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

6. POLAR
90o -60o latitude
Cool summers, cold year-round
Dry

7. TEMPERATE 60o-30o latitude True Seasons Variety of climate patterns
Moderate precipitation (rain/snow)

8. TROPICAL 30o - equator No winter, warm year-round
High temp, rainfall, humidity

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. Frozen water = snow or sleet or hail
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

27. 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?

28. = body of air with a certain temperature and moisture level
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

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

30. Occluded Front:
Stationary Front:

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

33. 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

34. Pressure Systems

35. 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

36. Beaufort Wind Scale

37. Global Winds
Thousands of kilometers long; can cause weather to move in different directions
Jet stream, prevailing westerlies, doldrums, horse latitudes, trade winds
Big Winds Blowin’ Worksheet & Science Saurus Section 217

38. Global Winds Caused by the temperature difference in different regions
Hot Tropical Regions—causes air to rise
Cold polar Regions—causes air to sink

39. Global Winds Also affected by Earth’s Spin
Coriolis Effect = causes winds to curve to the right in the N. Hemisphere; to the left in the S. Hemisphere

40. Big Winds Blowin’ Worksheet

41. 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?

42. 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

43. 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

44. 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

45. 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

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

47. 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:

48. Rainbow by Brainpop

49. 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

51. Science Saurus Sections 203-204-205-206

52. Advanced Weather by Brainpop
Violent Weather

53. Types of Storms

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

55. 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

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

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

59. 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 (+)

60. Thunder is the shock wave caused by the explosive expansion of heated air
Sound about 1100 ft/sec in air
5,280 ft in one mile
Distance from you to lightning = number of seconds between seeing the flash and hearing the thunder divided by 5.
(5,280 ft / 1100 ft/sec = 5 seconds)

61. Types of Lightning Streak or bolt Single or branched lines of light
Common in Puget Sound area

62. Sheet a. shapeless flash over wide area
b. is cloud-to-cloud bolt hidden by the clouds
c. common in Puget Sound area

63. Other types of lightning
a. heat, ribbon, beaded (types of bolt)
b. ball (only other shape lightning can have)

64. Safety rules for lightning storms
Stay indoors
Stay away from anything that conducts electricity (stove, sink, telephone, TV)
Get out of the water and off of small boats
Stay away from open doors, windows, fireplaces
Stay in your car (very safe place to be)
Don’t stand under lone trees or in open places
Avoid hilltops
If your hair stands on end, or your skin tingles, drop to the ground but try to keep as little contact with the ground as possible

65. Stories of people hit by lightning
Lightning Strikes
(17 minutes)
Stories of people hit by lightning

66. Tornado (a.k.a twister, cyclone)
Counterclockwise column of rotating air extending from cumulonimbus cloud
Per square foot, is the most destructive atmospheric event
Rated by wind speed (F1 to F5)
“Tornado season” = April, May, June
Tornadoes that form over water are called “waterspouts”

67. Behavior of a tornado is unpredictable Typical tornado will:
1. Occur between 3-7 pm
2. Travel 4 miles
3. Be m wide
4. Travel mi/hour
5. Have wind speeds up to 300 mi/hr
6. Produce extremely low pressure
7. Be dark due to debris picked up
Tornado by Brainpop

68. Move away at a right angle
Safety Rules
Rule #1: Take immediate action!
Move away from tornado’s path
Tornado’s path
Move away at a right angle

69. Lie flat in nearest ditch, etc. At home a. open windows, doors
b. seek shelter in basement or under heavy table in middle of house
On the trail of a tornado

70. Tropical Cyclone Nicknames 1. Atlantic: hurricane
2. SE Asia, Japan: typhoon
3. Australia: willy-willy
4. Indian Ocean: cyclone

71. Tropical Cyclone Rated by wind speed (category 1 to 5)
Starts and grows over warm ocean water
Composed of bands of thunderstorms spiraling counterclockwise around a low pressure center

72. Characteristics Several hundred miles wide Last many days (even weeks)
Winds from mi/hr
Contains an “eye”
Small region of low pressure
Surrounded by highest winds
Calm, peaceful, sunny weather
Last for about 1 hour as hurricane passes by
Hurricances by Brainpop

73. Safety Rules Prepare for high winds
Prepare for flooding (greatest source of damage)
Up to 20 in. of rain
Flooding by coastal water
3. Prepare for thunderstorms
4. Have on hand stored food, water, blankets, candles, matches, radio, etc.
5. Seek shelter
Hurricanes Clip