Stratopause

The stratopause is the boundary layer in Earth's atmosphere located roughly between 50 to 55 kilometers (about 31 to 34 miles) above the Earth's surface. It marks the transition point where the temperature stops increasing with altitude in the stratosphere and begins to decrease again in the mesosphere. Think of it as a "ceiling": within the stratosphere, temperatures warm with height, but at the stratopause, this trend reverses. It's an important feature that affects how layers of atmosphere interact and how weather and climate processes unfold above us.