The layer lying above the troposphere is called

Which is the second region of the atmosphere?

The lower portion of atmosphere contains

___________ holds about 90% of all the ozone,which protect us from harmful ultraviolet sun rays.

Clouds and precipitation form in

Which is the closest layer to the Earth's surface?

The height of ______________ above the Earth's surface varies from place to place.

___________ keeps the Earth's surface warm at night.

___________ layer reflects the radio waves back to the surface of the Earth.

The first layer is called the