Troposphere

[Raeanne Dimick]

The inner layer of the atmosphere below about 15 kilometers, within which there is normally a steady decrease of temperature with increasing altitude. Nearly all clouds form and weather conditions manifest themselves within this region. Its thermal structure is caused primarily by the heating of the earth and rsquo;s surface by solar radiation, followed by heat transfer through turbulent mixing and convection.

[Sommer]

The lowest region of the atmosphere, extending from the earths surface to a height of about 3.7–6.2 miles (6–10 km), which is the lower boundary of the stratosphere.

[Becky]

the layer of gases surrounding the earth from the surface up to a height of about ten kilometres