Download Chapter 4 - ftgms-Mock

4.1
Earth’s
Atmosphere
A. Atmosphere
 Thin layer of air that protects
the Earth’s surface from
extreme temperatures and
harmful UV (sun) rays
B. Theory
 Volcanoes produced nitrogen and
carbon dioxide, but little oxygen
 Simple organisms began producing
oxygen
 Oxygen formed the ozone layer
(03)
 Green plants and diverse life forms
developed
C. Composition
 Solids: dust, salt, pollen
 Liquids: water droplets, acid from
volcanoes
 Gases: Nitrogen……………………78%
Oxygen…………………….21%
Carbon Dioxide & Argon…1.0%
D. Current Troubles
 Humans are
adding pollutants
 Energy use
 Increase in CO2
 Global Warming
 Hole in the ozone
layer (Antarctica)
E. A Bright Future
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Wind Energy
Solar Energy
Bio-fuel
Efficient cars
Car-pooling
Recycling
Factory waste minimized
F. Atmospheric Pressure
 As Earth’s gravity pulls gases toward its
surface, weight presses down on the air
below
 Molecules nearest to surface- closer
together
 Greater air pressure at surface
 As altitude increases, pressure decreases
 Fewer molecules…harder to breathe
Foldable Directions
1. Take 3 pieces of computer paper.
2. Layer the 3 pieces about an 1 ½ apart.
3. Fold the bottom layers up so there is 6 tabs showing.
4. Label as follows:
Exosphere
Thermosphere
Mesosphere
Stratosphere
Troposphere
Earth’s Surface
Troposphere
 0 to 10 km
 Lowest layer
 Weather
 99% of atmosphere water vapor
 75% of atmosphere gases
Stratosphere
 10 to 50 km
 Ozone layer (O3)
 Jet pilots fly here to avoid storms
Mesosphere
 50 km to 85 km
 Shooting stars
 Contains part of the ionosphere
Thermosphere
 85 to 500 km
 Thickest layer
 Coldest temps.
 Highest temps (3600 F)
 Contains part of the ionosphere
Exosphere
 Stretches to 5500 miles
 No weather
 Warm temperatures
 Few air molecules
 Space shuttles
4.2
Energy Transfer in the
Atmosphere
What percent of the sun’s energy is
absorbed and reflected by the Earth?
 UV Rays Absorbed
– 50% absorbed by
Earth’s surface
– 15% absorbed by
the atmosphere
65%
*Refer to page 99 in
your textbook
 UV Rays Reflected
– 25% reflected by
clouds
– 6% reflected by the
atmosphere
– 4% reflected by
Earth’s surface
35%
Process
How is energy
transferred?
Radiation
Rays or waves
Conduction
Convection
Sun, x-rays, tanning bed
Contact
Sand-feet, spoon-pan
Flow of air molecules
Oven, air in room
Water in our Atmosphere
 Hydrosphere
– All water on earth
 Conservation
– Water is never
created or
destroyed
Why is Earth Suitable for Life?
Planet
Atmosphere
Venus
-gases are very dense
-atm. traps heat (too hot)
Mars
-atm. too thin to support life
(too cold)
Earth
-O2 / CO2 balance
-water cycle
-ozone protection
4.3 Air Movement
A. Wind
Movement of air from an
area of higher pressure to
an area of lower pressure
Warm Air
Cold Air
Low
High
Pressure Low
High
Density
Effects
-rises
-replaced by
cooler air
-sinks
-replaces
warm air
B. Weather is determined by:
1. Coriolis Effect- rotation of the Earth causes
moving air and water to appear to turn
right north of the equator and left south of
the equator
2. Cool Air replacing warm air
-this determines when and where planes
and ships travel
C. Jet Streams
 Narrow belts of strong winds that
blow near the top of the
troposphere
 Faster in the winter because the
difference between cold air and
warm air is greater
D. Convection Currents
Sea Breeze
Land Breeze
What happens? Land heats
Land cools
faster than water faster than water
Where?
Toward land
Toward sea
When?
day
night
E. Global Winds
Location
Description
Prevailing
Westerlies
30 degrees N. & S.
latitude (most of U.S.)
Earth’s rotation
deflects air to east
as it moves to poles
Doldrums
along the equator
heat causes air to
expand: zone of
low pressure
Trade Winds between 30 degrees N.
and 30 degrees S. of
equator
Polar
Easterlies
b/c of coriolis effect,
winds curve back to
equator
60 degrees to the N. and cold, dense air sinks
S. pole
& moves away from
poles