1. Bell Work
In which layer of the atmosphere does most of the weather we see occur?
In which layer of the atmosphere is the Aurora produced?
The air is made up of predominantly what type of gas?

2. Atmosphere – Air Masses and Fronts

3. Which has more heat, a small cup of hot water (at 80⁰C) or a large tub of hot water (also at 80⁰C)?
Which object contains the most heat, a boiling pot of water (0.5kg, at 100⁰C) or a gigantic iceberg (109 kg, at 0⁰C)?

4. Energy Heat: energy transfer between molecules in motion
Temperature: a measure of the average heat energy of a substance
All molecular motion stops at -273⁰C

5. Amount of water vapor in the air
Humidity:
Amount of water vapor in the air
Relative humidity- amount of water vapor in air compared to what it can hold at that temp.
25% Relative Humidity
100% Relative Humidity

6. Dew Point The temperature at which a gas condenses into a liquid.
Depends on temp. & humidity

7. If Temperature
Then density
Increases
Decreases
Warm Air: rises → cools → its density increases → sinks
Cold Air: sinks → warms → its density decreases → rises

8. Air masses
Large uniform volume of air that is consistent in temp., density & humidity
Pushed around globe by winds

9. Name Description c Continental Dry m Maritime Humid E Equatorial Hot T
3. Take on the characteristics of area over which it forms:
Name
Description c
Continental
Dry m
Maritime
Humid E
Equatorial
Hot T
Tropical
Warm P
Polar
Cold A
Arctic
Very cold

10. cA mP cP mP mT cT mT

11. Bell Work Why does the temperature in the: Troposphere ↓ with height?
Stratosphere ↑ with height?
Mesosphere ↓ with height?
Thermosphere ↑ with height?

12. Movement of Air Masses
Travel with global wind patterns
In US move from west to east
Air masses change as they move
FRONT: an area where two air masses meet

13. A. Cold Front: Cold air mass runs into a warm air mass
Cold air forces warm mass to rise
Rising warm air cools → releases moisture
Symbol on a map:

15. Cold Front Weather A shift in wind direction Sudden drop in temp.
Increasing clouds
Heavy rains & thunder
Followed by clearing with colder, drier weather

16. B. Warm Front:
Warm air mass runs into a cold air mass
Warm air mass is pushed up
Moisture in warm air cools & condenses → leads to rain
Warm air slowly pushes away cold air
Symbol on a map:

18. Warm Front Weather Winds change slightly
Slow, steady increase in temp.
Continuous precipitation along front
Hotter weather follows front

19. Stationary Front Weather
C. Stationary Front:
Two air masses meet and neither advances
Symbol on map:
Stationary Front Weather
Continuous heavy precipitation along front
Frequent flooding

20. D. Occluded Front:
Cold air mass overtakes a warm front
Symbol on map:

21. Occluded Front Weather
Colder temperatures
Continuous heavy precipitation along front
Light rain continues after front passes

22. Bell Work What is the difference between heat and temperature?
1/27/16
What is the difference between heat and temperature?
How does temperature affect the movement of air?
Get the air masses and fronts worksheet out to review (do NOT turn in)
Get your notebooks out for the notebook quiz

23. A B C Bell Work What type of front is shown in A? How do you know?
1/28/16 A
Bell Work
What type of front is shown in A? How do you know?
What type of front is shown in B? How do you know?
Identify each of the front symbols shown in C. B C

24. Clouds
A collection of water droplets or ice crystals formed when water vapor condenses into condensation nuclei.

25. Cloud names:
Alto-: clouds at middle altitudes
Cirro-: clouds that form at high altitudes
Nimbo- or -nimbus: clouds likely to produce precipitation
Cumulo-: piled up clouds
Strato-: layered clouds

26. Stratus clouds:
Form in layers
Cover large areas
Nimbostratus clouds:
Dark stratus clouds
Produce continuous rain

27. Cumulus clouds:
Puffy, white clouds with flat bottoms
When small indicate fair weather
When large (Cumulonimbus) produce stormy weather

28. Cirrus Clouds:
Thin, feathery, white clouds
Found at high altitude
When they get thicker, a change in weather is coming

