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Intro to Weather Clip
Weather
 Temporary behavior of atmosphere
(what’s going on at any certain time)
 Small geographic area
 Can change rapidly
Weather
--The study of weather is
meteorology
--Someone who studies weather is
called a meteorologist
Climate
 Long-term behavior of atmosphere
(100+ years)
 Large geographic area
 Very slow to change
POLAR
90o -60o latitude
Cool summers, cold year-round
Dry
TEMPERATE
60o-30o latitude
True Seasons
Variety of climate patterns
Moderate precipitation (rain/snow)
TROPICAL
30o - equator
No winter, warm year-round
High temp, rainfall, humidity
What Factors Affect Weather
& Climate?
1. The Sun
2. The Water Cycle
3. The Atmosphere
4. The Ocean
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
The Water Cycle
All the water on the planet is recycled in
this manner!
Parts of the Cycle
Evaporation—Water going
from a liquid to a gas (gains
energy from the sun)
Parts of the Cycle
*Transpiration—evaporation of water
from/out of plants. Locate this on the
diagram!
transpiration
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.
Parts of the Cycle
Precipitation—when water falls out the
atmosphere. Forms when the water
droplets in clouds become too heavy to
stay up.
Precipitation
Liquid water = rain
Frozen water = snow
or sleet or hail
The Water Cycle
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
Troposphere
Stratosphere
Mesosphere
Ionosphere
Exosphere
Thermosphere
Write in the
labels!
Ozone layer
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
Fronts
= places where
air masses meet
4 Types: Warm,
Cold, Occluded,
Stationary
Each kind can
bring different
kinds of weather
Occluded Front: Stationary Front:
Science Saurus 221/222
& Reading a Weather
Map Worksheet
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
Pressure Systems
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
Beaufort Wind Scale
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
Global Winds
Caused by the temperature
difference in different regions
 Hot Tropical Regions—causes air to
rise
 Cold polar Regions—causes air to
sink
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
Big Winds Blowin’ Worksheet
Winds by Brainpop
1. What does warm air do?
2. What do you call winds
that blow all the time in the
same part of the world?
3. What are jet streams?
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
http://itg1.meteor.wisc.edu/wxwise/relhum/rhac.html
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
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
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
Humidity by Brainpop
1. What single factor controls
humidity?
2. What temperature air can
hold the most water molecules?
3. What causes water to
evaporate into the
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:
Rainbow by Brainpop
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
http://earth.rice.edu/MTPE/hydro/hydrosphere/topics/Ocean_Atm_Circ_ElNin
http://www.wunderground.com/MAR/
Science Saurus Sections 203-204-205-206
Advanced Weather by
Brainpop
Violent Weather
Thunderstorms
Requires a mature cumulonimbus
cloud
Signs
a. Sudden reversal of wind
direction
b. Noticeable increase in wind
speed
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
Thunderstorms
Safety Rules
 Stay indoors
 Prepare for lightning, strong winds
 Listen on radio/TV for tornado
watch/warning
 Thunderstorms don’t last long
Lightning Storm
Cumulonimbus cloud becomes
electrically charged and ground below
has opposite charge
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 (+)
Thunder is the shock wave caused by the
explosive expansion of heated air
Sound travels @ 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.
Types of Lightning
Streak or bolt
a. Single or branched lines of light
b. Common in Puget Sound area
Sheet
a. shapeless flash over wide area
b. is cloud-to-cloud bolt hidden by the
clouds
c. common in Puget Sound area
Other types of lightning
a. heat, ribbon, beaded (types of bolt)
b. ball (only other shape lightning can
have)
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
Lightning Strikes
(17 minutes)
Stories of people hit by
lightning
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”
Behavior of a tornado is unpredictable
Typical tornado will:
1. Occur between 3-7 pm
2. Travel 4 miles
3. Be 300-400 m wide
4. Travel 25-40 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
Safety Rules
 Rule #1: Take immediate action!
