (Ocean waves)
air-water, wind blowing on surface water (atmospheric waves)
water-water, the movement of different water densities (internal waves)

How would you describe the motion of deep water waves?

If the water depth (d) is greater than the wave base (L/2), the waves are called deep-water waves. Deep-water waves have no interference with the ocean bottom, so they include all wind-generated waves in the open ocean, where water depths far exceed wave base.

What is the difference between a deep water wave and a shallow water wave?

Deep: Circular orbits get smaller in size as they go down, making water depth greater than 1/2 a wavelength.
Shallow: Ocean floor causes the orbits to become flatter, water depth is less than 1/20 a wavelength

What are tsunamis and how are they generated?

A large destructive wave caused by sudden changes in the seafloor.

What factors control the height of wind waves?

the wind speed
the duration—the length of time during which the wind blows in one direction
the fetch—the distance over which the wind blows in one direction

Under what conditions would you expect a wave to "break"?

Usually a windspeed of 12-19 km/hr (8-12 m/hr), described as a "gentle breeze"

Are these water columns stable or unstable?
Warm with low surface salinity
Cold with high surface salinity
Cold with low surface salinity
Warm with high surface salinity

Stable
Unstable
Depends
Depends