The difference is that air molecules can release their energy to
space via radiation.
Understanding how the earth and atmosphere cool to
space via radiation is a critical component in understanding surface temperature changes.
Not exact matches
It was the first cosmic event in history to be witnessed
via both traditional telescopes, which can observe electromagnetic
radiation like gamma rays, and gravitational wave detectors, which sense the wrinkles in
space - time produced by distant cataclysms.
CO2 reduces the rate at which the atmosphere loses its energy to
space via infrared
radiation, which in turn reduces the flow of energy from the Earth's surface to the atmosphere.
The only way heat can escape to
space is
via radiation because
space is a void and therefore heat can not be transmitted by convection or conduction.
The major outflow of heat from the air is
via radiation and convection (dry air being a very good insulator) The ocean loses energy to the air, which in turn, loses it, ultimately, into
space.
A side point here is that the ocean loses heat by
radiation to both the air (thanks to greenhouse gases) and to
space, and to the atmosphere by direct conduction and this,
via convection and
radiation, ultimately to
space.
Although
radiation to
space occurs over the whole planet there is a general movement of heat from equator to poles
via the oceans and atmosphere.
A small localized change in surface temperature can cause a convection burst (thunderstorm) and a large increase in convection height, improving both reflection of incoming solar
radiation, and conveying sensible heat to a higher altitude where it can then escape to
space via radiative processes with far less interference.
Heat always moves from warmer to colder, so it must move, through whatever means, from the tropics to the arctic or,
via radiation, to outer
space.
That is determined by consideration of the absorption of the atmosphere of terrestrial
radiation (and
radiation emitted by the atmosphere), which essentially ends up determining at what altitude the temperature has to be determined
via radiative balance between the Earth system (earth + atmosphere) and the sun and
space [which for the earth system with its current albedo is ~ 255 K].
There may be convection and conduction within the atmosphere (up to about 10 Km as found by E. O. Hulburt in 1931), but between the Earth (including the atmosphere) and «
space», heat is transferred
via radiation since
space is a vacuum (you need matter for conduction and convection, also shown by Hulburt in 1931).
It is possible to measure the infrared radiance in CO2 - band wavelengths
via satellite from
space, and at ground level for downwelling infrared
radiation.