New observations show that water vapor in the Martian atmosphere is supersaturated, leading to concerns of future destabilization of Mars’ atmosphere. The atmospheres of the planets have evolved over the thousands of millions of years since the birth of the solar system. Mars is, of course, further from the sun and is smaller than Earth, characteristics which have influenced its atmosphere over time.
In particular, the atmosphere of Mars is considerably thinner than that of Earth by a factor of over 100. Its atmosphere contains mainly carbon dioxide (95%), and nitrogen (3%) with trace amounts of oxygen and water vapor.
Water is a strong greenhouse gas, but because of its very low concentration in the Martian atmosphere, it causes a negligible warming effect on the surface. Nonetheless, the presence of water ice clouds in the martian atmosphere has an important influence on its climate.