ATMS 103 Final

Doppler weather radar: Which is FALSE?

-Measures radial velocities away from and toward the radar

-Doppler velocity data is usually shown in TV weather discussions.

-The velocities are computed from the Doppler shift of the signal reflected off the moving target.

Doppler velocity data is usually shown in TV weather discussions.

Weather radar "targets" include:

-Raindrops, hail and snow

-Birds and insects

-Buildings and mountains

-All of the above

All of the above

What is the most important tool for figuring out whether a thunderstorm is a supercell?

-Simulating the storm with a computer model

-Satellite images

-Doppler weather radar

-Spotters on the ground

Doppler weather radar

The atmospheric pressure is ALWAYS:

-Proportional to the net force exerted by air molecules

striking a surface

-Equal to the weight of the air above the point in question

-Both of the above

Proportional to the net force exerted by air molecules striking a surface

Multi-cell storms last longer than single-cells because...:

-There is more CAPE, i.e., more energy available to power the storm.

-Low-level wind shear keeps the cold pool from surging out to cutoff the updraft.

-The surface temperatures and dew points are higher.

Low-level wind shear keeps the cold pool from surging out to cutoff the updraft.

Single-cell thunderstorms dissipate when...:

-They growth high enough for their tops to hit the tropopause.

-Ice starts to develop in the top of the cloud.

-The gust front spreads out cutting off the supply of warm low-level air.

The gust front spreads out cutting off the supply of warm low-level air.

There are many more thunderstorms in Florida than in Kansas, but more severe hail in Kansas. Why?

-Because the air below cloud base is DRIER in Florida.

-Because the height where the air temperature drops to 0° C is HIGHER in Florida.

-Both of the above.

Because the height where the air temperature drop to 0º C is Higher in Florida.

Thunderstorms with ice visible in the upper part of the cloud are likely to start raining very soon.

True

False

True

Virga is rain that never reaches the ground because it...:

-Gets caught in a updraft.

-Evaporates

-Turns into hail

Evaporates

Why is rain from thunderstorms often made of larger raindrops than the average Seattle wintertime raindrop?

-Because thunderstorms have very strong updrafts.

-Because thunderstorms are short lived.

-Because of the winds at the gust front.

Because thunderstorms have very strong updrafts.

What limits the maximum size of the very largest raindrops?

-The time available for it to grow before it hits the ground.

-Competition for water vapor from nearby drops.

-Aerodynamics

Aerodynamics

Concerning U.S. flash flood fatalities...:

-Almost 50% are vehicle related

-Majority are male

-Both of the above

Both of the Above

Why does a line of cloud often form above the gust front?

-The air is cooled by contact with the cold air behind the gust front.

-Warm moist air is lifted as cold air spreads outward at the gust front.

-The air is moistened by the high relative humidity behind the gust front.

Warm moist air is lifted as cold air spreads outward at the gust front.

Downdraft speeds would be increased by...:

-Increasing the environmental humidity around the sides of the storm

-Increasing the lightning flash rate

-Increasing the number of falling raindrops

-All of the above

increasing the number of falling raindrops

After unsaturated air mixes with cloudy air at the same temperature, the mixture...:

-Contains less liquid water

-Becomes colder

-Both of the above

-Neither of the above

both of the above

What happens when the rain-cooled air hits the ground?

-It bounces back up and spreads out well above the ground.

-It spreads out horizontally along the ground.

it spreads out horizontally along the ground

Air is warmed at the surface, but is not allowed to rise. Will the warming of the air tend to form a cloud?

-Yes

-No

No

Why does lightning occur most frequently between noon and 2 PM over the Florida Peninsula?

-The hottest time of the day is typically between noon and 2 PM.

-The dew point hits its daily minimum between noon and 2 PM.

-Converging air currents, flowing off the water as the land warms collide, to trigger thunderstorms.

Converging air current, flowing off the water as the land warms collide to trigger thunderstorms

Why can't we expect a deep dry-unstable layer to be the main way we get instability aloft on thunderstorm days?

-Because then there would be no clouds aloft.

-Because minor disturbances would trigger motions in the unstable layer that would remove or greatly reduce the instability.

