Water vapor accounts for roughly 0.25% of the atmosphere by mass.The concentration of water vapor (a greenhouse gas) varies significantly from around 10 ppm by volume in the coldest portions of the atmosphere to as much as 5% by volume in hot, humid air masses, and concentrations of other atmospheric gases are typically quoted in terms of dry air (without water vapor).The atmosphere of Earth protects life on Earth by creating pressure allowing for liquid water to exist on the Earth's surface, absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night (the diurnal temperature variation).By volume, dry air contains 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.04% carbon dioxide, and small amounts of other gases.
The exosphere is located too far above Earth for any meteorological phenomena to be possible.
The Kármán line, at 100 km (62 mi), or 1.57% of Earth's radius, is often used as the border between the atmosphere and outer space.
Atmospheric effects become noticeable during atmospheric reentry of spacecraft at an altitude of around 120 km (75 mi).
Early pioneers in the field include Léon Teisserenc de Bort and Richard Assmann.
The three major constituents of air, and therefore of Earth's atmosphere, are nitrogen, oxygen, and argon.Sisällön luominen “tylsien” B2B-alojen yrityksille voi tuntua haasteelliselta.