Transcript Earth`s Atmosphere

Earth’s Atmosphere
intro
Atmospheric Composition
Gas
%
Nitrogen
78%
Oxygen
21%
Argon
0.9%
Carbon Dioxide
0.04%
Other Gases, Dust and
Water Vapor
0.06%
Earth’s Unique Atmosphere
1. Magnetic Field: a layer of electrical charge that
protects Earth by deflecting solar winds and
cosmic rays
• The magnetic field is caused by the liquid metal
in earth’s outer core
Ozone Layer
2. Ozone Layer: a layer of ozone (Oз) molecules
that reflects UV radiation
Ozone Layer
• Good ozone: found in the stratosphere and
reflects harmful UV radiation
Ozone
• Bad Ozone: found in the troposphere and
causes air pollution and harms lung tissue
Ozone Depletion
• Ozone Depletion: Humans are releasing CFC
gases into the atmosphere that destroy ozone
molecules
CFC’s
• CFC’s: Chlorofluorocarbons: gases that break
up ozone molecules in earth’s atmosphere
New Regulations:
Montreal Protocol (1987):
Now products are made
with little or no CFC gases
to protect our ozone layer
Earth’s Unique Atmosphere
3. Greenhouse Effect: Greenhouse gases trap
heat inside Earth’s atmosphere and reflect
heat back to Earth’s surface
Greenhouse Gases
• Greenhouse gas: any gas that
traps heat inside Earth’s
atmosphere
• Examples of greenhouse gases
are:
– Carbon dioxide: CO₂
– Methane: CH ₄
– Water Vapor: H₂O
– Nitrous oxide: N₂O
– Sulfur Dioxide: SO₂
Carbon dioxide
• Carbon dioxide is a greenhouse gas that
scientists think could be contributing to
a change in earth’s climate
Layers of the Atmosphere
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Exosphere
Thermosphere
Mesosphere
Stratosphere
Troposphere
Exosphere
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300-6000 miles above earth’s surface
Temperature increases with altitude
This is the hottest layer = 2000 ⁰F
Mostly just hydrogen and helium from solar
winds here
• The beginning edge of space
Thermosphere
• 50-300 miles above earth’s
surface
• Temperature increases with
altitude
• The space shuttle, space station
and satellites orbit here
• Auroras form here
• Aurora: a light display caused by
energetic particles interacting
with earth’s magnetic field
Mesosphere
• 30-50 miles above earth’s
surface
• Temperature decreases with
altitude
• The coldest layer = -130 ⁰F
• Meteors burn up here
• Noctilucent clouds: clouds
made of ice crystals form in this
layer
Stratosphere
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6-30 miles above Earth’s surface
Temperature increases with altitude
Good ozone layer found here
Military planes and jets fly here
– “Military space”
• The Jet Stream is found here
• Weather balloons (radiosondes)
reach this layer
Troposphere
• 0-6 miles above earth’s surface
• Temperature decreases with
altitude
• Contains the most air molecules =
highest air pressure
• Bad ozone = pollution and lung
tissue damage
• Weather and clouds form here
• Commercial airplanes fly here
• The highest mountain = Mount
Everest (5.5 miles)
Earth’s Energy Budget
• earth's energy budget
• Solar radiation: energy coming from the sun
in the form of electromagnetic waves
Earth’s Energy Budget
• 6% of solar radiation is reflected by the
atmosphere
• 20% of solar radiation is reflected by the clouds
• 4% of solar radiation is reflected by the surface
• 19%of solar radiation is absorbed by the
atmosphere and clouds
• 51% of solar radiation is absorbed by the surface
Earth’s Energy Budget
• What happens to MOST of the incoming solar
radiation from the Sun?
??Critical Thinking Question??
• How would life on earth be different if the
atmosphere did not absorb or reflect any
incoming radiation from the sun?
Albedo
• Albedo: the amount of solar radiation
reflected off of an object
• How much radiation is reflected depends on
the color, texture, composition, volume and
state of matter of the object
Albedo
• High albedo: snow,
water, clouds
• Low albedo: soil, forest,
asphalt
Atmospheric Conduction
• Conduction: the transfer of heat through physical
touch
• Earth’s surface gets heated by solar radiation
• Then air molecules that touch earth’s surface get
heated through atmospheric conduction
Atmospheric Convection
• Convection: the transfer of heat through the
movement of a fluid
• Hot air rises and cold air sinks creating
atmospheric circulation and global wind
patterns
Three ways to transfer heat
• Conduction
• Convection
• radiation
Popcorn
Lizard on a Rock
• Exit Ticket:
• How is this lizard getting heat energy
transferred to it?
• Use the terms radiation, conduction and
convection in your answer and write in
complete sentences
Protect the Penguin Activity
• Radiation from the sun heats the lizard and
the rock.
• Conduction from the hot rock heats the lizard
• Convection from the warm air circulating
around the lizard heats the lizard