Transcript Earth’s Atmosphere - Wyalusing Area School District

Earth’s Atmosphere
What newsworthy weather
events have you noticed in the
media?
Weatherbug
• http://achieve.weatherbug.com/Home.aspx#
target1
• http://www.wnep.com/weather/regionaldop
pleriiradar/
Can you describe what you
see in this picture?
In this chapter you will learn about Earth’s
atmosphere, and the gases that support life.
Size of the Earth
• 1. Diameter = from the north pole to the
south pole it’s ~ 7916 miles
• 2. Circumference ~ 24,901 miles
• Equator- imaginary line that divides the
earth into hemisphere’s (north and south)
Tell the person next to you
what the 3 most important
features of earth
• 1. land
lithosphere
• 2. air
atmosphere
• 3. water
hydrosphere
Viking---astronomy connection
5-2 Development of Earths
atmosphere
Past Atmosphere
4 billion yrs ago
Methane
Ammonia
Water
Atmosphere at 3.8 billion yrs.
old
New gases
Methane
water
water
water
water
Water
H20
H
0
0
H
H
0
0
Ozone= 3 oxygen atoms
combined together to form a
protective layer
• Due to the ozone
• Blue-green bacteria
started to become
more abundant
• used sunlight, carbon
dioxide (co2) and
water to make food,
their byproduct was
oxygen
Present Atmosphere
5-3 Layers of the Atmosphere
What do mountain climbs have to carry as
they climb higher into the atmosphere?
La Rinconada,
Peru
Layers of the atmosphere
depends on temperature
changes
Troposphere
1.Almost all
weather occurs
here
56 mi.
31mi.
11 mi.
2. Extends 11miles
high
3. Jet stream
Convection currents
Currents of air are
produced as warm air
rises and cool air
replaces it.
Convection currents
• Movement of air caused by a difference in
temperature
• What’s really happening
• Cool dense air is sinking and warm, less dense
air is rising, causing a movement of air
Stratosphere
• Lower stratosphere temp. = extremely cold
Stratosphere
• Jet stream winds- strong eastward wind that
blows horizontally around the earth
Stratosphere
• Ozone layer
• Ozone ( a form of
oxygen, O3) reacts with
the uv light to warm the
air
Warm = 64° f
• Protects earth from
harmful uv radiation
Cold = -76°f
Stratosphere
Temperatures increase as you ascend.
Why?
The Ozone Layer absorbs ultraviolet rays,
giving off heat.
The Jet Stream
Video-15 min
• http://www.youtube.com/watch?v=L4CX7
GL_DPo
Mesosphere
coldest area of the
atmosphere
Shooting Starswhat are they?
• Protect us from
falling meteoroids
Meteoroids, meteors and
meteorites
• Meteoroid: An object in space no smaller than a speck
of dust and no larger than an asteroid. Most are thought
by scientists to be pieces of asteroids or comets.
• Meteor: The streak of light that forms when a
meteoroid burns while traveling at high speed through
Earth's atmosphere (a "shooting star" or "falling star").
• Meteorite: The remnants of a meteoroid that has
passed through the atmosphere and struck the Earth.
Thermosphere
• No definite Limit
• Very Hot? Why
• Nitrogen and Oxygen absorb a lot of UV
radiation and convert it to heat
• Thin air makes seeing objects in space more
easily.
Ionosphere
• Lower layer of the thermosphere
• Gas molecules are electrically charged
• Radio waves bounce back
• Brilliant light displays of aurora borealis occur
here
Exosphere
•Outer layer of thermosphere
•Satellites orbit Earth here
•Communicate long-distance telephone
and television signals
•Watch weather and weather patterns
Thermosphere
• No definite upper limit
Magnetosphere
• Extends above Earth
• Magnetic field that traps charged particles
from the sun
• Particles follow the lines of magnetic force
and bounce back and forth from one pole to
the other
• Sometimes breaking through into the
ionosphere to produce auroras
Aurora Borealis, Northern
Lights