The net effect is that most of the outgoing radiation is kept within the atmosphere instead
of escaping into space.
When water molecules rise high in an atmosphere, ultraviolet radiation split the water molecules into its component gases, oxygen and hydrogen, and the lighter hydrogen
molecules escape into space.
Most of this precious
liquid escaped into space, but some of it stayed behind, transforming into ice and settling beneath the rocky surface.
You also say that most of the reflected energy
actually escapes into space, which would be a good thing from a global warming perspective.
The free hydrogen
easily escapes into space, Dan Garisto reported in «Massive dust storms are robbing Mars of its water» (SN: 2/17/18, p. 8).
And, what ends up mattering there is, essentially, what level the radiation that
does escape into space (as opposed to being re-absorbed) is emitted from.
Because light isotopes of krypton
escape into space more quickly than heavy isotopes, the atmosphere can only get «heavier»
In addition, we'll see auroral activity thanks to coronal holes — openings in the Sun's magnetic field that let its powerful solar
wind escape into space.
But Catling's team proposes instead that the hydrogen
escaped into space through a process called methane photolysis, in which the hydrogen - containing methane reacts with oxygen such that hydrogen atoms are freed.
A global magnetic field might have funnelled enough energy into the atmosphere to push lighter
particles escape into space, like steam from a pot of boiling water, for example.
As Mars Express flies in polar orbit, dipping to within 155 miles of the planet spinning beneath it, instruments made in Sweden, France, and Italy will map the composition of the atmosphere, looking in part for evidence that vestiges of that water are
still escaping into space.
However, because greenhouse gases like carbon dioxide are strong absorbers of infrared radiation, this radiation can
only escape into space at high levels in the atmosphere, where the concentration of these greenhouse gases is very low.
First, returning CO2 concentration to below 350 ppm would restore the energy balance of Earth and allow as much heat to
escape into space as Earth retains, which has kept our planet in the sweet spot for humans and other species to thrive.
Re-absorption by other greenhouse gas molecules complicates the path and destination of an individual unit of IR, but what it all boils down to is that something less than half of the IR absorbed by greenhouse gases eventually finds its way back to the surface, with the
remainder escaping into space.
... Infrared radiation is carried slowly aloft by air currents, and its
eventual escape into space is delayed by greenhouse gases» (emphasis added).
Carbon dioxide acts something like the glass panes in a greenhouse, allowing sunlight in to heat the Earth, but preventing some of that heat
from escaping into space.
But this combustion process also produces carbon dioxide, which is a greenhouse gas that accumulates in the atmosphere for thousands of years and traps heat that would
otherwise escape into space, causing global climate change.
Venus Express has also detected water
molecules escaping into space, found concrete evidence for lightning in the venusian atmosphere, and provided infrared glimpses of the hot surface.
But Unterborn doesn't think the TRAPPIST - 1 planets are massive enough to hold onto much of an atmosphere — it would
probably escape into space.
The spacecraft pioneered the detection of aurorae at mid latitudes, provided estimates on the rate at which Mars»
atmosphere escapes into space, and studied the Martian moon Phobos at close quarters.
The lighter isotope would then have
escaped into space more rapidly, leaving proportionately more deuterium behind.
Nor could water have migrated into those craters from inside or on Mercury without becoming hot water vapor (or dissociated H, O, and OH) that would
quickly escape into space.