Transcript The Atmosphere

The Atmosphere
By Raj Patel
Composition
• The Earth’s atmosphere is composed of 7
primary compounds: Nitrogen (78%), Oxygen
(21%), Water Vapor (0-4%), Carbon Dioxide,
Methane, Nitrous Oxide, Ozone (<<<1%).
• Nitrogen is the most pervasive while CO2 has
increased about 25% in the last 300 years.
• Some of these compounds contribute to
increased temperatures such as CO2,
Methane, N20, etc.
Structure (Layers)
• Troposphere -(0-11 km) above the surface. 75% of
atmosphere’s mass is in the troposphere.
• Stratosphere- Contains the Ozone Layer. Temperature
increases with altitude due to absorption of heat by
the ozone.
• Mesosphere-It is the coldest layer and temperatures
decrease with altitude. Meteors burn up in this layer.
• Thermosphere (Ionosphere)-Temp. increases with
height due to gamma rays, x-rays, and UV radiation.
Also Molecules are converted into ions which results in
the aurora borealis (Northern Lights).
Layers of the Atmosphere
• http://www.youtube.com/watch?v=0vcHBNM
w2h0
Weather and Climate
• Weather is caused by the movement or transfer
of heat energy which impacts the physical
properties of temperature, air pressure, humidity,
precipitation, available sunshine, and wind speed
and direction.
• Climate describes the total of all weather
occurring over a period of years in a given place.
• Regions nearer the equator receive much more
solar energy (and are warmer) than regions
nearer the poles.
Factors that Influence Climate
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Air Mass
Air Pressure
Albedo-reflectivity. (ocean water=low albedo, land =high albedo)
Altitude
Angle of Sunlight
Carbon Cycle and Greenhouse effect and Pollution
Clouds and Fronts
Distance to Oceans
Landmass distribution-different materials absorb varied amounts of heat
i.e. water has high specific heat
Latitude and Location
Humidity
Plate tectonics and Volcanoes
Wind Patterns
Human Activity
Coriolis Effect
• If not for the Earth’s rotation, global winds would
blow in straight north-south lines. What actually
happens is that global winds blow diagonally. The
Coriolis effect influences wind direction around
the world in this way: in the Northern
Hemisphere it curves winds to the right; in the
Southern Hemisphere it curves them left.
http://www.universetoday.com/73828/what-isthe-coriolis-effect/#ixzz2Pw6ikLVn
Coriolis Effect
Rain Shadow Effect
• A rain shadow is a dry area on the
mountainside facing away from the direction
of the wind. The mountains block the passage
of rain-producing weather systems, casting a
“shadow” of dryness behind them.
El Nino
• Occurs when the air pressure patterns in the South Pacific
reverse direction, the trade winds decrease in strength and
can reverse direction. The result is that the normal flow of
water away from S. America decreases and ocean water piles
up off S.A.
• This pushes the thermocline (the region in
a thermally stratified body of water which separates warmer
surface water from cold deep water and in which temperature
decreases rapidly with depth) deeper and decreases the
upwelling of nutrient rich deep water (leads to extensive fish
kills).
• The Sea Surface temperature increases in the eastern Pacific.
• Rainfall common in Central Pacific, while dearth in Western
Pacific.
La Nina
• Trade winds blow east across the tropical Pacific
are stronger than normal leading to increased
upwelling and Cooler-than-normal sea surface
temperatures. It brings nearly the opposite
effects of El Nino to the U.S., with wetter
conditions across the Pacific northwest and dryer
and warmer conditions in southern states.
• Responsible for heavier than normal monsoons in
Southeast Asia and increase in hurricanes that
occur during the same period.
• http://library.thinkquest.org/5818/elnino.html
Natural Disasters
• Hurricanes-most sever weather phenomenon
that begins over warm oceans where trade winds
converge. Also comprised of convective storms.
• Tornadoes- swirling masses of air with wind
speeds close to 300 mph. Like hurricanes, the
center is an area of low pressure.
• Monsoons-strong, violent winds that change
direction with the season. Monsoons blow from
the land toward the sea in winter and from the
sea toward land in the summer. (blow from cold
to warm regions).
The Zone of the atmosphere in which
weather occurs is known as the
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A) ionosphere
B) mesosphere
C) Troposphere
D) Thermosphere
E)Stratosphere
The ozone layer exists primarily in
what section of the atmosphere?
A)
B)
C)
D)
E)
Troposphere
Stratosphere
Mesosphere
Thermosphere
Ionsosphere
The Surface with lowest albedo is
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Snow
Ocean water
Forest
Desert
Black topsoil
Along the Equator
A)
B)
C)
D)
E)
warm, moist air rises
Warm, moist air descends
Warm, dry air descends
Cool, dry air descends
Cool, moist air descends
A)
B)
C)
D)
E)
What process is responsible for
dryness on one side of a
mountainside?
El Nino
La Nina
Rain Shadow Effect
Coriolis Effect
Greenhouse Effect
Answers
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Troposphere
Stratosphere
Black topsoil
Warm, moist air rises
Rain shadow Effect