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
Where We Are Tour: Live from the O2 the music video of "What About Now". According to description released:‘The Where We Are Tour: Live From The 02’ also gives fans a rare, intimate glimpse into the lives of Nicky Byrne, Kian Egan, Mark Feehily and Shane Filan with the bonus ‘Where We Are – The Documentary’. This compelling behind the scenes documentary provides a fly on the wall insight into the lives of the band in the run up and during the tour. The boys also chat exclusively about why this tour meant so much to them. Both the DVD and Blu-ray versions will also include the epic