By 7000 AD, Venus could feasibly have been terraformed, according to Martyn J. Fogg in Terraforming: Engineering Planetary Environments.
Using these plans, Zio sends a research team to Mars to begin the Terraforming Project, which causes the Martian surface and atmosphere to approximate that of Earth.
When rejected by the suspicious humans, the Angels resort to sabotage on a planetary scale, using terraforming equipment from the Challenger to melt Paradise's polar ice caps and thus raise the sea level in an attempt to get their former crew to rejoin them on the ship.
Martyn J. Fogg rebutted these ideas by delineating four potential rationales on which to evaluate the ethics of terraforming—anthropocentrism, zoocentrism, ecocentrism, and preservationism—roughly forming a spectrum from placing the most value on human utility to placing the most value on preserving nature.
According to the 1997 Virgin New Adventures novel Eternity Weeps by Jim Mortimore, Liz dies in 2003, the victim of an extraterrestrial terraforming virus contracted while she was part of a UNIT team investigating an alien artefact on the Moon, despite the efforts of the Seventh Doctor and his current companion Chris Cwej to save her.
#Planetology: reductions in the cost of pollution control; colonization of hostile planets; terraforming, which increases the maximum population of a planet; the ability to increase populations more efficiently; biological weapons and defenses against such weapons.
To alleviate environmental pressures and overpopulation, the FEN began expanding into space, constructing space colonies and asteroid cities, as well as an Orbital Space Ring around the Earth, and the development and terraforming of the Moon and Mars.