In an interview posted on FirstScience.com the well-known British scientist and environmentalist James Lovelock, who proposed the Gaia hypothesis, had some things to say about geoengineering proposals to combat global warming which sounded rather positive. His extremely pessimistic view of the global warming situation and his advocacy of nuclear power as part of the answer have gotten a lot of press recently whereas his views on geoengineering seem to be relatively unknown. In the interview he comments on two specific schemes. One involves placing sunshades in space at the point between the Earth and the Sun that is gravity neutral. Lovelock says that “It would take a lot of time and a lot of politics to get it working, but it might happen.” The other scheme involves dispersing tiny particles of sulphuric acid into the stratosphere to reflect sunlight as way of mimicking the effects of an erupting volcano. According to Lovelock “if commercial airlines could burn sulphur-rich fuel (unrefined kerosene) as they fly, instead of the highly-refined stuff, it would put enough sulphur in the atmosphere to give you a Pinatubo every couple of years.”
These type of schemes are generally considered to be something to be used as a last resort if greenhouse gas emissions cannot be reduced to limit global warming. With greenhouse gas emissions now increasing worldwide at about 3% per year and no plan in sight to alter this trend the likelihood that a method of last resort will actually be used to try to stop global warming seems to be growing more likely every day.