Atmosphere in Motion Chapter 12

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Transcript Atmosphere in Motion Chapter 12

Atmosphere in Motion
Chapter 12
By Amy Johnson
gases surrounding the Earth
– necessary for supporting life
– protects against harmful UV and X-ray
– absorbs and distributes warmth
Galileo Galilei
proved air must have weight and contain
– Weighed flask, injected air, and reweighed to
find flask with injected air weighed more
Air stores and releases heat, holds moisture,
and can exert pressure
Composition of Atmosphere
subject to the pull of gravity
– exerts pressure in all directions, therefore
cannot be felt
– weight is equal to water over 10 m deep
mixture of gases, liquid water, and
microscopic particles of solids and other
Gases of the Atmosphere
Nitrogen – most abundant (78%)
 Oxygen – necessary for human life (21%)
 Variety of other gases in trace amounts
– water vapor is critical to weather (up to 4%)
» Responsible for clouds and precipitation
– carbon dioxide allows plants to make food
» Absorbs heat and emits it back to warm Earth
Aerosols in the Atmosphere
solids, such as dust, salt, and pollens and
tiny droplets of acid
– dust comes from volcanoes and wind blowing
across the soil
– salt results from wind blowing over the ocean
– pollen is released by plants
– burning coal in power plants also creates
Layers of the Atmosphere
based on temperature changes that occur with altitude
Lower Layers
– Troposphere
– Stratosphere
Upper Layers
– Mesosphere
» Ionosphere
– Thermosphere
– Exosphere
closest to the Earth (about 10 km)
 contains about ¾ of Earth’s entire
atmosphere including clouds and weather
 about 50% of Sun’s energy passes through
 Earth’s surface heats by conduction
– the farther from the surface you get, the cooler
it becomes
above troposphere (10 km – 50 km)
 contains most of the ozone
– Absorbs ultraviolet radiation to warm area
» As you go up, you get warmer
– without ozone, the UV radiation would reach
Earth and cause health problems
Extends 50km – 85km above surface
 Contains very little ozone so temperature
drops to the lowest in atmosphere
part of mesosphere and thermosphere
 due to intense interaction with the sun’s
 reflects AM radio waves allowing longdistance communications possible
– static results when interaction between this
layer and radiation is too active
reaches 85km – 500km
 temperatures increase rapidly
 filters out harmful X-rays and gamma rays
from the Sun
outermost layer
 extends outward to where space begins
– no clear boundary to space
Earth’s Water
70% of Earth’s surface is water
 Stored throughout the land-oceanatmosphere system in three different states
– Solid – snow, ice, glaciers
– Liquid – oceans, lakes, rivers
– Gas – water vapor
Water Cycle