Geoengineering: The promise and its limits

Introduced by Dr Brian Iddon MP, Dr Alan Gadian from the University of Leeds opened the seminar with a description of cloud albedo modification, explaining how a “cloud whitening scheme”, involving ships spraying small droplets of seawater up into the atmosphere, could help in the fight against climate change.

Dr Gadian was followed by Dr Dan Lunt from the University of Bristol, who in his presentation about sunshade engineering, described the most up-to-date range of CO2 forecasts currently being used by environmental scientists, the implications of those forecasts and how much benefit the positioning of sunshades in space, placed directly between the Earth and the Sun, held in place by gravitational forces, could have.

Following Dr Lunt, Professor Andrew Watson from the University of East Anglia discussed ocean fertilisation; dropping iron, nitrates and phosphorous in the sea to encourage the growth of plankton colonies which can sequester oceanic CO2.

Akin to the previous speakers, Professor Watson explained the boundaries and limits to this anthropogenic effort to adapt the atmosphere, “All of these ideas need further research before they can be implemented and they, at best, will only provide part of the solution.”

The three scientific talks were followed by a presentation from Professor Steve Rayner, a social scientist from the University of Oxford, who discussed the social and ethical implications of undertaking projects to alter the Earth's natural atmosphere.

Raising the issue of moral hazard, Professor Rayner suggested that, after 50 years of telling people it is bad to put things in, or tamper with, the Earth's atmosphere, making geo-engineering projects acceptable to the general public is going to be a hard sell.

The four talks were followed by questions from the audience on a wide range of topics: From the likely prominence of geo-engineering issues at the upcoming international climate conference, COP 15 in Copenhagen; to the level of urgency and the imminence of the climate threat we face; the money available for research projects such as those described in the talks; and, quite controversially, the issue of population control.