Chapter 21 Flashcards by Mary Catherine

Air moves from ___ pressure to ___ pressure.

high

low

How well did you know this?

Not at all

Perfectly

a large body of air throughout which temperature and moisture content is similar

air mass

How well did you know this?

Not at all

Perfectly

What are the four types of air masses?

cT
cP
mT
mP

How well did you know this?

Not at all

Perfectly

What are the three tropical air masses?

Maritime tropical Pacific (mT),
Continental tropical (cT),
Maritime tropical Atlantic (mT)

How well did you know this?

Not at all

Perfectly

What are the three polar air masses?

Maritime polar Pacific (mP),
Continental polar Canadian (cP),
Maritime polar Atlantic (mP)

How well did you know this?

Not at all

Perfectly

the boundary between air masses

front

How well did you know this?

Not at all

Perfectly

cold air mass pushes under a warm air mass like a wedge

cold front

How well did you know this?

Not at all

Perfectly

What type of clouds form during a cold front?

large cumulus, cumulonimbus clouds

How well did you know this?

Not at all

Perfectly

What happens during a fast-moving cold front?

large, violent thunderstorms

How well did you know this?

Not at all

Perfectly

the line of heavy thunder storms

squall line

How well did you know this?

Not at all

Perfectly

What happens during a slow-moving cold front?

weaker storms and light precipitation

How well did you know this?

Not at all

Perfectly

warm air mass moves over a cold mass

warm front

How well did you know this?

Not at all

Perfectly

What happens during a warm front?

gradual front slope, clouds spread ahead and cover a large area, precipitation covers large area, violent weather is occasionally caused

How well did you know this?

Not at all

Perfectly

front of an air mass that moves very slowly or not at all

stationary

How well did you know this?

Not at all

Perfectly

cold air mass moves under a warm air mass and lifts the warm mass completely off the ground

occluded

How well did you know this?

Not at all

Perfectly

During a polar front cold air mass sits over each pole until about ___ degrees latitude.

How well did you know this?

Not at all

Perfectly

air sinks and flows out from a high pressure center

anticyclone

How well did you know this?

Not at all

Perfectly

bend that forms in a cold front or a stationary front

wave

How well did you know this?

Not at all

Perfectly

areas of low pressure that are characterized by rotating wind, which moves toward the rising air of the center, low pressure region

midlatitude cyclones

How well did you know this?

Not at all

Perfectly

Midlatitude cyclones usually last ___ days, travel at a speed of ___ km/h in a ___ direction, and spin ___.

several
45
easterly
counterclockwise

How well did you know this?

Not at all

Perfectly

the boundary where cold air meets warm tropical air

polar front

How well did you know this?

Not at all

Perfectly

Which direction do anticyclones spin in? Why? Where?

clockwise
because of the Coriolis effect
northern hemisphere

How well did you know this?

Not at all

Perfectly

What do anticyclones bring?

dry, clear weather

How well did you know this?

Not at all

Perfectly

What could happen if anticyclones stay too long?

they could cause pollution or drought

How well did you know this?

Not at all

Perfectly

brief, heavy storms that have rain, strong winds, lightning and thunder

thunderstorms

What are the three stages of a thunderstorm?

1. cumulus 2. mature 3. dissipating

What happens in the first stage of a thunderstorm?

Cumulus- warm, moist air rises, water vapor condenses and forms cumulus clouds

What happens in the second stage of a thunderstorm?

Mature- clouds rise and form cumulonimbus clouds, heavy rainfall and hail may fall, strong up and down drafts

What happens in the third stage of a thunderstorm?

Dissipating- downdrafts stop the fresh supply of water vapor from rising, clouds dissipate

the discharge of electricity

lightning

In lightning, the upper part of the cloud carries a ___ charge & the bottom carries a ___ charge.

positive | negative

Where are the three places lightning may form?

1. inside a cloud 2. between clouds 3. between a cloud and the ground

How is thunder formed?

air around lightning super heats and expands rapidly, causing the loud noise

Lightning forms as electrons flow from ___ to ___ to ___ the charge.

positive negative equalize

A ___ is a tropical storm with wind speeds over ___ km/h that spiral around a ___-pressure storm center.

hurricane 120 low

What two things must a hurricane have to form?

1. form over a warm tropical ocean | 2. have the Coriolis effect

What is the process of a hurricane?

Warm, moist air rises and condenses, releasing energy as latent heat. Latent heat adds strength to rising air.

What is the eye of a hurricane?

came, clear sinking air

What happens during a fully-developed hurricane?

thick cumulonimbus cloud bands spiral around the center of the storm

What is the most destructive type of storm?

a hurricane

the rising sea level in front of a hurricane that causes flooding

storm surge

What are most hurricane deaths from?

drowning

rates hurricane intensity from 1-5

Saffir-Simpson scale

What three things does the Saffir-Simpson scale measure?

1. central pressure 2. wind speed 3. storm surge

A ___ is a destructive, rotating column of air with very high wind speeds (up to ___ km/h).

tornado | 400

What may a tornado be visible as?

a funnel-shaped cloud

smallest, most violent and short-lived storm

tornado

How does a tornado form?

when a thunderstorm meets high altitude horizontal winds that make it rotate

Texas through midwestern United States, tornadoes most common here from late spring to early summer

Tornado Alley

What are most tornado injuries/deaths caused by?

people in collapsed buildings, or | being struck by objects that are blown by the wind

a program designed to promote rapid exchange of weather information (it helps developing countries establish or improve their meteorological services)

World Weather Watch

What organization promotes the World Weather Watch? What's its abbreviation?

The World Meteorological Organization (WMO)

What do weather maps allow meteorologists to do?

1. understand current weather patterns | 2. predict future weather events

What do meteorologists use to communicate weather data on a weather map?

symbols & colors

a pattern of meteorological symbols that represents the weather at a particular observing station and that is recorded on a weather map

station model

What does a station model show?

cloud cover, wind speed, wind direction, weather conditions, dew point, temperature, atmospheric pressure, and barometric tendency

Lines on weather maps connect points of ___ measurement.

equal

lines that represent equal temperature

isotherms

lines that represent equal pressure

isobars

What do closely spaced lines indicate?

a rapid change in pressure, | high wind speeds

What do widely spaced lines indicate?

gradual change in pressure, | low wind speeds

What is precipitation commonly shown with on a weather map?

colors/symbols

___ and ___ provide data that computers use to create weather models.

Doppler radar | satellite images

daily forecasts

48 hour range

extended forecasts

3-5 days

medium-range forecasts

3-7 days

long-range forecasts

7 days, monthly, seasonally

What is the goal of weather warnings?

to reduce the amount of destruction caused by severe weather, by forecasting severe weather early

issued when conditions are ideal for severe weather

Watch

issued when severe weather has been spotted (thunderstorms/tornadoes), or is expected within 24 hours (snowstorms/hurricanes)

Warning

What is the most researched method for producing rain?

cloud seeding