Because minor disturbances would trigger motions in the unstable layer that would remove or greatly reduce the instability.

Why are the severe weather statistics biased toward areas with trees?

-Fewer people live where there are trees.

-Trees show high-wind damage better than grasslands.

-Tree emit more moisture than grasslands during photosynthesis.

Trees show high-wind damage better than grasslands

Why do thunderstorms "stop rising" when they reach the tropopause?

-Because the stratosphere is very stable.

-Because the troposphere is very unstable.

-Because the stratosphere is very dry.

Because the stratosphere is very stable.

In which layer is the atmosphere most stable?

-The mesosphere

-The stratosphere

-The troposphere

The stratosphere

The moist adiabatic lapse rate is less than the dry adiabatic lapse rate. (The lapse rate is the rate at which temperature DECREASES with height.)

-True (cloudy parcel cools more SLOWLY than unsaturated parcel)

-False (cloudy parcel cools more RAPIDLY than unsaturated parcel)

True (cloudy parcel cools more SLOWLY than unsaturated parcel)

The environmental lapse rate is 5° C per km. A dry air parcel given an initial push downward from a height of 1 km will tend to keep moving downward.

-True

-False

False

Why aren't there clouds in the descending air in the cumulus example?

-Because there is no water vapor in this part of the sky.

-Because the relative humidity in the descending air is a constant 100%.

-Because descending air warms as it is compressed by higher pressures in the surrounding environment.

Because the descending air warms as it is compressed by higher pressures in the surrounding environment.

Why is the burning match dropped into the bottle?

-To heat the air

-To make the experiment look more interesting

-To increase the number of CCN in the bottle

To increases the number of CNN in the bottle.

What is most FUNDAMENTALLY responsible for condensation and evaporation of the alcohol droplets in the bottle?

-Changes in temperature

-Changes in pressure

Changes in Temperature

As Steve pumps air into the bottle, the temperature of the gases inside the bottle

-Decrease

-Increase

-Stay the same

Increase

Which is NOT a reason why lightning death rates in Malawi are so high compared to the US?

-Better reporting of all lighting deaths in the US.

-Better medical care in the US.

-Smaller percentage of the population working outside in the US.

-Fewer buildings with plumbing and electrical wiring in the US.

Better Reporting of all lightning deaths in the US.

Why is squatting better than lying flat on the ground during a lightning storm? It reduces the chance of being killed by...:

-A direct strike

-A side flash

-Ground current

Ground current

If caught outside during a lightning storm with no shelter around, you should lie flat in the lowest spot available.

-True

-False

False

In the US, men are killed by lightning ______ as often as women.

-Twice

-Four times

Four times

Cars provide safety from lightning because they are insulated from the ground by their tires.

-True

-False

False

Ice plays a key role in thunderstorm electrification.

-True

-False

true

Why do you see lightning before you hear thunder?

-Because it takes a while for noise to be produced as air is heated by a lightning bolt.

-Because sound travels much slower than light.

Because sound travels much slower than light

In general, lightning is more common over the ocean than the land.

-True

-False

false

On average, which causes the most annual deaths in the US?

-Tornadoes

-Lightning

-Floods induced by heavy rain

-Hail

Floods induced by heavy rain.

Clouds tend to dissipate if they are in a region of descending air.

-True

-False

True

Why does the inward pressure on each face of the air parcel decrease as it rises? Because the pressure in the surrounding environment

-INCREASES with height.

-IS CONSTANT with height.

-DECREASES with height.

DECREASES with height

The MAIN reason rising air cools is that it comes into contact with colder air aloft.

-True

-False

False

Steam fog tends to form over water when:

-The sky is blue

-Atmospheric pressures are unusually low

-The air is very cold

-Music is playing

The air is very cold.

Thunderstorms are fueled by latent heat released when water vapor condenses to form droplets. Other factors being equal, which region is more likely to support thunderstorms?

-Surface dew point is 12° C

-Surface dew point is 22° C

Surface dew point is 22º C

Increasing the temperature without adding water vapor decreases the dew point.

-True

-False

False

If air is cooled without adding or removing water vapor, the

-RH drops

-RH stays the same

-RH increases

RH increases

What is inhibiting the molecules on the liquid surface from flying off as vapor?

