Unit 6: Atmospheric Science

1
Unit 6 Atmospheric Science

• Topic
• Earths Energy

2
Solar Electromagnetic Spectrum

• The primary source of energy for the Earth is
  solar radiation. (energy received from the sun)
• Solar radiation has its greatest intensity at the
  visible wavelength
• What page of the reference table is this found on?

3

• The strength of electromagnetic energy depends on
  the wavelength of the energy.
• The shorter the wavelength the more intense it
  is, the longer the weaker it is

4
Page 14 of the ESRT
5
What color in the visible spectrum is the most
powerful?
6
Energy Transfer

• Energy has to be able to transfer in the
  atmosphere or interact between the earths
  surface and the air in order to produce weather
• There are three ways to transfer energy in the
  atmosphere
• CONVECTION, CONDUCTION, RADIATION

7
All Forms of heat transfer
8

CONVECTION

• Only occurs in liquid and gasses
• Need a heat source which will cause the material
  to rise (less dense), cool and spread, then fall
  because it is more dense

9
Cools and expands (air is less dense)
Warm air rising
Less dense
Cold air falling
More dense
10
Planetary Convection
11
(No Transcript)
12
Conduction..

• Transfer of energy from molecule to molecule
• Most effective in solids

13
Mommy My feet are Burning!!!
14
Radiation

• Travels in waves
• It is the only form of energy transfer that does
  not require a medium to travel through
• This form of energy can travel through space

15
Radiation
This energy will travel in waves and the two
major things that we get with this is ultraviolet
energy and visible energy.
16
(No Transcript)
17
Unit 6 Atmospheric Science

• How does the suns energy interact with the
  ground?

18
Reflection

• What type of surface will cause this?

19
Scattering
When does this happen?
20
Refraction
21
Absorption
What type of surface is the best for absorption?
The Worst?
22
Terrestrial Radiation
If youre a good absorberyou are also a good
radiator. What does this mean?
23
Dew Point and Humidity

• The dew point is the air temperature at which
  condensation occurs
• Condensation is the process of water vapor
  turning into liquid water.
• The humidity is the percentage of water vapor in
  a parcel of air
• A parcel is just a portion/section of the air

24
How does dew form?

• It is a relationship between the amount of
  humidity and the temperature

25
Time- 2 Pm Temp- 80
Time- 7AM Temp.- 55
Time- 6 PM Temp- 68
Time- 8 PM Temp- 55
Dew droplets
D.P.- 55 Humidity- 45
D.P.- 55 Humidity- 70
Dew Point- 55 Humidity- 100
D.P.- 55 Humidity-100
26
Dew Point versus Humidity

• As you go higher in the sky the temperature cools
  to the dew point and condensation occursCLOUDS

27
Cloud Formation
Expands as condenses due to thinner air
Dew Point breached
Rising air cools to the dew point
28
Humidity

• The Relative Humidity is the percentage of water
  vapor in a parcel of air.
• According to the previous diagrams, what time of
  day is the relative humidity the highest?
• Early morning and late evening
• Is there any difference between 80 humidity in
  the summer and winter?

29
Mr. Bacciles Demonstration

• When the air is heated it expands. Therefore,
  there is more room to fit water vapor. So 80
  humidity in the summer is actually much more
  water vapor in the air.

summer
winter
30
(No Transcript)
31
Figuring Dew Point and Humidity

• A sling-psychrometer is the tool used for
  figuring this
• There is a wet-bulb and a dry-bulb on the tool
• The wet-bulb measures the amount of moisture in
  the air.
• How does this work?

32
The Wet-bulb

• The same reason why you feel cool after swimming
  in the summer
• If the air is dry, then there is a lot of room
  for water vapor in the air.
• Therefore, the water on your skin will evaporate
  quickly into the air
• Evaporation is cools its surroundings, therefore
  your skin feels colder

33

• Clear Skies very little moisture in the air
  more room in the air for evaporation cooler
  skin (wet-bulb)
• This will cause a big difference between the
  wet-bulb and dry-bulb

• Cloudy Skies lots of moisture in the air less
  room in the air for evaporation less change in
  temp. (wet-bulb)
• This will cause a Small difference between the
  wet-bulb and dry-bulb

34
The Wet-Bulb cont.

• The wet-bulb works the same way. When you spin
  it, the dry bulb reads the air temperature and
  the wet-bulb reads the moisture
• If the air is dry, there will be a big difference
  between the two temperatures
• If the air is very moist, then both will be
  similar

35
(No Transcript)
36
Using the E.S.R.T.

• If the dry-bulb temperature is 20 degrees and the
  wet-bulb is 15 degrees, what is the dew point and
  humidity.
• First take difference between the wet-bulb and
  dry bulb 5 degrees
• Now, use the difference number 5 and the dry bulb
  temperature 20

37
Calculating Dew Point and Humidity (E.S.R.T)

• What is the Dew Point and humidity if the air
  temperature (dry bulb), is 14 degrees and the wet
  bulb is 9 degrees?
• If the humidity is 60 and the air temperature is
  22 degrees, what is the dew point?

