Transcript Courtesy LPI/NASA

Modern Atmosphere and Air
Pollution
Sunrise from space over the South China Sea. An astronaut would see something like this; clearly
defined bands of color through the atmosphere as the sun rises. High-peaking cumulus clouds,
topping out in anvil-head cirrus can be seen as black shadows against the sunlit horizon. The
brightness of the colors in the atmosphere in this photograph is due to the amount of dust in the
atmosphere. More dust is found in near the equator. There are various sources for such upper leve
dust. Many dust storms in Africa and ash clouds from major volcanic eruptions are two reasons.
Earth viewed from the Moon
Why is the Sky Blue?
The atmosphere protects Earth
Surface
Cosmic rays are very
high-energy
particles, mainly
originating outside
the Solar System.
They may produce
showers of
secondary particles
that penetrate and
impact the Earth's
atmosphere and
sometimes even
reach the surface.
Composed primarily
of high-energy
protons and atomic
nuclei, they are of
mysterious origin.
Pressure vs. Altitude
Air density vs. Altitude
 h 
 ( h )   0 exp 

 H0 
 0  1.2 kg/m
H 0  7.99 km
3
Atmospheric Criterion
Homosphere 0-80
km
The gases are mixed
nearly uniformly.
Heterosphere
The gases are not
evenly mixed.
Stable Components of the
Atmosphere
Atmospheric Temperature
Criterion
• Troposphere – the region of principal weather
activity, 90% of the atmosphere. The upper
limit defined by temperature of -57C.
• The upper layer is called tropopause, 18 km at
the equator and 12 km at middle latitude; 8
km at the poles.
The temperature profile of the
troposphere
• Normal lapse rate ,
decrease of 6.4C per km
and it is only an average;
Standard Atomosphere
• The actual lapse rate is
called Environmental
lapse rate
Stratosphere
• Extends from 18 to 50 km from the Earth’s
surface.
• Temperatures increase with altitude up to 0C
at 50 km
• The stratosphere is layered in temperature
because ozone (O3) here absorbs high energy
UVB and UVC energy waves from the Sun and
is broken down into atomic oxygen (O) and
diatomic oxygen (O2).
Stratosphere
Mesosphere
• Between 50 to 80 km
• The upper limit the
mesopause is the coldest
portion of the atmosphere
-90C
• This is due to decreasing
solar heating
Thermosphere
• Temperatures are rise sharply in the
mesosphere
• Thermospheric temperatures increase with
altitude due to absorption of highly
energetic solar radiation.
• Radiation causes the atmosphere particles in
this layer to become electrically charged (the
Ionosphere
Atmospheric Function Criterion
• The Ionosphere absorbs
cosmic rays, gamma rays, Xrays and shorter ultra violet
wavelengths, changing
atoms to positively charged
ions
• Extends from 85 to 600 km
Ionosphere and broadcast
http://www.windows2universe.org/earth/Atmosphere/ionosphere.html
Profile of the Atmosphere
Aurora Borealis
These two photos show the aurora borealis (Northern Lights) over Alaska
in March 2001. The green color of this aurora tells us something about it.
The green glow comes from oxygen atoms in Earth's upper atmosphere.
Images courtesy of Jan Curtis.
Ozonosphere
• The portion of the stratosphere that contains t
an increase level of Ozone.
• Ozone is a highly reactive oxygen and absovs
UV 100-300 nm and reradiates this energy in
infrared radiation.
• Today it is in situation of continues change
• ClO+O3 --->Cl+2O2
• Cl+O3 --->Cl0+O2
Chemical evidence of ozone damage
by humans
Vertical profile of the temperature
Space Diving
The big jump in History
Felix Baumgartner
http://www.youtube.com/watch?v=FHtvDA0W34I
Speed of the Jump