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atmosphere characteristics.notebook September 15, 2010
Characteristics of the Atmosphere* The atmosphere is a mixture of gases that surrounds the Earth.* It contains oxygen and protects us from the sun's ultraviolet rays.* The atmosphere has 78% Nitrogen, 21% Oxygen, and 1% of other gases.* It is held around the Earth by gravity.* As altitude increases in the atmosphere, pressure decreases.The atmosphere exerts 14.7 lbs per square inch of pressure on us at sea level due to the force of gravity on the column of air above us. We don't notice it because we're used to it.
* The layers of the atmosphere are divided by altitude, temperature, and air pressure.
atmosphere characteristics.notebook September 15, 2010
The Atmosphere has four main layers: • Troposphere• Stratosphere• Mesosphere• Thermosphere
The Troposphere is the bottom layer, closest to the Earth's surface. • It goes from sea level (0km) to 12 km (7.5 miles) up.• The troposphere is where weather happens and where we live.• As altitude increases, temperature decreases. • 90% of the atmosphere's mass is found in the troposphere.• "Tropo" means turning, and the troposphere gets its name because
the gases in the troposphere are always turning.
atmosphere characteristics.notebook September 15, 2010
The Stratosphere is the second layer. • It goes from 12 km (7.5 miles) to 50 km (30 miles) high.• Temperature stays the same from 12 km to 20 km, then from 20 km to 50 km, temperature increases as altitude increases because of the ozone layer. • The ozone layer is the upper part of the stratosphere, and is important because it absorbs UV radiation from the sun. • "Strato" means layers, and the stratosphere gets its name because the gases in the stratosphere are in layers.
The Mesosphere is the third layer. • It goes from 50 km (30 miles) to 80 km (50 miles) up.• In the mesosphere, as altitude increases, temperature decreases. • The coldest temperatures are found in the mesosphere. It can be as cold as 93 degrees Celsius.• Not much is known about the mesosphere, but it gets its name because "meso" means middle.
atmosphere characteristics.notebook September 15, 2010
The Thermosphere is the top layer. • It goes from 80 km (50 miles) up, and doesn't really have an upper limit because it merges with space. • As altitude increases, temperature increases. The highest temperatures are in the thermosphere, but it doesn't feel hot. This is because even though the air particles in the thermosphere are moving very fast, creating high temperatures; there are so few they don't bump into each other often, which means there is not a lot of heat.• Radio waves bounce off the Ionosphere, in the bottom part of the thermosphere, and travel around the world.
• Auroras are colorful curtains of light seen from Earth near the poles. They are caused by charged particles from the Earth's magnetic field colliding with nitrogen and oxygen in the thermosphere.
The atmosphere is THe MoST!!
THermosphereMesosphere(ozone layer)StratosphereTroposphere
ExosphereThermosphere
MesosphereStratosphereTroposphereIonosphere
atmosphere characteristics.notebook September 15, 2010
Draw a web diagram (bubble map) for the layers of the atmosphere:
Atmosphere
Troposphere
MesosphereStratosphere
Thermosphere
a mixture of gasesheld around the Earthby gravity
78% Nitrogen, 21% Oxygen
as altitude increases,pressure decreases
provides oxygen andprotects us from the sun's UV rays
bottom layer012 km (07.5 miles)
2nd layer up1250 km (7.530 miles)third layer up5080 km (3050 miles)
top layerfrom 80 km (50 miles) up
as altitude increases, temperature decreases
has high temperatures, but doesn't feel hot
as altitude increases, temperature decreases coldest layer
down to 93o C
ozone layer makes temperatures increase
where weather happensand where we live
ozone layer protectsus from the sun's UV rays 90% of atmosphere's
mass is here"strato" means "layers"
"meso" means "middle"no upper limit
ionosphere and auroras found here
