1. Pages 229-241

2. 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)

3. How does the water cycle affect weather? The water cycle can cause a change in humidity, visibility, and precipitation.

4. 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.

5. What are air masses? https://www.youtube.com/watch?v=kzNR_tjKExU

6. 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 follows Warm front – moves slowly, brings drizzly rain, warmer weather follows Stationary front – doesn’t move, brings precipitation for many days

7. Cold Fronts vs. Warm Fronts https://www.youtube.com/watch?v=tsD6zkBMmck

9. 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 clouds Brings stormy weather REMEMBER: Winds always blow from a high pressure to a low pressure!

10. High vs. Low Pressure https://www.youtube.com/watch?v=aiYyCurh_SU

11. 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 E  W, 60-90 latitudes Westerlies – blow from W  E, 30-60 latitudes Trade winds – blow from E  W, 0-30 latitudes Winds can bring weather that isn’t typical for an area.

12. Global Winds and Jet Streams https://www.youtube.com/watch?v=GvXPtQuQtiU

13. How do jet streams affect weather? Long distance winds that travel above the global winds They move very quickly in a wavy pattern from W  E Polar jet stream – brings cool, dry air Subtropical jet stream – brings warm, moist air Strong storms tend to form along jet streams also

14. The Jet Stream https://www.youtube.com/watch?v=CgMWwx7Cll4 https://www.youtube.com/watch?v=huweohIh_Bw

15. A Summary of the Jet Stream Jet 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.

16. 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 temperatures Winds cause ocean currents on the surface which can bring cool weather or warm weather to areas Ex: Gulf Stream – brings warm water from the Gulf of Mexico up the east coast of the US Ex: East Australian Current – brings warm water down towards polar regions, FINDING NEMO Sea Turtles used it for transportation

17. Ocean Currents https://www.youtube.com/watch?v=6vgvTeuoDWY

18. Gulf Stream https://www.youtube.com/watch?v=rR5TFWNLtOc

19. East Australian Current (EAC) https://www.youtube.com/watch?v=I-N_7cgwHmQ