- Lowest layer of atmosphere
- ~8km deep at poles, ~16km deep at equator. Depth varies both spatially & with time.
- Region where virtually all ‘weather’ occurs. Most of the water vapour in the atmosphere is concentrated in the lower troposphere.
- Temperature generally decreases with altitude (though with significant variability)
- Capped by a region of increasing temperature (a temperature inversion) or isothermal layer, the Tropopause.
- The tropopause acts as a lid, preventing the exchange of air between troposphere and stratosphere