Atmosphere Properties and Weather Notes Chapter 11-13.
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Transcript of Atmosphere Properties and Weather Notes Chapter 11-13.
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Atmosphere PropertiesAtmosphere Properties and Weather and Weather
Notes Chapter 11-13Notes Chapter 11-13
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Atmosphere
ClimateWeatherThin envelope of gases that surrounds the planet.
The state of the atmosphere at a given place and time
Weather conditions at a locality averaged over a specified time period
Meteorology Study of weather and climate
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LayersLayers of Atmosphere of Atmosphere
Exosphere (outer space)Exosphere (outer space)
Ozone Layer
Weather occursWeather occurs
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TroposphereTroposphere
Layer closest to our earthLayer closest to our earth Extends to a height of 8-15 kilometers (5-9 Extends to a height of 8-15 kilometers (5-9
miles)miles) Temperature ranges from Temperature ranges from (63° to -62°F) Weather occurs hereWeather occurs here A very large thunderstorm could extend into the A very large thunderstorm could extend into the
next layer of the atmospherenext layer of the atmosphere The air that we breathThe air that we breath Can contain air pollution, bad ozone, smogCan contain air pollution, bad ozone, smog
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StratosphereStratosphere
22ndnd layer of the atmopshere layer of the atmopshere Ozone layer (good ozone) that shields us Ozone layer (good ozone) that shields us
from harmful radiation from the sunfrom harmful radiation from the sun Temperature increase as you go up Temperature increase as you go up
through the atmospherethrough the atmosphere Temperature is (Temperature is (27°F).
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MesosphereMesosphere
33rdrd layer of the atmosphere layer of the atmosphere Meteorites burn up in this sectionMeteorites burn up in this section Coldest layerColdest layer
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ThermosphereThermosphere
44thth Layer of the atmopshere Layer of the atmopshere UV radiation is absorbedUV radiation is absorbed Shooting starsShooting stars Hottest layerHottest layer
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Natural Atmosphere ProcessesNatural Atmosphere ProcessesOzone Shield in the StratosphereOzone Shield in the Stratosphere
Ozone shield is needed to filter out the sun’s UV Ozone shield is needed to filter out the sun’s UV radiation. 95% filteredradiation. 95% filtered
The ozone shield protects humans from skin The ozone shield protects humans from skin cancer, sun burns, eye cataracts, and damage cancer, sun burns, eye cataracts, and damage to the immune systemto the immune system
Prevents the oxygen in the troposphere from Prevents the oxygen in the troposphere from being converted to photochemical ozonebeing converted to photochemical ozone
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What causes ozone depletion?What causes ozone depletion?CFCCFC
CFC—chlorofluorocarbonsCFC—chlorofluorocarbons CFC-11 trichlorofluormethane, CFC-12 dichlorodifluoromethane CFC-11 trichlorofluormethane, CFC-12 dichlorodifluoromethane
also known as freonsalso known as freons Odorless, colorless, nontoxic, nonreactive, nonflamable, Odorless, colorless, nontoxic, nonreactive, nonflamable,
noncorrosivenoncorrosive CheapCheap Used a coolants for air conditioners, refrigeratorsUsed a coolants for air conditioners, refrigerators Used as propellants in aerosol spray cansUsed as propellants in aerosol spray cans Cleaners for computer chipsCleaners for computer chips FumigantsFumigants
Insoluble to water so they remain in the atmosphereInsoluble to water so they remain in the atmosphere Each molecule can last 65-385 yearsEach molecule can last 65-385 years Each chlorine atom converts ozone to oxygenEach chlorine atom converts ozone to oxygen
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Anthropogenic effects on Anthropogenic effects on biogeochemical cyclesbiogeochemical cycles
Carbon cycleCarbon cycle Adding carbon dioxide by burning Adding carbon dioxide by burning fossil fuels, deforestationfossil fuels, deforestation
Nitrogen cycleNitrogen cycle Adding NOx by burning fossil Adding NOx by burning fossil fuels, fertilizers, acid depositionfuels, fertilizers, acid deposition
Sulfur cycleSulfur cycle Volcanoes, burning fossil fuels, Volcanoes, burning fossil fuels, making acid depositionmaking acid deposition
Toxic metals Toxic metals (arsenic, (arsenic, cadmium lead)cadmium lead)
Injecting those into the Injecting those into the atmosphereatmosphere
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Nitrogen (78%) & Oxygen (21%) Nitrogen (78%) & Oxygen (21%) Carbon dioxide & others (trace amounts)Carbon dioxide & others (trace amounts)
Gases in AtmosphereGases in Atmosphere
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3 methods of energy transfer:3 methods of energy transfer:
1)1) RadiationRadiation= transfer of energy through = transfer of energy through space by visible light, UV light, and space by visible light, UV light, and electromagnetic waves electromagnetic waves EX: sunEX: sun
2)2) ConductionConduction= transfer of energy when = transfer of energy when molecules collide molecules collide EX: metalsEX: metals
3)3) ConvectionConvection= transfer of energy by flow of = transfer of energy by flow of a heated substance a heated substance EX: water, airEX: water, air
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Humidity vs. Relative HumidityHumidity vs. Relative Humidity
Humidity= amount of water vapor in the airHumidity= amount of water vapor in the air
Relative Humidity= ratio of water vapor in Relative Humidity= ratio of water vapor in the air relative to how much water vapor the air relative to how much water vapor the air can holdthe air can hold
0% very dry0% very dry 90% very wet (rain is near)90% very wet (rain is near)
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Relative Humidity• The relative humidity tells us how “full” the air is at the time of measurement.
