Chapter 8

5th Grade ScienceWeather Patterns

Layers of Air

• ______ - made up of 8/10 nitrogen and 2/10 oxygen, small parts of carbon dioxide, water vapor and other gases

• _______ of Earth’s atmosphere• Most weather conditions occur in the

________ layer – troposphere• ___________ and ___________ change

through the layers

Air

5 layers

bottom

temperature Air pressure

5 Layers

• Air pressure __________ as you go ___ through the atmosphere– Gas particles get _______ apart and there is _____ air

above5 Layers:1. ___________ - Highest layer2. ___________ -3. ____________4. _____________5. ______________ - bottom layer

decreases up

farther less

ExosphereThermosphereMesosphereStratosphereTroposphere

Heating and Cooling Earth

• Land heats up _____ than water in the sun• Land cools _____ than water• Air above land and water have different

____________.• Differences in temperatures cause:– _________– _________– ___________________

faster

faster

temperatures

winds

storms

Other sorts of weather

Convection Current

• ______________ - caused by different temperatures – gases and liquids rise and sink in a circular pattern.

• ______ - gas particles are closer together than in warm air– Cooler air is _________ than warm air– Cool air _______ and lets the warm air ______

above it

Convection current

Cool air

heavier

sinks rise

6 Convection Currents

• __________________ form above the Earth• Warm air from the _______ rises and then

cools as it moves north and south• ______________________ - the combination

of movement of huge convection currents and the spinning of the Earth on its axis

• Winds blow from _______ to _______

6 huge convection currents

Tropics

Regional surface wind patterns

West East

Jet Streams

• _________ - found high above the ground between the 6 huge convection currents– Band of very fast ________ formed by different

temperatures between convection currents– Causes changes in ______, ___________, and

____________ by affecting the movement of air

Jet Streams

winds

wind temperatureprecipitation

Study Diagram on Page 232-233

Air Masses

• __________ - large body of air with similar properties (_________ and ______________) all through it

• Air masses move because of ______• Some air masses are guided by the _________• At the edge of an air mass, _______ may occur• There are __ kinds of air masses – the kind of

weather depends on the air mass in that area.

Air Massestemperature Amount of Water vapor

winds

Jet Streams

storms

4

4 Air Masses

• ________________ - air mass from this area is cold and fairly dry because the land near the poles is not very moist

• ________________ - humid air with lots of moisture because of evaporation over tropical oceans and rainforests

• _________________ - air is cold and moist because cold ocean water near the poles evaporates

• _________________ - warm and fairly dry from hot desert air

Continental Polar Air

Maritime Tropical Air

Maritime Polar air

Continental Tropical Air

Fronts

• ________ - a boundary between two air masses

• Air masses and fronts move from _____ to ____ across the United States

• A ______ gets its name from the kind of air that moves into the area.

• Example: cold front = ______, warm front =_________

Front

westeast

front

Cold airWarm air

Fronts Continued

• _____________ - a front that does not move very much or it moves back and forth over the same area.

• Areas of rising air near fronts have ______________ than areas in the middle of air masses

• Rising air masses at fronts often cause ____________

Stationary front

Lower air pressure

Rain or snow

Cold Front / Warm Front

• __________ - cooler air moves into an area and forces warmer air to move upwards quickly

• The rising air forms ___________ along the steep boundary

• Heavy precipitation often falls near a _______• ________ - warmer air moves against cooler air.

Warmer air rises above the cooler air• Clouds of a warm front often move ______ and

cause longer periods of __________

Cold Front

Cumulus clouds

Cold Front

Warm Front

slowlyprecipitation

Severe Weather

• ___________ includes thunderstorms, tornadoes, and hurricanes

• __________ - caused by strong, quickly rising currents in moist air: Three stages– 1st Stage: Clouds grow as moisture _________ in

the rising air. The clouds have both __________ and ____________

– 2nd Stage – precipitation begins to fall – storm has both upward and downward _____________

Severe weather

Thunderstorms

condensesIce crystals

Water droplets

Moving currents

Watch / Warnings

• 3rd stage – all of the _________ are moving downward , the clouds get ________ as precipitation falls.

• ______________ - means that severe thunderstorms with high winds and hail might form

• ________________ - means that severe thunderstorms have formed and people should prepare for them appropriately

currentssmaller

Severe Storm Watch

Severe Storm Warning

Tornadoes

• Layers of _____ in a storm blow at different _________ or in different ________

• Between the layers, a ______ of air starts spinning.

• The spinning column of air is called a ___________

• When the funnel cloud touches the ground it is called a _______.

winds

speeds directions

column

Funnel cloud

tornado

Tornado Warning

• Tornados can move at hundreds of ________ per hour

• The winds can be strong enough to move ____ and ________.

• After a warning people should take ______ in the lowest part of a building like a __________

• No ________ near the _____ of the building

kilometers

cars

buildings

shelter

basement

windows center

Hurricanes

• Hurricanes get energy from ______________.• Water vapor from the ocean ________ and

releases ______.• Under the right condition, the ________

builds and drives the _____ of a hurricane to land.

• Once the hurricane reaches land, the ______ is reduced.

Warm ocean waters

condensesenergy

energy

winds

energy

Hurricane Warning

• Winds of a hurricane are __________ as a tornado, but they can be more ________.

• To prepare for a hurricane, people must ________________, ___________, and ________

• Flashlights and battery powered radios• Most important – STAY INSIDE or leave if the

authorities call for an evacuation

Not as fast

destructive

Board up windows Store foodwater

Weather Instruments

• ________ - shows air pressure• ___________ - measures wind speed – wind

makes the cups of the instrument spin around• ________ - measures moisture in the air• ___________ - measures how much rain has

fallen• _______ - measures the winds and

precipitation during a storm

barometer

anemometer

hygrometer

Rain gauge

radar

Weather Predictions

• ______________ - observe patterns of weather change and make _________

• _________ - conclusions of how air, land, and the steps of the water cycle affect each other to make ___________.

• Forecasters make ________ about the weather in the future based on their ________

Weather forecasters

inferences

inferences

Weather systems

predictions

inferences

Forecasts

• Forecasters make predictions by assuming that _______ weather conditions will behave like similar weather in the _____

• Forecasters use __________ to display the data• Triangles and circles point in the direction that

the _____ is moving• Fronts are always in places of __________• ___________ = clear skies

currentpast

Weather maps

front

Low pressure

High pressure

Climate

• _______ - the average of weather conditions over a period of time

• Climate includes the average amount of ___________, the average ________, and how much ___________ changes over a period of time.

• __________ and _________ are not the same thing – climates do not change, weather changes.

Climate

precipitation temperaturetemperature

Climate weather

Landforms affect Climate

• Higher land is ________ because temperatures ________ with height in the troposphere.

• _________ on opposite sides of a mountain vary.

• The ______ side of the mountain gets more precipitation than the ____

• ________ can affect a climate by slowing the rise and fall of the air temperature

coolerdecrease

Climates

westEast

Oceans

Oceans and Climate

• The temperature of air on land warms and cools faster than the temperature of the air over an ocean.

• _____________ can make climate warmer or cooler

• ________________________ are large currents that carry warm water northward

• The water warms the _____ above it• __________ - make the coastal climate cooler

Ocean currents

Gulf Stream and North Atlantic Drift

winds

Cold Currents

Climate Change

• ________ have changed throughout history• _______ help scientists make assumptions

about ancient climates• Climates can change as the result of:– ______________– _______________________– _____________________

Climates

fossils

Volcanic EruptionsAsteriod or meteorite impacts

Burning coal and gasoline