-Molecular bonds

-Gravity

Molecular bonds

What is the saturation vapor pressure at 100° C?

-113 mb

-513 mb

-1013 mb (sea level pressure)

-1513 mb

1013 mb (sea level pressure)

Why is the air in a rising cloudy turret warmer than its surroundings?

-Because it is heated by a big natural gas burner.

-Because air warms as it rises.

-Because latent heat is released as water vapor condenses to form cloud droplets.

Because latent heat is released as water vapor condenses to form cloud droplets.

When heat (energy) is added to boiling water, what does NOT happen?

-On average, the molecules vibrate faster

-On average, bonds between molecules are being broken

-Some of the water evaporates

on average, the molecules vibrate faster.

Inside the bubbles, there is only

-Air

-A vacuum

-Water vapor

-Carbon dioxide

Water Vapor

The wispy stuff is water vapor (from picture with "wispy stuff" over water)

True

False

False (water vapor is clear)

It's raining hard. There's thunder. Should you take shelter under a tree?

-Yes

-No

NO

Aftermath did NOT include

-300,000 to 500,000 deaths

-25% of East Pakistan flooded

-Efficient delivery of international aid

-Civil war

Efficient delivery of international aid.

A parcel of air is buoyant and will rise if it is _______ than the surrounding environment.

-Moister

-Warmer

-Drier

-Colder

Warmer

An air parcel is a hypothetical blob of air similar to the air in a _______, because _______.

-copper box; heat can easily be transferred between the air inside and the environment, keeping them at the same temperature.

-sturdy wooden box; the air inside will maintain the same pressure while the pressure in the surrounding environment changes.

Correct!

-flexible plastic balloon; air inside will adjust its pressure to the environment

-limp plastic balloon with a hole in the bottom; water vapor can be exchanged with the environment through the hole.

flexible plastic balloon; air inside it will adjust its pressure to the environment

Averaged over the entire year, which of these locations experiences the most lightning?

-The northern midlatitudes, which includes Canada, Europe, and Russia

-The North and South Poles

-The middle of the Pacific Ocean

-Land near equatorial oceans

Land near equatorial oceans

Of the four regions labeled below, which is the main charging region for lightning?

-Region A (the top of the storm, below -40 C)

-Region B (the middle of the storm, between -10 C and

-20 C)

-Region C (the bottom of the storm, above 0 C)

-Region D (the ground)

Region B (the middle of the storm, between -10 C and -20 C)

True or false: a cloud that contains only water vapor and rain can produce lightning.

-True

-False

False

Which Spanish colony in the Americas was protected from a French invasion because of a hurricane?

-St. Augustine (in present-day Florida)

-Veracruz (in present-day Mexico)

-Santo Domingo (in the present-day Dominican Republic)

-Havana (in present-day Cuba)

St. Augustine (in resent day Florida)

You observe a large thunderstorm on the slope of a mountain as in the image. For this thunderstorm to be possible, the rising air must be _______ than the environment and the atmosphere was _______.

-Colder; stable

-Warmer; stable

-Colder; conditionally unstable

-Warmer; conditionally unstable

Warmer; conditionally unstable

How do cloud condensation nuclei (CCN) work to create cloud droplets?

-They serve as surfaces onto which water vapor can condense

-They are sources of water vapor and help to humidify the atmosphere

-They have a lower temperature than the environment and are this closer to the dew point

-None of the above

The serve as surfaces onto which water vapor can condense.

One of the ways in which cumulus clouds differ from stratus clouds is that:

-Stratus clouds form as a result of air cooling to the dew point as it rises while cumulus clouds form when isolated regions of low pressure develop

-All of the air in stratus clouds moves upward at the same rate while air inside cumulus clouds travels upward at different rates, with some air rising rapidly

-Stratus clouds form when the atmosphere is unstable while cumulus clouds form when the atmosphere is stable

-There are none; stratus clouds and cumulus clouds form under the same conditions

All of the air in stratus clouds moves upward at the same rate while air inside cumulus clouds travels upward at different rates, with some air rising rapidly

This satellite image shows ship tracks in the clouds off the coasts of France and Spain. How do ships cause these features?

