What is the lowest level of the atmosphere called?

The lowest level of the atmosphere is known as the troposphere. This layer starts at the Earth's surface and extends to about 8 to 15 kilometers (5 to 9 miles) high, depending on location and weather conditions. It is where we live and where most weather phenomena occur, such as clouds, rain, and storms.

The troposphere plays a crucial role in supporting life on Earth because it contains most of the atmosphere's mass and the majority of its water vapor. As altitude increases in this layer, temperature generally decreases, which is a key factor in weather patterns and climatic conditions.

The other atmospheric layers—stratosphere, mesosphere, and thermosphere—are positioned above the troposphere and have distinct characteristics that differentiate them from the troposphere. For example, the stratosphere contains the ozone layer, which protects the Earth from harmful ultraviolet radiation, while the mesosphere is where meteoroids burn up upon entering the atmosphere. The thermosphere, characterized by high temperatures and low density, is where phenomena like the auroras occur. Each layer has unique properties and functions, but the distinction of the troposphere as the lowest layer is critical for understanding weather and climate systems.