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Lowest region of the atmosphere, bounded by the Earth below and the stratosphere above, with the upper boundary being about 6–8 mi (10–13 km) above the Earth's surface. The troposphere is marked by decreasing temperature with height, which distinguishes it from the stratosphere. Most clouds and weather systems occur in the troposphere.
This entry comes from Encyclopædia Britannica Concise. For the full entry on troposphere, visit Britannica.com.