-Spray from the ships crashing through ocean waves humidifies the atmosphere

-Turbulence from the ships moving through the wind creates upward motion

-The ships' exhaust provides additional cloud condensation nuclei for cloud droplets to form on

-Heat from the smokestacks destabilizes the atmosphere

The ships' exhaust provides additional cloud condensation nuclei for cloud droplets to form on

The environmental lapse rate is 12C per kilometer and the adiabatic lapse rate is 10C per kilometer. If a parcel is forced to rise, it will _______ because the atmosphere is _______.

-Return to its original elevation; stable

-Return to its original elevation; unstable

-Continue to rise; stable

-Continue to rise; unstable

continuer to rise; unstable

Which of the following lightning scenarios is least likely to be deadly?

-Standing next to a wired fence during a lightning storm

-Lying in an open field when lightning strikes a nearby tree

-Sitting, while not touching metal, in a metal-top car that is directly struck by lightning

-Using cabled electronics inside a house with plumbing and electricity when lightning strikes nearby

Sitting, while not touching metal, in a metal-top car that is directly struck by lightning

True or false: condensation can occur even if the atmosphere is stable.

-True

-False

true

What causes thunder?

-The stepped leader meeting a streamer from the surface

-Exploding hailstones

-The rapid expansion of air as it is heated by a lightning stroke

-Thunderclouds colliding

The rapid expansion of air as it is heated by lightning

Compared to a dry air parcel with no water vapor, a moist parcel in the same environment is most likely to rise adiabatically if its relative humidity is

-10 %

-50 %

-100 %

-Relative humidity has no effect on whether a parcel rises adiabatically

100%

Where in the United States would you be most likely to witness lightning?

-Orlando, Florida

-Los Angeles, California

-Seattle, Washington

-Boston, Massachusetts

Orlando, Florida

Why does the top of a thundercloud spread out horizontally into an anvil?

-The positive charges lofted to the cloud top on ice crystals repel each other

-Cloud particles grow too large to ascend any farther and are carried horizontally

-The buoyant updraft encounters the stable air of the stratosphere

-At the top, water droplets freeze to ice, which occupies more volume

The buoyant updraft encounters the stable air of the stratosphere

What is the mechanism by which electrical charges develop in a thunderstorm cloud?

-Ice particles gain positive charge when they collide with cloud water droplets

-Falling graupel and hail collide with rising small ice crystals

-Cosmic rays from the sun induce a positive charge at the top of the cloud

-Cold water droplets at the top tend to have a positive charge, while warm droplets have a negative charge

Falling graupel and hail collide with rising small ice crystals.

Where do red sprites occur?

-Above the thunderstorm

-Inside of the thunderstorm

-Under the thunderstorm

-As a horizontal connection between two thunderstorms

Above the thunderstorm

Both a saturated air parcel and a completely dry air parcel start at the surface and have the same temperature. Both parcels rise 1 kilometer. After reaching 1 kilometer, which air parcel has cooled more?

-The dry air parcel

-The saturated air parcel

-Both air parcels have cooled the same amount

The dry air parcel

For single-cell thunderstorms, the primary cause of their dissipation is

-The thunderstorm using up all the environmental moisture near the surface

-The thunderstorm using up all the environmental moisture aloft

-Cold pools spreading out below the thunderstorm, cutting off access to warm air

-The thunderstorm encounters a very stable layer at the tropopause

Cold pools spreading out below the thunderstorm, cutting off access to warm air

Which of the following is NOT a potential trigger for a thunderstorm?

-Lifting of air over a mountain range

-Heating the surface

-Lifting of air over an atmospheric front

-Addition of cloud condensation nuclei (CCN)

Addition of cloud condensation nuclei (CCN)

n 1609, the Sea Venture left England and sailed toward Jamestown, Virginia. During its voyage, the ship was crippled in a hurricane and ultimately ran aground just off the shore of Bermuda. What did NOT happen after this?

-Most of the crew and passengers died before they reach the island

-Bermuda was found to be habitable and a good place for settlers.