• For example, 90% relative humidity means that at that moment the air is holding 90% of the maximum amount of water it could.
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Relative HumidityRelative Humidity
Measure of water vapor in the air.Measure of water vapor in the air. Instrument = Instrument = HygrometerHygrometer If air holds all the water vapor it can, it is at If air holds all the water vapor it can, it is at
100% RH and is said to be 100% RH and is said to be saturatedsaturated
Warm air can hold more water vapor.Warm air can hold more water vapor.
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Air MassesThere are two types of air masses:
1. Continental Polar air masses
2. Maritime Tropical air masses
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Coriolis EffectCoriolis Effect
http://www.classzone.com/books/earth_science/terc/content/visualizations/es1904/es1904page01.cfm Animation Animation
Particles are deflected in the Northern Particles are deflected in the Northern Hemisphere to the right and in the Hemisphere to the right and in the Southern Hemisphere to the left.Southern Hemisphere to the left.
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Trade WindsTrade Winds The sun warms the air and it rises to 20 to The sun warms the air and it rises to 20 to
30 degrees to the South and the North, 30 degrees to the South and the North, then is falls back downthen is falls back down
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Jet StreamJet Stream
The current of fast moving airThe current of fast moving air Usually moves from East to WestUsually moves from East to West
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Fronts
A front is the boundary separating air masses of different densities
Fronts extend both vertically and horizontally in the atmosphere
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Fronts: Five Types of Fronts1. Cold Front: The zone where cold air is replacing warmer air
• In U.S., cold fronts usually move from northwest to southeast
• Air gets drier after a cold front moves through
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Fronts: Five Types of Fronts2. Warm Front: The zone where warm air is replacing colder air
• In U.S., warm fronts usually move from southwest to northeast
• Air gets more humid after a warm front moves through
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Fronts: Five Types of Fronts3. Stationary Front: When either a cold or warm front stops moving
• When the front starts moving again it returns to either being a cold or warm front
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High and Low Pressure Areas
• High pressure causes air to sink
• Usually results in several days of clear sunny skies
• Air rises in low pressure areas and forms water droplets
• Usually results in rain and storms
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Temperature and ThermometerTemperature and Thermometer
Measurement of how rapid or slow a Measurement of how rapid or slow a molecule move aroundmolecule move around
Measured by a thermometerMeasured by a thermometer UnitsUnits
Fahrenheit (Fahrenheit (°F)°F) Celsius (Celsius (°C)°C) Kelvin (K)Kelvin (K)
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Wind Direction and SpeedWind Direction and Speed
Direction is measured Direction is measured with a “vane”with a “vane”
Speed is measured with Speed is measured with an “anemometer.”an “anemometer.”
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Pressure and BarometerPressure and Barometer
Air molecules push down Air molecules push down on objects—including us!on objects—including us!
Measured by Measured by BarometersBarometers DemonstrationDemonstration
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Doppler Radar EffectDoppler Radar Effect Doppler Effect is the movement of Doppler Effect is the movement of
frequencies going away or toward you as frequencies going away or toward you as the source movesthe source moves
Radar measures the amount of Radar measures the amount of precipitation in the airprecipitation in the air
Doppler RadarDoppler Radar
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Pressure-Temperature-Density Pressure-Temperature-Density RelationshipsRelationships
As Temperature , PressureAs Temperature , Pressure
As Temperature , PressureAs Temperature , Pressure
As Temperature, DensityAs Temperature, Density
**Temperature and Pressure are directly proportionate **Temperature and Pressure are directly proportionate (goes the same direction)(goes the same direction)
** Temperature and Density are inversely proportionate ** Temperature and Density are inversely proportionate (goes in the opposite direction)(goes in the opposite direction)
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What happens in the atmosphereWhat happens in the atmosphere
Most of the time, the temperature and Most of the time, the temperature and pressure decreases through the pressure decreases through the tropospheretroposphere
Sometimes….the atmosphere does not Sometimes….the atmosphere does not have perfect relationships between have perfect relationships between temperature, density, and pressure.temperature, density, and pressure.
Warm Air rises, cold air sinksWarm Air rises, cold air sinks
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Temperature InversionTemperature Inversion
When the cold air is on When the cold air is on top of the warm air. top of the warm air. The warm air can not The warm air can not rise to release rise to release pollution.pollution.
This can lead to smog This can lead to smog and pollution closer to and pollution closer to the earth’s surfacethe earth’s surface
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Dew Point and CondensationDew Point and Condensation
Temperature at which air must be cooled Temperature at which air must be cooled at constant pressure to reach saturationat constant pressure to reach saturation
Saturation= amount that the atmosphere Saturation= amount that the atmosphere can hold.can hold.
