Our atmosphere consists of several layers and each plays a different role in our climate. The bottom two layers are the troposphere and the stratosphere, and in between these two is a region of colder air known as the Tropopause. It is critical to understand the Tropopause, its composition and interaction with gases, aerosols, and humidity that affect the stratosphere's climate, which ultimately affects the climate in the troposphere. NASA launched a mission called Airborne Tropical TRopopause Experiment (ATTREX) to find answers to these questions.