Pages 229-241

How does the water cycle affect weather?

Water is constantly being recycled between liquid, solid, and gaseous states

Evaporation – Liquid to gas (forms water vapor)Transpiration – Liquid to gas FROM PLANTS (forms

water vapor)Condensation – Gas to liquid (forms clouds, fog,

dew)Precipitation – Falls from clouds* Runoff – water that flows over land (streams,

rivers)* Infiltration – seeps into the ground (ground water)

How does the water cycle affect weather?

The water cycle can cause a change in humidity, visibility, and precipitation.

How do air masses affect weather?The weather changes when a new air mass

moves into your area.An air mass is a large volume of air in which

temperature and moisture content are nearly the same throughout.

Ex: If we have a warm, humid air mass sitting on our city, we will have warm, humid weather.

What are air masses?https://www.youtube.com/watch?

v=kzNR_tjKExU

How do fronts affect weather?When two air masses meet, a boundary or

FRONT forms.The warm air is forced up, cools and condenses,

forms clouds, and allows for precipitation.Cold front – moves quickly, brings heavy rain,

cooler weather followsWarm front – moves slowly, brings drizzly rain,

warmer weather followsStationary front – doesn’t move, brings

precipitation for many days

Cold Fronts vs. Warm Frontshttps://www.youtube.com/watch?

v=tsD6zkBMmck

How do pressure systems affect weather?

In a high-pressure system, air sinks slowly down.Brings clear skies and calm air or gentle breezes

In a low-pressure system, air rises.As the air rises, it cools, condenses, and forms

cloudsBrings stormy weather

REMEMBER: Winds alwaysblow from a high pressureto a low pressure!

High vs. Low Pressurehttps://www.youtube.com/watch?

v=aiYyCurh_SU

How do global winds affect weather?

Winds are caused by unequal heating of Earth’s surface – which causes air pressure differences – and can occur on a global or on a local scale.

Global winds are:Polar easterlies – cold winds from the poles, blow

EW, 60-90 latitudes Westerlies – blow from WE, 30-60 latitudesTrade winds – blow from EW, 0-30 latitudes

Winds can bring weather that isn’t typical for an area.

Global Winds and Jet Streamshttps://www.youtube.com/watch?

v=GvXPtQuQtiU

How do jet streams affect weather?

Long distance winds that travel above the global winds

They move very quickly in a wavy pattern from WE

Polar jet stream – brings cool, dry air

Subtropical jet stream – brings warm, moist air

Strong storms tend to form along jet streams also

The Jet Streamhttps://www.youtube.com/watch?

v=CgMWwx7Cll4https://www.youtube.com/watch?

v=huweohIh_Bw

A Summary of the Jet StreamJet streams are strong upper air currents

circumnavigating the globe.There are two main jets: the polar jet and the

subtropical jet.Jet streams can fluctuate in strength between

100-200mph.The jet stream meanders in waves.

How do ocean currents influence weather?

Remember that ocean waters take a lot of energy and time to warm up or to cool down

This helps to moderate temperaturesWinds cause ocean currents on the surface

which can bring cool weather or warm weather to areasEx: Gulf Stream – brings warm water from the

Gulf of Mexico up the east coast of the USEx: East Australian Current – brings warm water

down towards polar regions, FINDING NEMO Sea Turtles used it for transportation

Ocean Currentshttps://www.youtube.com/watch?

v=6vgvTeuoDWY

Gulf Streamhttps://www.youtube.com/watch?

v=rR5TFWNLtOc

East Australian Current (EAC)https://www.youtube.com/watch?v=I-

N_7cgwHmQ