-Not long afterward Bermuda then become a British colony

-The story was used as the basis for Shakespeare's play, The Tempest

Most of the crew and passengers died before they reach the island

Out of the following moist air parcels located inside the thunderstorm in the image below, which one will experience the least amount of dry air entrainment?

-Parcel 1 (the top of the updraft)

-Parcel 2 (the side of a growing updraft)

-Parcel 3 (the center of the updraft)

-Parcel 4 (a region where the cloud is no longer "puffy")

Parcel 3 (The center of the updraft)

Which of the following will lessen the effects of entrainment in a localized region?

-Decreasing the dew point throughout the region where the air parcels are rising

-Warming the region, thereby increasing the saturation vapor pressure

-Continuous ascent of moist air parcels over the same region

-None of the above

Continuous ascent of moist air parcels over the same region

What commonly triggers a single cell thunderstorm?

-An isolated region at the surface reaches saturation, forming the initial cloud

-Single cell thunderstorms are triggered randomly. We do not know what triggers them

-Solar heating of the surface, which is then transferred to the air near the ground

-Dry air mixing with moist air

Solar heating of the surface, which is then transferred to the air near the ground.

Which of the following is the single deadliest storm in the Western Hemisphere?

-The Great Hurricane of 1780

-Solano's Hurricane

-The Galveston Hurricane

-The Savanna-La-Mar Hurricane

The Great Hurricane of 1780

Which factor(s) caused the Big Thompson Flood in Colorado on July 31, 1976?

-Stationary thunderstorms that produced 12 inches of rain in 4 hours

-The steep canyon walls absorbed little of the water

-A manmade dam broke and produced a 40-foot tall wall of water

-(a) and (b)

-(b) and (c)

(a) and (b)

The sea level temperature in Seattle is 25C. A dry parcel is lifted from sea level to an altitude of 1 kilometer, where the air temperature is 17C. What happens to the parcel?

-It continues to rise

-It returns to sea level

-It remains at 1 kilometer

-There isn't enough information to tell

it returns to sea level

Microbursts are a notorious danger to aviation safety. Which of the following statement about microbursts is NOT true?

They are difficult to forecast because of their small scale and sudden onset.

They are most dangerous when jet airplanes are taking off or landing

Most of the aircraft incidents that have been attributed to microbursts involve multiple lightning strikes to the airplane.

Strong microbursts can also damage trees and buildings.

Most of the aircraft incidents that have been attributed to microbursts involve multiple lightning strikes to the airplane.

Why are dry-unstable temperature profiles uncommon in nature?

-Because thunderstorms cause cooling in the lower atmosphere through evaporation of raindrops

-Because the absorption of ultraviolet light by ozone warms the stratosphere

-Because small random vertical motions would cause air parcels to start ascending and descending, releasing and ultimately eliminating the instability

-Because solar heating at the surface maintains large lapse rates

Because small random vertical motions would cause air parcels to start ascending and descending, releasing and ultimately eliminating the instability

The Caribbean was struck by three intense hurricanes in 1780. Which of the following occurred as a result of these storms?

-The Caribbean obtained a reputation for being dangerous

-A period of economic and cultural decline began

-England abandoned all of its Caribbean colonies

-(a) and (b)

-All of the above

(a) and (b)

_______ is present prior to the development of severe thunderstorms because it prevents the conditional instability of the atmosphere from being used before conditions become extreme.

-Entrainment

-High low-level moisture as measured by the dew point

-Convective available potential energy (CAPE)

-Convective inhibition (CIN)

Convective inhibition (CIN)

How do downdrafts develop in single cell thunderstorms?

-Precipitation evaporates below cloud base, which causes the air beneath the storm to cool and sink

-Falling precipitation drags air downward

-Dry air is entrained through the sides of the cloud which causes air inside the cloud to cool as droplets evaporate

-All of the above

All of the above

Which of the following "ingredients" are not required to form single cell or "air mass" thunderstorms?

-High wind speeds throughout the potential depth of the thundercloud

-High surface dew points

-A "trigger" to release atmospheric instability by creating vertical motion

-Conditional instability aloft

High wind speeds throughout the potential depth of the thundercloud

What does convective available potential energy, or CAPE, tell us about thunderstorm development?

