Atmosphere Properties *Copy the information in GREEN

Atmosphere ClimateWeather Thin envelope of gases that surrounds the planet. The state of the atmosphere at a given place and time Weather conditions at a locality averaged over a specified time period Meteorology Study of weather and climate

Layers of Atmosphere Exosphere (outer space) Ozone Layer Weather occurs Refer to foldable in your notebook!

Troposphere  Layer closest to our earth  Extends to a height of 8-15 kilometers (5-9 miles)  Temperature ranges from  Temperature ranges from (63° to -62°F)  Weather occurs here  A very large thunderstorm could extend into the next layer of the atmosphere  The air that we breathe  Can contain air pollution, bad ozone, smog

Stratosphere  2 nd layer of the atmopshere  Ozone layer (good ozone) that shields us from harmful radiation from the sun  Temperature increase as you go up through the atmosphere  Temperature is (  Temperature is (27°F).

Mesosphere  3 rd layer of the atmosphere  Meteorites burn up in this section  Coldest layer

Thermosphere  4 th Layer of the atmopshere  UV radiation is absorbed  Shooting stars  Hottest layer

 Nitrogen (78%) & Oxygen (21%)  Carbon dioxide & others (trace amounts) Gases in Atmosphere

Ozone Shield in the Stratosphere  needed to filter out the sun’s UV radiation. 95% filtered * page 275*  protects humans from skin cancer, sun burns, eye cataracts, and damage to the immune system  Prevents the oxygen in the troposphere from being converted to photochemical ozone*

Chloroflurocarbons AKA CFC’s is an organic compound that contains carbon, chlorine, and fluorine is an organic compound that contains carbon, chlorine, and fluorine produced as a volatile derivative of methane and ethane. produced as a volatile derivative of methane and ethane.  Insoluble to water so they remain in the atmosphere  developed in the 1930's as safe, non-toxic, non- flammable alternative to dangerous substances like ammonia  purposes of refrigeration and spray can propellants. Their usage grew enormously over the years.

Problem with CFC’s   Very little chlorine exists naturally in the atmosphere.   CFCs are introducing chlorine into the ozone layer.   UV radiation at this altitude breaks down CFCs, freeing the chlorine. Under the proper conditions, this chlorine has the potential to destroy large amounts of ozone.   This has been observed, especially over Antarctica. Levels of harmful UV radiation have increased.

What are we doing to help?   CFC’s are being replaced and monitored.   1978 The Montreal Protocol was adopted regarding CFC control

Aerosols   NASA definition: minute particles suspended in the atmosphere. Can be solid, gases or liquid.   Most are produced by natural processes such as erupting volcanoes, and some are from human industrial and agricultural activities   Light-colored aerosol particles reflect incoming energy from the sun (heat) in cloud-free air and dark particles can absorb it.   In short, aerosols can modify our climate.

Types of aerosols   Volcanic aerosol: sulfur dioxide (gas emitted) creates sulfur acid which reflects sunlight   Desert dust:dust is made minerals which absorb sunlight & scatter it. Because the dust particles absorb the sunlight, it warms the layer of the atmosphere where they reside. This warmer air can inhibit the formation of storm clouds. *WHAT WOULD PREVENTION OF STORM CLOUDS CAUSE?   Human-made aerosol: come from activities we do…increased since the industrial revolution.

Aerosols effecting our atmosphere   Evidence now exists that shows changes in stratospheric ozone concentrations which occur after major volcanic eruptions, like Mt. Pinatubo in 1991, where tons of volcanic aerosols are blown into the atmosphere (Fig. 1).

DRAW a simple diagram in your notebook!

The removal of Aerosols   It is believed that much of the removal of atmospheric aerosols occurs in the vicinity of large weather systems and high altitude jet streams, where the stratosphere and the lower atmosphere become intertwined and exchange air with each other.