1 Standards: S6E4b. Relate unequal heating of land and water surfaces to form large global wind systems and weather events such as tornados and thunderstorms. S6E4c. Relate how moisture evaporating from the oceans affects the weather patterns and weather events such as hurricanes. Essential Question: What factors influence weather?

2 Activating Strategy: “A Perfect Day”

3 Have you experienced a “perfect day” like Peep, Chirp, and Quack? Describe your experience. Did everyone experience the “perfect day” as you did? Why or why not? What do you think has an influence on our “perfect days”?

4 Weather refers to the state of the atmosphere at a specific time and place (short periods of time) Climate is the average weather of an area over a long period of time

5 The interaction of water, the sun, and air cause weather.

6 Turn to an elbow partner and describe what you have learned so far about the interaction of water, the sun, and air on Earth. [Hint: water cycle, land/sea breeze]

7 The Sun provides the Earth’s energy. This energy causes the evaporation of water from the atmosphere which eventually falls back to Earth as precipitation.

8 The Sun’s energy also heats the Earth’s surface, which then heats the air. Due to the unequal heating of the Earth’s surface, heat is redistributed by air and water currents.

9 Review of Concepts: S2HiYVp8 S2HiYVp8

10 As you have experienced, weather changes frequently. What factors cause weather to change?

A Few of the Factors of Weather Air Pressure Air Temperature Wind Humidity Clouds Precipitation 11

Use the Factors of Weather Graphic Organizer to Take Notes 12

13 Air temperature, wind, and humidity are all connected to air pressure.

14 Air Temperature

15 Air Temperature Temperature is a measure of the average amount of motion of molecules. Based on our previous lessons, does warm air or cold air have faster moving molecules?

As the temperature of a substance increases, the particles in the substance move faster causing lower density and lower pressure. The temperature of a substance is related to the speed of the substance’s particles. /client_ftp/ks3/science/changing_matter/chan gingmatter.swf As the temperature of a substance decreases, the particles in the substance move slower causing higher density and higher pressure.

17 Lower Temperature Higher Density Higher Pressure Lower Particle Movement Higher Temperature Lower Density Lower Pressure Higher Particle Movement

18 Infrared Images of Surface Temperature on the Earth ence/terc/content/visualizations/es1705/es 1705page01.cfm?chapter_no=visualization Notice the land specifically in the animation showing a 5 year average of surface temperatures. What concept does this demonstrate? Land heats and cools faster than water

19 Warm air temperature = Warm Feeling Weather Cold air temperature = Cold Feeling Weather

20 Wind

21 Wind is air moving in a specific direction. What determines the direction of wind?

In which direction would the wind move below. Higher Temperature faster moving particles Lower Density Lower Pressure Lower Temperature slower moving particles Higher Density Higher Pressure

23 How does wind influence weather?

24 Wind helps redistribute the Earth’s heat. Wind can make the weather in an area cooler or warmer.

25 Turn to a seat partner and describe a time you have experienced when the wind has influenced the weather.

26 Formative Assessment Check: On a sheet of paper… Identify the difference between weather and climate Describe how temperature and wind affect weather.

27 Heat evaporates water into the atmosphere. Where does it go? Water vapor molecules fit into spaces among the molecules that make up air.

Remembering the Water Cycle 28 Water Vapor Molecules

29 Humidity

30 Humidity is the amount of water vapor present in the air. le%3AThe_Water_Cycle_Watering_the_Land.ogv

Humidity Air doesn’t always contain the same amount of water vapor. More water vapor can be present when the air is warm than when it is cool. But Why??? 31

Humidity Think about it…what is happening to the movement of particles when the temperature is warm? In warmer temperatures, the particles move faster and don’t easily come together. In cooler temperatures, slower moving particles allow water vapor molecules to stick together and form water droplets of liquid water (condensation) 32

33 How then is Humidity connected to Air Pressure?

34 Cooler temperatures have lower pressure (density) and lower humidity because the water vapor condenses faster.

35 How does Humidity influence weather?

How does Humidity influence Weather? Low Humidity is when the air feels dry. 36

How does Humidity influence Weather? High Humidity is when the air feels damp, “sticky” or “muggy”. High Humidity can make the weather feel warmer than the actual temperature. 37

Would you prefer your “perfect day” weather to have low humidity or high humidity? Why? Share with an elbow partner. 38

39 Clouds Turn to a seat partner and discuss how a cloud forms.

40 A cloud forms when warm air rises, expands, cools and condenses.

41 Clouds How might clouds influence weather?

How do Clouds Influence the Weather? Clouds prevent the sun’s radiation from hitting the Earth’s surface; therefore, causing a cooling effect Clouds can also trap some of the Earth’s heat as well as reflect some of the solar radiation Clouds are a source of precipitation 42

43 Formative Assessment Check Are clouds good or bad for weather? Explain.

44 Precipitation

Precipitation occurs when water droplets combine and grow large enough to fall to Earth. Air temperature determines whether water forms rain, snow, sleet or hail 45

Precipitation 46

47 Describe a time you have experienced when precipitation has affected the weather.

48 yjams/jams/science/weather-and- climate/weather-and-climate.htm Study Jams: Weather and Climate

Summarizer: 5 – 3 – 1 Identify 5 factors of weather Describe 3 examples of how these factors affect weather Identify 1 reason weather is not the same everywhere 49