Higher the dew point then condensation Higher the dew point then condensation (changing gas to liquid) can occur and it (changing gas to liquid) can occur and it can rain.can rain.
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HeatHeat
Transfer of energyTransfer of energy
Hot ALWAYS travels into the ColdHot ALWAYS travels into the Cold
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Weather Station ModelWeather Station Model
Directions:
•Read the handout again to understand what each symbol means
•Use the chart to draw your own on in your lab book
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Weather MapsWeather Maps
From the weather maps, you are going to From the weather maps, you are going to answer the questions about the maps in answer the questions about the maps in your comp book.your comp book.
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Clouds Clouds Write this on your own paper for your notesWrite this on your own paper for your notes
Turn in your textbooks to page Turn in your textbooks to page 287287
Draw this chart on the screenDraw this chart on the screen
Using your textbook and table 11-Using your textbook and table 11-3, write what the description and 3, write what the description and draw a picture of the clouddraw a picture of the cloud
When you have finished see me to When you have finished see me to pick up your construction paper pick up your construction paper and cotton balls. You will and cotton balls. You will reconstruct the clouds out of the reconstruct the clouds out of the cotton balls. Please label each cotton balls. Please label each cloud.cloud.
After everyone builds the clouds After everyone builds the clouds we will go outside and observe we will go outside and observe themthem
Cloud NameCloud Name DescriptionDescription PicturePicture
CirrusCirrus
CumulusCumulus
StratusStratus
NimbusNimbus
CumulonimbusCumulonimbus
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Tornadoes vs. HurricanesTornadoes vs. Hurricanes
TornadoTornado Whirlwind of air on Whirlwind of air on
landland Measured by Fujita Measured by Fujita
scalescale F0-F5F0-F5
HurricanesHurricanes Whirlwind of air on Whirlwind of air on
waterwater Measured by Saffir Measured by Saffir
Simpson IndexSimpson Index 1-51-5
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Severe WeatherSevere Weather
ThunderstormsThunderstorms All contain lighting, cumulunimbus cloudsAll contain lighting, cumulunimbus clouds Single CellSingle Cell Multi CellMulti Cell Super Cell Super Cell violent tornados violent tornados
May produce flash floods/hail/tornadosMay produce flash floods/hail/tornados Downdrafts Downdrafts damaging winds near damaging winds near
surfacesurface
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TornadosTornados
Violently rotating column of Violently rotating column of air in contact with the air in contact with the ground ground
Rotating updraftRotating updraft is a key to is a key to the development tornado. the development tornado. Caused by wind shearCaused by wind shear
5mph
25 mph
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MesocycloneMesocyclone
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How does lightening form?How does lightening form? Air friction in the Air friction in the
cloudsclouds Separate + and – Separate + and –
create voltage create voltage channelchannel
Lightning kills Lightning kills more people than more people than tornados, tornados, hurricanes hurricanes
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What causes thunder?What causes thunder?
30,000 30,000 ooC air C air expandsexpands
““Explosion of Air”Explosion of Air” Light waves travel Light waves travel
faster than sound faster than sound waveswaves
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Weak Weak Strong Strong
No greater than 110 mph
110 mph – 200mph 200 mph +
Less than 2%
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Cyclones, Typhoons, Hurricanes???Cyclones, Typhoons, Hurricanes??? All the same thingAll the same thing
All need energy source All need energy source = warm tropical water= warm tropical water
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HurricanesHurricanes Tropical cyclones with winds that exceed Tropical cyclones with winds that exceed
64 knots (74 mi/hr) 64 knots (74 mi/hr) circulate counter-clockwise circulate counter-clockwise
Northern Hemisphere Northern Hemisphere Clockwise in the Clockwise in the
Southern Hemisphere Southern Hemisphere Water must be warmer than 81 FWater must be warmer than 81 F
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Stages of DevelopmentStages of Development
Depression Depression Storm Storm Hurricanes Hurricanes
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Extreme Weather Video ClipsExtreme Weather Video Clips
http://dsc.discovery.com/videos/wonders-of-http://dsc.discovery.com/videos/wonders-of-weather-extreme-weather.html (extreme weather-extreme-weather.html (extreme weather)weather)
http://dsc.discovery.com/videos/wonders-of-http://dsc.discovery.com/videos/wonders-of-weather-lightning-phenomena.html (lightning)weather-lightning-phenomena.html (lightning)
http://dsc.discovery.com/videos/storm-chasers-http://dsc.discovery.com/videos/storm-chasers-science-of-storm-chasing/ (storm chasers)science-of-storm-chasing/ (storm chasers)
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HurricanesHurricanes
http://planetgreen.discovery.com/videos/http://planetgreen.discovery.com/videos/focus-earth-hurricanes-and-climate-focus-earth-hurricanes-and-climate-change.html (climate and hurricanes)change.html (climate and hurricanes)
http://www.pbs.org/wgbh/nova/http://www.pbs.org/wgbh/nova/sciencenow/3204/02.html (hurricanes)--12 sciencenow/3204/02.html (hurricanes)--12 minmin