1. Weather & Climate
Intro to Weather Clip

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

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

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

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

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

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

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

9. 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

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

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

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

13. 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.

14. Clouds by Brainpop

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

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

17. The Water Cycle
Water Cycle by Brainpop

18. Water Cycle Advanced by Brainpop

19. 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)

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

22. = 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

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

24. Occluded Front:
Stationary Front:

25. 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

26. 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

27. Global Winds
Thousands of kilometers long; can cause weather to move in different directions
Jet stream, prevailing westerlies, doldrums, horse latitudes, trade winds

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

29. 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

30. 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

31. 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

32. 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