Weather & Climate

1. Weather & Climate Intro to Weather Clip

2. Weather by Brainpop 1) What cycle is the basis of our weather? 2) What causes precipitation to occur? 3) Where do storms usually occur?

3. Weather • Temporary behavior of atmosphere (what’s going on at any certain time) • Small geographic area • Can change rapidly

4. Weather • --The study of weather is meteorology • --Someone who studies weather is called a meteorologist

5. Climate • Long-term behavior of atmosphere (100+ years) • Large geographic area • Very slow to change

9. Climate Types by Brainpop • .What is climate? • .Where are tropical climates most likely to be? • .What does “arid” mean?

10. What Factors Affect Weather & Climate? • The Sun • The Water Cycle • The Atmosphere • The Ocean

11. How Does the Sun Affect Weather? • It warms the atmosphere & oceans • It creates climate zones • It keeps the water cycle going • It affects weather patterns

12. The Water Cycle • All the water on the planet is recycled in this manner!

13. Parts of the Cycle • Evaporation—Water going from a liquid to a gas (gains energy from the sun)

14. Parts of the Cycle • *Transpiration—evaporation of water from/out of plants. Locate this on the diagram! transpiration

15. Parts of the Cycle • Condensation—Water going from a gas to a liquid (cools or loses energy) • When this happens in the atmosphere, CLOUDS form.

16. Clouds by Brainpop

17. Parts of the Cycle • Precipitation—when water falls out the atmosphere. Forms when the water droplets in clouds become too heavy to stay up.

18. Precipitation • Liquid water = rain • Frozen water = snow or sleet or hail Rain Clip

19. The Water Cycle Water Cycle by Brainpop

20. Water Cycle Advanced by Brainpop

21. The Water Cycle by Brainpop • What process must happen for clouds to form? • What is “collection”? • Name one way to conserve water.

22. How does the atmosphere affect weather? • The atmosphere is a mixture of gases that surrounds the Earth • Has five different layers; each has different properties • We’ll label them in just a minute… • Air Temperature and Pressure change with altitude • Weather occurs in the layer closest to Earth (troposphere)

23. Write in the labels! Exosphere Thermosphere Ionosphere Mesosphere Ozone layer Stratosphere Troposphere

24. Earth’s Atmsophere by Brainpop • . What is ozone? • . What layer of the atmosphere does weather occur in? • . What 2 gases compose the most of Earth’s Atmosphere?

25. Air Masses • = body of air with a certain temperature and moisture level • Can be warm or cold • Can contain a lot of moisture or not a lot of moisture

26. Fronts • = places where air masses meet • 4 Types: Warm, Cold, Occluded, Stationary • Each kind can bring different kinds of weather

27. Occluded Front: Stationary Front:

29. Science Saurus 221/222 & Reading a Weather Map Worksheet

30. How does Air Pressure affect weather? • How much the earth’s atmosphere is pressing down on us • Measured with a BAROMETER • If it CHANGES, then new weather is on the way: • Falling Air Pressure = stormy weather coming • Rising Air Pressure = fair weather coming • Steady Air Pressure = no change is coming

31. Pressure Systems

32. Winds = created from differences in air pressure • Moves from areas of HIGH to LOW pressure • Greater the difference in pressure, the FASTER the wind blows • Measured with wind vanes and anemometers or you can estimate with the Beaufort Wind Scale ScienceSaurus 224/225

33. Beaufort Wind Scale

34. Winds by Brainpop • . What does warm air do? • . What do you call winds that blow all the time in the same part of the world? • . What are jet streams?

35. Relative Humidity • Measure of the amount of moisture in the air compared to what the air could hold • How “full” of water the air is • Expressed as % • 100% relative humidity = saturated air Relative Humidity Test Applet http://itg1.meteor.wisc.edu/wxwise/relhum/rhac.html

36. Relative Humidity Controlled by temperature 1. Warm air holds more moisture than cool air (more space for water vapor between air molecules) 2. As air warms, relative humidity decreases 3. As air cools, relative humidity increases

37. Dew Point • =Temperature at which the air is saturated (100% relative humidity) Several events can occur when the dew point temp. is reached: 1. If dew point temp. is above freezing: a. water vapor condenses as liquid b. dew will form on surfaces

38. Dew Point c. cloud droplets will form in air 2. If dew point temp. is below freezing: a. water vapor condenses as a solid b. frost on surfaces c. snow (or hail) in the air

39. Humidity by Brainpop • 1. What single factor controls humidity? • . What temperature air can hold the most water molecules? • . What causes water to evaporate into the atmosphere?

40. Rainbows • Caused by sunshine on raindrops • White light (all colors) is refracted (bent) into colors as it enters and exits the drop • To see a rainbow you must have the sun behind you and raindrops in the air • Diagram:

41. Rainbow by Brainpop

42. How does the Ocean affect weather? • Ocean currents affect the temperature of the land they pass by • Cold ocean currents = cooling effect • Warm ocean currents = warming effect • Temperature changes affect pressure – which then creates WINDS • Winds blow this cooling or warming effect over the land http://earth.rice.edu/MTPE/hydro/hydrosphere/topics/Ocean_Atm_Circ_ElNino.mov

43. Advanced Weather by Brainpop Violent Weather

44. Types of Storms

45. Thunderstorms Requires a mature cumulonimbus cloud Signs • Sudden reversal of wind direction • Noticeable increase in wind speed • Sudden drop in temperature

46. Thunderstorms Possible weather: a. heavy rains (flash floods) b. lightning (forest fires) c. thunder (frightens animals) d. hail (crop damage) e. tornadoes f. strong, gusty winds Thunderstorm by Brainpop

47. Safety Rules • Stay indoors • Prepare for lightning, strong winds • Listen on radio/TV for tornado watch/warning • Thunderstorms don’t last long

48. Lightning Storm Cumulonimbus cloud becomes electrically charged and ground below has opposite charge

50. Lightning stroke: flow of current thru air (a poor conductor) from the – to the + • Lightning can flow from cloud to ground, cloud to cloud, and from ground to cloud • Bright light is caused by glowing air molecules heated by the current • Lightning follows the path of least resistance (easiest way to positive) • Lightning rod offers lightning an easy, safe path to the ground (+)