Spring 2023 GEOL 215/ MSCI 215 Test 2

_________ refers to the movement of sand grains along the beach

Longshore drift

Which of the following atmosphere and ocean characteristics are necessary for hurricane formation?

(All of the above) 1. Sea surface temperature higher than 27°C 2. Light winds, which allows convection to organize 3. Convergence at the surface, which causes rising air

To measure sea level rise which of these instruments we use:

(All of the above) 1. Tide gauge 2.Argo buoys 3. Satellites (altimeter, GRACE)

The height of an ocean wave increases as

(all of these) 1. the wind speed increases 2. the wind blows for longer times 3. the distance over which the wind flows over the water increases

Under ideal conditions and in most places on Earth, the time between a high tide and the next high tide is:

12 Hours, 25 minutes

How many high tides are there in a day in the US SE?

2

Fifteen (15) waves with a wavelength (L) of 30m passed through a stationary point over a time period of 30s. What is the period (T) of the waves?

2 sec

What is the current rate of global sea level rise?

3.7 mm/year

Ripples in the ocean grow to full-sized waves when the wind reaches a speed of about per hour.

30 kilometers

The distance between a crest and the adjacent trough of a wave is 15m. What is the wavelength of this wave?

30 m

What percentage of the world's population lives within 100 km of the shoreline:

39%

In the North Atlantic, the tidal wave turns around the amphidromic point in

A counterclockwise position

A tsunami is

A large wave caused by an undersea event AND an earthquake which causes a long wave

The reason that a lunar day is _______ a solar day is because _______

A= longer than; B = the moon is also moving along its orbit around Earth.

Neap tides

All of the above: 1. Occur when Sun, Moon and earth are right angles 2. Occur every first and third quarter of moon 3. Have lower tidal range than spring tides

The point around which tidal crests and troughs rotate is known as

Amphidromic point

What is the largest source of ice melt?

Antarctica

On average, what are the peak months of the hurricane season?

August/September

Assume two straight beaches A and B, respectively. Waves approach the coastline A with an angle of approach (i.e., angle between wave crest and shoreline) approx. 20degs. The same waves travel toward beach B and approach the coastline with an angle of approximately 5 degrees. Which beach experiences stronger longshore currents and consequently the larger sediment transport (littoral drift)?

Beach A

Plunging breakers usually occur at:

Beaches with high sloping shorefaces

What is the equation relating wave frequency (f) with wave speed (C) and wave length (L)?

C=L/f

The figure above shows the bathymetry of a coastal region and two cases of wave propagation (old lines shown are orthogonals: lines drawn perpendicular to the wave crest showing the path of wave propagation). which case is the correct one

Case B

In the Northern Hemisphere, which direction do a hurricane's winds rotate?

Counter-clockwise

Which type of beach is characterized by gentle beach slope?

Dissipative

In Figure 1, the tides at location B (dashed line) are:

Diurnal

Are rates of sea level rise increasing faster along the west or the east coast of the United States?

East

Water flowing out of a bay due to a change in the tides:

Ebb current or tide

Waves brake in the nearshore zone when

Either condition 1 and 2 (Wave becomes too steep, Water becomes too shallow) is reached.

In the nearshore, waves are traveling faster in shallower waters

False

The best time to go collecting at a tide pool (when there would be the lowest water level) is during neap conditions

False

What causes the tides?

Gravity

A beach that consists of gravel indicates conditions of

High wave energy

Why do hurricanes form?

Hurricanes transport excess energy in the tropics toward the poles

In the above figure, where do you expect to see larger waves?

In area B

When the tide is flooding, the sea surface elevation

Increases

What is the effect of infiltration in swash zone sediment transport?

It promotes onshore sediment accumulation and beach build up.

When is the main hurricane season in the North Atlantic?

June to November

A secular change is a _______ change?

Long term, non periodic

Gravel-sized material that is usually found in some SC beaches consists of

Oyster Shells

The tidal range in the Bay of Fundy is record-high because:

Period of seiches in the bay is the same as tidal period

12) The size of the orbit of the water particle in the question above (55) is:

Reduces with distance below the sea surface

What is the name of the scale used to rank hurricanes and measure their damage potential?

Saffri-Simpson

A sediment sample from Beach A consists of gravel, sand, and clay, while a sediment from Beach B consists of medium sand only. Which of the statements below is correct?

Sample A is badly sorted while sample B is well-sorted

What are the tides in the southeastern US?

