This PowerPoint goes into details about weather and the tools Scientists use to forecast the weather.

1. Weather

2. What do we know about
weather?
How do people measure and predict
the weather?

3. Meteorologist
• A scientist who studies the weather
• What kind of tools do they use?

4. Thermometer
• Used to measure temperature
• measures the kinetic energy of air
molecules
• Fahrenheit & Celsius thermometers

5. Anemometer
• Measures wind speed
• a system of gears converts the number of
turns per minute into wind speed

6. Hygrometer
• Measures humidity
• the moisture in the air

7. Weather Vane
• Measures wind direction
• changes in wind usually lead to change in
weather

8. Barometer
• Measures air pressure
• high pressure = clear cool skies
• low pressure = cloudy skies, moist air
• extreme low pressure = stormy weather

9. Cloud Conditions
• Observing clouds can tell a lot about the
weather

10. Cumulus
• White & puffy
• fair weather

11. Cirrus
• High in the sky
• white
• thin & wispy
• fair weather

12. Stratus
• Low in the sky
• thick & gray
• usually bring rain

13. Cumulonimbus
• Tower high into the sky
• gray to black
• Thunderstorms, hail, tornadoes
• anvil shaped

14. How can rising air pressure lead
to a prediction about weather?

15. Air Mass
• A large body of air that has the same
temperature and humidity throughout
• take on the characteristics of the region over
which they form
• 4 types in the the USA

16. Air Masses
– Categorized by moisture content and temperature
– Moisture categories: m = maritime (wet) and c =
continental (dry)
– Temperature categories: P (polar; cold), T
(Tropical; warm)

18. Continental Polar
• Cool dry weather

19. Continental Tropical
• Hot dry weather

20. Maritime polar
• Cool humid weather

21. Maritime Tropical
• Warm wet weather

22. Front
• Border where two air masses meet
• most weather changes occur along a front
• cold front = cold air mass moves under a
warm air mass creating cumulonimbus
clouds
• warm front = a warm air mass moves over a
cold air mass forming stratus clouds

23. What kind of air mass causes hot
humid weather?

24. Climate
• The regular weather pattern for a region
• precipitation & temperature determine
climate
• seasonal patterns
• all patterns are driven by the sun
• proximity to the equator determines
temperature patterns

25. ?????
• What is the cause of the seasons?
• What are two major factors of climate?
• What kind of climate would you find near
the equator?
• What kind of climate would you find at the
poles?