-It measures how much moisture can become rain.

-It determines the energy that rising air parcels can release.

-It indicates how difficult it would be for air parcels lifted from the surface to become positively buoyant.

-It measures the probability that an event will be present to trigger a thunderstorm.

it determines the energy that rising air parcels can release.

If the temperature of an air parcel is warmer than its surroundings, its density must be less than that of its surroundings because the parcel and the environment always have the same _______.

-Convective available potential energy (CAPE)

-Convective inhibition (CIN)

-Pressure

-Humidity

pressure

Following the Galveston Hurricane on 1900, Galveston:

-Was rebuilt, but was never as prominent or as prosperous as before

-Built a 10-mile-long seawall

-Raised the elevation of the city

-All of the above

All of the above

Which measure of Atmospheric moister indicates how close an air parcel is to saturation?

-Water Vapor

-Relative Humidity

-Dew Point

-None of the above

Relative Humidity

Unsaturated air parcels cool at the dry adiabatic lapse rate. Saturated air parcels cool at the moist adiabatic rate. Why is the moist adiabatic lapse rate less than the dry adiabatic lapse rate?

-Saturated parcels have a higher pressure than unsaturated parcels when they rise, so they cool less.

-Saturated air parcels have a lower vapor pressure than unsaturated air parcels

-Saturated air parcels are cooled less by entrainment than unsaturated air parcels.

-Condensation occurs as a saturated parcel rises; this releases latent heat and prevents the saturates air from cooling as rapidly as an unsaturated parcel.

Condensation occurs as a saturated parcel rises; this releases latent heat and prevents the saturates air from cooling as rapidly as an unsaturated parcel.

Two air parcels are located near sea level. These parcels contain the same mass of moist air(i.e., the same total number of air and water vapor molecules). Which of the following properties can, by itself, be used to identify the parcel containing the largest number of water vapor molecules.

-temperature

-dew point

-relative humidity

-saturation vapor pressure

Dew point

True or False: In the tropics, thunderstorms are more likely over land than over ocean.

-True

-false

True

The dry adiabatic lapse rate is 10ºC per Kilometer. Assume the moist adiabatic lapse rate is 6ºC per kilometer. Suppose the environment lapse rate it 7ºC per kilometer. If lifted a short distance adiabatically, a dry air parcel will ____________ and a saturated parcel will ________.

-Returns to its original position; return to its original position.

-Return to its original position; continue to rise

-continue to rise; continue to rise

-continue to rise; remain where it is

Return to its original position; continue to rise

Which of the following describes the dissipating sage of a single-cell thunderstorm?

-Only downdrafts are present; all the warm, moist air had been cut off from the storm due to the spreading cold pool.

-Only updrafts are present; no precipitation is falling

-Both updrafts and downdrafts are present; precipitation is falling

-None of the above

Only downdrafts are present; all the warm, moist air had been cut off from the storm due to the spreading cold pool.

Latent heat is _____ when water vapor condenses into liquid water because the bonds between molecules are _____.

-absorbed; breaking

-absorbed; forming

-released; breaking

-released; forming

-released; forming

Which of the following is one of the ingredients necessary to produce all types of thunderstorms?

-Strong low-level wind shear

- a stable atmosphere

-Abundant low-level moisture

-Warm temperatures aloft

Abundant low-level moisture

Microbursts are most dangerous to...

-Cars on highways

-hot air balloons on clear calm mornings

-small propeller-driven planes cruising a few feet above the ground

-Large jet aircraft attempting landings

large jet aircraft attempting landings

When an unsaturated parcel of air is lifted from the ground, it cools because...

-the atmospheric environment temperature decreases with height and the parcel cools through contact with the surrounding air

-The atmospheric density increases with height and parcel cools so that its density matches that of the surrounding air.

-The atmospheric environment temperature decreases with height and colder air mixes with the air parcel, expanding and cooling it

- atmospheric pressure decreases with height so the air parcel expands and the air molecules within the parcel lose energy during the expansion.

atmospheric pressure decreases with height so the air parcel expands and the air molecules within the parcel lose energy during the expansion.