Atmosphere

What is the Atmosphere

• Thin layer of air that regulates global temperature, and filters out dangerous solar radiation.

• Looks like a thin halo of blue light around the earth.

Composition of the Atmosphere

• 78% is nitrogen (N2)

• 21% is oxygen (O2)

• 1% are trace gasses

nitrogen oxygentrace gasses

The Layers from Space to Earth

• Thermosphere

• Ionosphere

• Mesosphere

• Stratosphere

• Troposphere

TIM ST.• An easy way to remember the layers is to use the

mnemonic device TIM St.

• T hermo sphere• I ono sphere • M eso sphere• S trato sphere• T ropo sphere

Troposphere

• Almost all weather occurs in this layer

• Most clouds, wind, rain, snow are in this layer

• As you go higher in the Troposphere it gets cooler.

Temperature Inversions

• Hot air is usually closer to the earth because the sun heats the surface of the earth.

• Temperature inversions- when cool air gets trapped beneath hot air.

• This happens in Los Angeles and causes smog = smoke (from cars) + fog (moisture in air)

Stratosphere

• The layer of the atmosphere that extends upward from the troposphere to an altitude of 50 km.

• Contains the ozone layer

O3

(Found in the Stratosphere) Ozone• Ozone comes from the greek ozein “to smell”

• Ionizers make ozone from oxygen

O2 Oxygen O3 Ozone

Naturally the Sun’s Rays make ozone from oxygen

O2 Oxygen

O3 Ozone

Depletion of the Ozone Layer

• Occurring over Antarctica

Ozone Depletion

• Caused by some chemicals such as CFC’s

Who cares if the ozone is thinning?

• Ozone provides protection from solar radiation which can cause skin cancers.

Mesosphere

• The mesosphere is 50-80 km

• This is the coldest layer of the atmosphere -80°C

• Noctilucent or "night-shining" clouds (NLCs). Occur in the mesosphere

Ionosphere

• The area of the earths atmosphere where electrically charged IONS are found

• Used in radio communications

• Closer to earth during the day

• Farther from the earth at night

Auroras occur in the Ionosphere

Excited ions release light in the polar regions of the globe

Thermosphere

• The hottest layer of the atmosphere

• Thermo = heat

• This is where meteorites can burn up upon entry into the atmosphere.

The Greenhouse Effect

The causes of the greenhouse effect

• The burning of fossil fuels to produce carbon dioxide gas

• Any process that releases carbon dioxide into the atmosphere

Atmosphere Poster

• Label the Layers of the atmosphere

• Elevations of the layers

• Temperatures of the layers

• 2 interesting facts about the layers

• Draw the two interesting facts in the appropriate layers