 Move away from tornado’s path
Tornado’s path
Move away at a right angle
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
Tropical Cyclone
Nicknames
1. Atlantic: hurricane
2. SE Asia, Japan: typhoon
3. Australia: willy-willy
4. Indian Ocean: cyclone
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
Characteristics
 Several hundred miles wide
 Last many days (even weeks)
 Winds from 74-200 mi/hr
 Contains an “eye”
a. Small region of low pressure
b. Surrounded by highest winds
c. Calm, peaceful, sunny weather
d. Last for about 1 hour as hurricane passes
by
Hurricances by Brainpop
Safety Rules
 Prepare for high winds
 Prepare for flooding (greatest source
of damage)
a. Up to 20 in. of rain
b. 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
Weather.Climate.Notes.ppt

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Weather.Climate.Notes.ppt

  • 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? 1. The Sun 2. The Water Cycle 3. The Atmosphere 4. 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.
  • 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. Precipitation Liquid water = rain Frozen water = snow or sleet or hail
  • 18.
  • 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
  • 21.
  • 22.
  • 23.
  • 24. 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
  • 25. Fronts = places where air masses meet 4 Types: Warm, Cold, Occluded, Stationary Each kind can bring different kinds of weather
  • 27.
  • 28. Science Saurus 221/222 & Reading a Weather Map Worksheet
  • 29. 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
  • 31. 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
  • 33. 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
  • 34. Global Winds Caused by the temperature difference in different regions  Hot Tropical Regions—causes air to rise  Cold polar Regions—causes air to sink
  • 35. 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
  • 36. Big Winds Blowin’ Worksheet
  • 37. Winds by Brainpop 1. What does warm air do? 2. What do you call winds that blow all the time in the same part of the world? 3. What are jet streams?
  • 38. 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 http://itg1.meteor.wisc.edu/wxwise/relhum/rhac.html
  • 39. 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
  • 40. 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
  • 41. 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
  • 42. Humidity by Brainpop 1. What single factor controls humidity? 2. What temperature air can hold the most water molecules? 3. What causes water to evaporate into the
  • 43. 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:
  • 45. 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 http://earth.rice.edu/MTPE/hydro/hydrosphere/topics/Ocean_Atm_Circ_ElNin
  • 47. Science Saurus Sections 203-204-205-206
  • 49.
  • 50. Thunderstorms Requires a mature cumulonimbus cloud Signs a. Sudden reversal of wind direction b. Noticeable increase in wind speed
  • 51. 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 Thunderstorms
  • 52. Safety Rules  Stay indoors  Prepare for lightning, strong winds  Listen on radio/TV for tornado watch/warning  Thunderstorms don’t last long
  • 53. Lightning Storm Cumulonimbus cloud becomes electrically charged and ground below has opposite charge
  • 54.
  • 55. 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 (+)
  • 56. Thunder is the shock wave caused by the explosive expansion of heated air Sound travels @ 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.
  • 57. Types of Lightning Streak or bolt a. Single or branched lines of light b. Common in Puget Sound area
  • 58. Sheet a. shapeless flash over wide area b. is cloud-to-cloud bolt hidden by the clouds c. common in Puget Sound area
  • 59. Other types of lightning a. heat, ribbon, beaded (types of bolt) b. ball (only other shape lightning can have)
  • 60. 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
  • 61. Lightning Strikes (17 minutes) Stories of people hit by lightning
  • 62. 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”
  • 63. Behavior of a tornado is unpredictable Typical tornado will: 1. Occur between 3-7 pm 2. Travel 4 miles 3. Be 300-400 m wide 4. Travel 25-40 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
  • 64. Safety Rules  Rule #1: Take immediate action!  Move away from tornado’s path Tornado’s path Move away at a right angle
  • 65. 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
  • 66. Tropical Cyclone Nicknames 1. Atlantic: hurricane 2. SE Asia, Japan: typhoon 3. Australia: willy-willy 4. Indian Ocean: cyclone
  • 67. 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
  • 68. Characteristics  Several hundred miles wide  Last many days (even weeks)  Winds from 74-200 mi/hr  Contains an “eye” a. Small region of low pressure b. Surrounded by highest winds c. Calm, peaceful, sunny weather d. Last for about 1 hour as hurricane passes by Hurricances by Brainpop
  • 69. Safety Rules  Prepare for high winds  Prepare for flooding (greatest source of damage) a. Up to 20 in. of rain b. 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