38
Unit 6 Meteorology

• Topics
• 1. Latent Heat
• 2. Barametric Pressure
• 3. Weather Fronts
• 4. The synoptic Weather Map

39
Latent Heat

• The 3 main phases of matter is solid, liquid and
  gas (ice, water, vapor)
• Latent heat is the amount of energy needed to
  change a phase of matter (ex. From solid to
  liquid)
• The heat energy needed to change a phase of
  matter is called calories.

40
Fusion

• Heat of Fusion (melting or freezing) is the
  process to solid changing to liquid or vice versa
  (ice to liquid water) takes how many calories?
• 80
• Heat of vaporization (condensing or evaporating)
  changing from liquid to gas or vise versa
  (liquid water to water vapor) takes how many
  calories?
• 540

41
(No Transcript)
42
Barometric Pressure

• This is the foundation of weather analysis.
• Measures the air pressure in either inches of
  mercury or in millibars
• What is 30.12 inches of mercury in millibars?
• There are two form of pressure systems HIGH (H)
  and LOW (L)

43
Pressure Continued

• High Pressure is also known as an anticyclone and
  Low Pressure is known as a cyclone
• It is important to remember that winds blow from
  regions of High to Low pressure

44
Temperature and Pressure

• Warm air tends to rise which place less pressure
  on the ground and cold air tends to sink which
  places more pressure on the ground
• There warm temperatures are associated with LOW
  pressure and cooler temperatures with HIGH
  pressure

45
Warm/Moist Air Rising
Cold/Dry air sinking
High
High
Low
Surface winds blow from High to Low pressure
46
Energy Transfer Convection
Describe how this happens. Describe how
convection produces clouds. Describe how
convection produces High and Low Pressure.
Describe how convection produces surface winds
47
Moisture and Pressure

• Moist air is less dense and will rise less
  pressure
• Dry air is more dense and will sink more
  pressure
• Moist air is less dense because it contains
  hydrogen (which is less dense than oxygen or
  nitrogen)

48
Low Pressure versus High Pressure

• Therefore, what type of weather is associated
  with Low Pressure?
• Warm and moist
• High Pressure?
• Cool and dry

49
Winds and Pressure

• Wind blows from High to Low pressure.
• What creates strong winds?
• When there is a large change in pressure over a
  short distance.
• Isobars are lines that connect equal points of
  pressure.
• So when the lines are close strong winds

50
(No Transcript)
51
Anticyclone-High Pressure versus Low
Pressure-Cyclone
What direction does the air move within
each? What are the lines (circles) called? On a
weather map, how do you know where the wind speed
is the greatest?
52
(No Transcript)
53
High Versus Low Pressure
54
Weather map analysis...
55
Weather Fronts

• Certain types of weather fronts are associated
  with pressure systems
• Normally cold fronts are associated with high
  pressure
• Warm fronts are associates with low pressure

56
Where does Precipitation Occur?

• A long the leading edge of a front.
• Clouds form as a result of convection
• Warm air rises, cools and expands into clouds
• When two fronts collide, the warm, moist air is
  forced up faster, causing large clouds and a
  chance of precipitation to form.

57
Precipitation on a cold front

• The cold air meets the warm air
• The cold air stays near the ground (more dense)
  and forces the warm air up, causing it to cool
  and expand into clouds

58
Precipitation along fronts
Where does the precipitation along the fronts
occur? How is the precipitation along a cold
front different than a warm front? Why
59
Precipitation along other fronts
60
Draw a profile along line A--B.
B
A
61
The Cumulonimbus Cloud
62
(No Transcript)
63
Verbal Quizlets review
64
A sample station model
996
55
50
65
Station Model Information

• No labels should be on any of the numbers when
  sketching a station model
• The only number that changes is the pressure
  number. (has to be in millibars)
• If the number is gt500 you place a 9 in front, if
  it is lt500 you place a 10 in front of it.
  Finally place a decimal between the last two
  intergers

66
Practice

• Abbreviate
• 1004.2
• 042
• 998.4
• 984

• Lengthen
• 769
• 976.9
• 001
• 1000.1
• 452
• 1045.2

67
Sketch a station model

• Temp 76 degrees
• Cloud cover 25
• Wind Direction ne
• Wind Speed 35 knots
• Dew Point 70 degrees
• Present Weather haze
• Pressure 989.4 mb

68
Label the Air Masses over the source regions
69
Draw in the mT, cT, mP and cP Air Masses
What are 2 characteristics of an air mass? Which
air mass would be associated with High pressure?
How about Low? What gives each air mass its
characteristics?
70
Hurricane Movement
Label the highs and lows and direction of wind
movement
71
Sketch the typical track of a hurricane across
the Atlantic
What causes the hurricane to deflect to the
Northeast near Florida?
72
(No Transcript)
73
(No Transcript)
74
(No Transcript)
75
(No Transcript)
76
Storm Surge
77
(No Transcript)
78
(No Transcript)
79
Tornado animation 1
80
Hail Formation
81
(No Transcript)
82
(No Transcript)