Atmosphere of Earth (see the temperature section, below). Because the general pattern of the temperature/altitude profile is constant and measurable by means of instrumented balloon soundings, the temperature behavior provides a useful metric to distinguish atmospheric layers. In this way, Earth's atmosphere can be divided (called atmospheric stratification) into five main layers. Excluding the exosphere, the atmosphere has four primary layers, which are the troposphere, stratosphere, mesosphere, and thermosphere. From highest to lowest, the five main layers are: The exosphere is the outermost layer of Earth's atmosphere (i.e. the upper limit of the atmosphere). It extends from the exobase, which is located at
What We Live For "we tried to take a lot of the stuff that our fans like and love about us from Oh, What a Life and take that to the next level as far as sounds go. [We] brought back some of the old instruments like mandolin and banjo, but also experimented with a lot of different sounds like vocal samples. We brought back a lot of piano [and] bigger harmonies." Lyrically, the album builds on "Oh, What a Life"s biographical themes, which followed the band's origins and journey; "What We Live For" documents the band's experiences during the present and their perspective