Transcript The Atmosphere

The
Atmosphere
Definition
The layer of gases
surrounding Earth;
composed mainly
of nitrogen and
oxygen
78% nitrogen
21% oxygen
1% other
Layers
http://www.fi.edu/wright/again/wings.avkids.com/wings.avkids.com/Book/Atmosphere/Images/atmos_layers.gif
Troposphere
• Where all plants and
animals live and
breathe
• Where weather takes
place
• 90% of the mass of
the atmosphere
• Thinnest layer
• Temp decreases with
altitude
http://atschool.eduweb.co.uk/kingworc/departments/geography/nottingham/atmosphere/pages/gfx/troposphere.jpg
Stratosphere
• Ozone in this layer stops many of the
sun's harmful rays from reaching the earth
• People can not breathe in this layer.
• Temperature increases as altitude
increases
• Keeps air warm and protects life on Earth
Ozone Layer
•Pale blue gas with a strong odor.
•90% of all ozone is found in the
stratosphere
•10% is found in the troposphere
•Ozone is extremely important
because it is the only gas that
absorbs ultraviolet radiation
from the Sun and protects the
surface of the Earth and people
from the damaging effects of UV
rays
http://ess.geology.ufl.edu/ess/Notes/090-Ozone_Depletion/depl2.jpg
Mesosphere
• Meso = middle between strato and thermo
• Windstorms reach speeds of 320 km/h
• Temp decreases with altitude
– coldest layer (-93 degrees C)
• This is where we see "falling stars" –
meteors burning up as they fall to Earth
Ionosphere
• An extension or a part of the
upper mesosphere and lower
thermosphere. So technically,
the ionosphere is not another
atmospheric layer.
• Composed of electrically
charged particles
• Auroras take place in this
area
• Radio waves are reflected by
this layer
Thermosphere
• Layer of the atmosphere which is first
exposed to the Sun's radiation
• Temperatures are very high, but doesn’t
feel hot because particles don’t transfer
energy
• The air is very thin
Exosphere
• Highest layer of the atmosphere. The air is
very thin here
• Atoms and molecules escape into space
Let’s look at an animation:
http://earthguide.ucsd.edu/earthgu
ide/diagrams/atmosphere/index.ht
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