What is the troposphere?

The troposphere is indeed the layer of Earth's atmosphere closest to the surface. This layer extends from the ground up to about 8 to 15 kilometers (5 to 9 miles) depending on your location (thicker at the equator and thinner at the poles). It is the part of the atmosphere where we experience weather phenomena such as rain, snow, and storms, and it contains most of the atmosphere's mass, including water vapor.

The characteristics of the troposphere make it vital for life on Earth, as it holds the air we breathe and is the site of most atmospheric processes. As altitude increases within this layer, temperature generally decreases, which is another defining feature. Other layers of the atmosphere, such as the stratosphere above it, differ in composition, temperature gradients, and function, which further emphasizes the uniqueness of the troposphere.