Transcript The Atmosphere The Atmosphere  Today, human activity is altering the quantities of some of these variable gases  CO2  CH4  N2O  O3 

The Atmosphere
The Atmosphere
 Today, human activity is altering the quantities of
some of these variable gases
 CO2
 CH4
 N2O
 O3
 CFCs
STRUCTURE AND SCIENCE OF THE
ATMOSPHERE
 The atmosphere consists
of four layers
 Troposphere –surface to
7 mi.
 Stratosphere 7-31 mi
contains the ozone layer
 Mesosphere 31-51 mi
 Thermosphere up to
300mi
STRUCTURE AND SCIENCE OF THE
ATMOSPHERE
 Normally, temperature decreases as altitude increases in the
troposphere, but sometimes a warm layer of air at mid-altitude will
cover a layer of cold, dense air below, producing a thermal inversion
 This inversion layer traps emissions that then accumulate .
 This air quality factor is prevalent in many cities.
STRUCTURE AND SCIENCE OF THE
ATMOSPHERE
 Energy from the sun
heats the planet’s surface
unequally because of
latitude differences and
the tilt of the Earth’s axis
 This causes air and ocean
circulation patterns that
ultimately produce the
seasons and influence
weather and climate
STRUCTURE AND SCIENCE OF THE
ATMOSPHERE
 Weather specifies
atmospheric conditions over
short time periods and
within relatively small
geographical areas.
 Driven in part by the




convective circulation of air
being heated near Earth’s
surface
Air picks up moisture and rises
Higher up it cools and
condenses forming clouds
Precipitation can result
Cooler drier air descends
beginning the cycle anew
STRUCTURE AND SCIENCE OF THE ATMOSPHERE
 Climate describes the pattern of atmospheric conditions
found across large geographic regions over long periods of
time, typically seasons, years, or millennia
STRUCTURE AND SCIENCE OF THE ATMOSPHERE
 Large-scale circulation
systems consisting of pairs
of convective cells produce
global climate patterns
 Hadley convective cells near
equator – intense solar
radiation results in warm air
rising and expanding and
ultimately releasing the
moisture that becomes the
heavy rainfall of the tropics
STRUCTURE AND SCIENCE OF THE
ATMOSPHERE
 Ferrel cells and polar
cells are similar but
less intense as the
radiant energy
decreases.