29. Fog: stratus cloud that formed close to ground
Contrails: clouds formed when water vapor condenses around particles in aircraft exhaust

30. Heat: energy transfer between moving molecules Heat energy can be transferred in 3 ways:
Radiation: transfer of energy through electromagnetic waves (e.g. the sun)

31. Conduction: transfer of heat energy through a solid object e. g
Conduction: transfer of heat energy through a solid object e.g. a blacksmith heating metal to change its shape

32. Convection: transfer of heat energy through movement of a liquid or gas
Water when it boils
Magma in Earth’s mantle
Ocean currents
Air in the atmosphere

33. Pressure:
Force applied perpendicular to an object
Atmospheric Pressure:
Force applied against a surface by the weight of the air above

34. Atmospheric Pressure Systems
High Pressure System:
Cool air moves in and sinks
Winds blow out away from high pressure
Isobars:
Lines of equal pressure

35. High Pressure System:
Surface winds spiral outward from center – blow clockwise in Northern hemisphere
Brings fair, dry weather

36. Low Pressure System:
Hot air rises leaving a void (empty space)
Winds blow in toward center of low pressure

37. Low Pressure System
Winds blow Counter-clockwise in Northern hemisphere
Bring clouds & precipitation

38. Cyclones:
Occur where a lower pressure area is surrounded by higher pressure areas
Air spirals towards center of low pressure
Marked by L on weather map
Bring clouds and rain or snow

39. Anticyclone:
A rotation of air around an area of high pressure
Air spins clockwise away from center of the high pressure
Marked by H on weather map
Brings fair weather

40. Bell Work
2/1/16
1. Read the article: “Auroras in the Night Sky” 2. Answer the questions on the ½ sheet of paper

41. Global Pressure Cells
Hadley Cell: Warm air at the equator rises, moves towards the poles, cools, sinks at ~30° north & south of equator then moves back towards equator.

42. Polar cell: Cold air at the poles sinks, moves away from pole, warms, rises at about 60°N or south and moves back toward poles

43. Ferrel cell:
Sinking cold air at convergence with the Hadley cell moves north
Warmer air is pushed up at convergence with the air coming from the Polar cell

44. Wind: movement of air caused by differences in air pressure
↑ pressure difference → ↑ wind speed
Temperature (heat energy) affects air pressure:
Warm air rises - ↓ pressure
Cold air sinks - ↑ pressure

45. Global Wind Systems: caused by
Pressure gradients in Cells
Coriolis Effect

46. Polar Easterlies:
winds blow EAST to WEST from the poles to 60⁰ N. & S. of equator

47. Westerlies:
Winds blow from 30° latitude WEST to EAST towards polar easterlies in both hemispheres

48. Trade Winds:
Winds blow from 30° latitude EAST to WEST towards the equator in both hemispheres

49. Jet streams
Narrow belts of high speed winds (up to 400 km/h) in the upper troposphere and lower stratosphere.

50. Doldrums: Located along the equator; no winds blow; rising air & low pressure
Horse Latitudes
weak winds at 30 N and 30 S of equator

51. Bell Work North Carolina is at latitude 35.5°N of the equator.
1. What wind belt blows over us?
2. From what direction do the winds blow?

52. Cold front: Rainfall can be torrential and wind speeds can be high
Cold front: Rainfall can be torrential and wind speeds can be high. Blue lines with triangles on one side represents cold fronts on weather maps. The direction the triangles point is the direction in which the cold front is moving.

53. Warm front: Brings a gradual increase in rainfall followed by clearing and warming after the front passes. Can bring prolonged rain. A red line with semi-circles on one side represents warm fronts. The side the semi-circles are on represents the direction the front travels.

54. Occluded front: Formed when a cold front overtakes a warm front
Occluded front: Formed when a cold front overtakes a warm front. Weather events depend on whether it is a warm or cold occlusion. An occluded front usually brings heavy precipitation and changing wind directions. A purple line with semi-circles and triangles both on the same side represents occluded fronts and shows the direction of travel

55. Stationary front: Indicates a non-moving boundary between two different air masses. These fronts have long continuous rainy periods that linger for extended periods in one area and move in waves. A semi-circle bordering one side and triangles along the opposite side represents that the front is not moving in any direction.