Semidiurnal tides

The line of demarcation between the water and the exposed beach, (ie land-water interface) is called

Shoreline

The proposed relationship between climate change and hurricanes is that the total number of hurricanes will ________, but the number of more intense hurricanes (Category 4 and 5) will ______.

Stay the same, increase

Who chooses the names for tropical storms and hurricanes in the Atlantic?

The World Meteorological Organization

Which of the following does not contribute to changes in sea level?

The bathtub model

Assume a beach that is laterally confined by two headlands that do not permit any sediment transport in the alongshore. The beach is backed by eroding cliffs and has a river that discharges some 20,000m3 of sediment in one year. Cliff erosion produces some 50,000m3 of sediment per year. No significant offshore canyons exist in the area. Which scenario is more likely to be true?

The beach is accreting.

The difference between the sea water level at low and high tide is called:

Tidal Range

What would tides be like on Earth if the moon did not exist? (Hint: consider the forces involved and remember we need the sun so we can see what's going on)

Tides would continue to occur, but the tidal range will be reduced

What is the sequence of hurricane formation?

Tropical Disturbance, Tropical Depression, Tropical Storm, Hurricane

In general, the slope of the beach profile increases with the sediment size.

True

The trough is the lowest point between two waves

True

Wave length is the horizontal distance between

Two adjacent crests

The time period between two successive spring tides is:

Two weeks

If you followed a single drop of water during a passing wave, in which motion would it move?

Vertical Circle

Other than melting glaciers and ice sheets, which of these factors has made largest contribution to the rise in sea level over the past 100 years?

Warming of Ocean Surface waters

Rip currents are:

Wave-induced currents

Waves are generated when the wind blows over a body of water. The wave height depends on:

Wind, speed, fetch and length of time the wind blows

The height of an ocean wave increases as

all of the above (the wind speed increases, the wind blows for longer times, the distance over which the wind flows over the water increases)

What do we call long offshore sandbars

barrier islands

When a wave gets close to shore, water particles near the bottom move in orbits.

elliptical

A coastal body of water connected to the ocean and supplied with fresh water from a river is a(n)

estuary

As an influence in generating tides on Earth, the sun is about twice as effective as the moon.

false

By counting the number of crests that pass in a given amount of time, a person can calculate the

frequency

In the previous question (#39 on the sample), if you know that there is a submarine canyon just offshore of that beach what would you expect? (3)

if the beach is accreting the deposition to be lower than if no canyon existed.

What part of the Earth absorbs the greatest amount of heat from the sun?

oceans

The orbital motion of water particles due to surface waves stops at a depth

of about one-half of the wavelength

The path a water particle makes a wave passes in deep water is described as

orbital

The figure above shows the "orthogonals" of a wave as it travels toward the coastline. What is the submerged topographic form in the area B?

ridge

In figure 1, the tides at location A are:

semi-diurnal or mixed

type of tide experienced in Miami

semidiurnal

What is a storm surge?

severe flooding caused by higher than normal tides

Which tidal variation produces higher tides?

spring

Which of the following landforms are caused by wave erosion?

stacks

What causes the most deaths from a hurricane?

storm surge

What is a hurricane?

storm with winds of 75 mph or more

Near a river mouth ebb tide is

stronger than flood tide

Deep valleys eroded into the continental slope and shelf are called

submarine canyons

Large fan-shaped deposits of fine-grained sediments that accumulate on the continental rise are called

submarine fans

Normally beaches will have the greatest amount of sand on the berm near the end of which period?

summer

The portion of the nearshore in which bore-like waves occur after they break is called:

surf zone

Waves run up onto the beach forming a ________, and run back down as _______

swash ... backwash

What region of the world would most likely warm most rapidly due to climate change?

the arctic

During storm periods high-energy waves strike the beach. This is when...

the berm shrinks and the longshore bar grows.

Where are the worst winds in a hurricane found?

the eyewall around the eye of the hurricane

The muddy or sandy areas that are exposed during low tide but are flooded at high tide are called

tidal flats

Period change in sea level relative to land along a coast known as

tide

What type of currents erode and deposit fine-grained sediments on the continental slope and rise?

turbidity currents

Spring tides occur, approximately

twice a month

How many high tides are there in a day along East coast US ?

two

Waves cause small particles floating on the surface to move in

vertical circular orbit

What is a major cause of hurricane formation?

warm ocean water

As waves approach a beach, the rows of waves gradually bend to a direction more parallel to the short. This change in direction is called

wave refraction

The distance between two wave crests is called the

wavelength

What is the main agent/mechanism for the creation of a dune?

winds

Is gravity necessary for the existence of the sea waves we see near the coastline (away from the wave generation area)?

yes