Atmosphere of Earth However, polar stratospheric or nacreous clouds are occasionally seen in the lower part of this layer of the atmosphere where the air is coldest. The stratosphere is the highest layer that can be accessed by jet-powered aircraft. The troposphere is the lowest layer of Earth's atmosphere. It extends from Earth's surface to an average height of about , although this altitude varies from about at the geographic poles to at the Equator, with some variation due to weather. The troposphere is bounded above by the tropopause, a boundary marked in most places by a temperature inversion (i.e. a layer of
What We Live For on the future. "Go Big or Go Home", which would ultimately appear as the seventh track on the final album, was released in May 2015 as a single, after the band's last single promoting "Oh, What a Life", "Luck", was released a year previously. "Pride" also appeared on a single in December 2015, and was also solicited as a promotional single to United States adult contemporary radio thereafter. "What We Live For" was officially unveiled by the band and Island Records on March 2, 2016, with pre-orders for both a digital download and compact disc version of the album being