Ch. 1Sec. 3

Layers of the Atmosphere

Layers of the atmosphere are classified by changes in temp.

troposphere

• lowest layer• from 0 12 km

• we live in it

Weather occurs in the troposphere.

stratosphere• 12 50 km

• absorbs UV radiation

• ozone layer

• weather balloons

mesosphere• 50 80 km

• meteors burn up

• coldest part of atmosphere

Most meteoroids burn up in the mesosphere.

thermosphere• outermost layer• 80 km to outer space• no definite outer limit• divided into 2 layers:

1. ionospherelower layeraurora borealis

AURORA BOREALIS

Communication satellites orbit Communication satellites orbit Earth in the exosphere.Earth in the exosphere.

2. exosphere= outer layer

satellite

AURORA BOREALIS

thermosphere(ionosphere)

stratosphere•absorbs UV

radiation

troposphere•lowest layer

•we live in it

mesosphere•meteors burn up

stratosphere•ozone layer

mesosphere

•coldest part of atmosphere

thermosphere(exosphere)= outer layer

satellite

Weather occurs in the troposphere.

Communication satellites orbit Communication satellites orbit Earth in the Earth in the exosphere exosphere

(thermosphere).(thermosphere).