4 February 2005
Super Greenhouse Gases Could Help Terraform Mars
by Kate Melville
A team of researchers believe that introducing global warming on Mars may be the best approach for warming the planet's frozen landscape and turning it into a habitable world in the future. The report, published in the Journal of Geophysical Research, suggests that seeding synthetic "super" greenhouse gases into the Martian atmosphere could raise the planet's temperature enough to melt its polar ice caps and create conditions suitable for sustaining biological life.
Margarita Marinova and colleagues propose that the same types of atmospheric interactions that have led to recent warming trends on Earth could be harnessed on Mars to create a biologically hospitable environment. "Bringing life to Mars and studying its growth would contribute to our understanding of evolution, and the ability of life to adapt and proliferate on other worlds," Marinova said. "Since warming Mars effectively reverts it to its past, more habitable state, this would give any possibly dormant life on Mars the chance to be revived and develop further."
The authors note that artificially created gases - which would be nearly 10,000 times more effective than carbon dioxide - could be manufactured to have minimal detrimental effects on living organisms and the ozone layer while retaining an exceptionally long lifespan in the environment. Their study focused on fluorine-based gases, composed of elements readily available on the Martian surface, that are known to be effective at absorbing thermal infrared energy. They found that a compound known as octafluoropropane, whose chemical formula is C3F8, produced the greatest warming, while its combination with several similar gases enhanced the warming even further.
The researchers say that adding approximately 300 parts per million of the gas mixture in the current Martian atmosphere, which is the equivalent of nearly two parts per million in an Earth-like atmosphere, would spark a runaway greenhouse effect, creating an instability in the polar ice sheets that would slowly evaporate the frozen carbon dioxide on the planet's surface. They add that the release of increasing amounts of carbon dioxide would lead to further melting and global temperature increases that could then enhance atmospheric pressure and eventually restore a thicker atmosphere to the planet. The authors conclude that introducing powerful greenhouse gases is the most feasible technique for raising the temperature and increasing the atmospheric pressure on Mars although such a process could take centuries or even millennia to complete.