Considering the most recent discovery, up until this year, the southern ice cap was thought to be filled with mostly CO2. In January of 2003, two scientists announced the discovery that the ice cap is made primarily of water. This changes the plans of melting the ice cap and creating a greenhouse effect. With this discovery, terraforming was thought to be completely impossible. In order to understand this discovery, the Earth’s atmosphere must be considered. Earth’s atmosphere contains about 1% CO2 or 1/2850ths of atmospheric composition. Of the 1000 millibars of atmospheric pressure, about 0.35 millibars of CO2 exist in gaseous state, while oxygen makes up about 209 millibars. There is about 1.36 billion cubic kilometres of water, about 2% of the atmosphere is water vapour and 1.6% is frozen in polar ice caps and glaciers with only a very small amount, about 0.36%, in underground aquifers.
The atmospheric pressure on Mars is about 8 millibars throughout which is the equivalent of thirty five thousand meters above the Earth. At around three thousand meters, Acute Mountain Sickness would kick in, which is at about 675 millibars. Since Mars is so far from the sun, the pressure has to be raised even more. The Global Surveyor found about 95.3% carbon dioxide and 0.021% water vapour in the atmosphere of Mars. If we were to terraform and raise the pressure to 675 millibars using PFC’s and oxygen from plants, the carbon dioxide level would reach about 1.128%, which is under the fatal level of 10%. The water vapour level would drop to about 0.00025%, which is much dryer than the Earth’s.
If the southern ice cap were melted with its original predictions of mostly carbon dioxide, the result would be a pressure rise of somewhere between fifty and one hundred millibars creating between 8.5% and 15.9% carbon dioxide at 675 millibars. With only a small amount of water vapour, the northern ice cap and the underground aquifers, luck would be needed to reach Earth’s proportions.
Everything changes with the new discovery. Instead of six to nine million cubic kilometres of CO2, there are six to nine million cubic kilometres of ice water. At 675 millibars, the 1% of carbon dioxide would be much better than the original 11%. This is very good for biologists and lends support to the hunt for ancient or present-day life. The terraforming process is actually made easier thanks to the loss of carbon dioxide. Mars has huge abundance of water that could form future oceans. There is a perfect combination of gasses so that when the pressure is raised, Mars will support life. The plan to increase the atmospheric pressure involves the use of perfluorocarbons.