Are 'Hail Mary' Technological Solutions Our Only Hope to Prevent Disastrous Climate Change?

By Steve Connor, Independent UK. Posted January 2, 2009.

Among those who oppose geoengineering is Professor David Archer, a geophysicist at Chicago University and expert on ocean chemistry. "Carbon dioxide released to the atmosphere will continue to affect climate for many millennia," he said. "Relying on geoengineering schemes such as sulphate aerosols would be analogous to putting the planet on life support. If future humanity failed to pay its 'climate bill' -- a bill that we left them, thank you very much -- they would bear the full brunt of climate change within a very short time."

Gummer set for green role

The former Tory cabinet member who publicly fed his daughter a beefburger during the outbreak of so-called "mad cow disease" is in line for a leading role in helping the Government fight against global warming, writes Nigel Morris.

John Gummer, who served as Environment Secretary in the previous Conservative government, has been shortlisted for the post of chairman of the Committee on Climate Change. He is one of three candidates being discussed in Whitehall to succeed Baron Turner of Ecchinswell. The others are Rachel Lomax, a former Treasury official who has recently retired as a deputy governor of the Bank of England, and Sir John Harman, former chairman of the Environment Agency.

Mr Gummer, 69, has been a Conservative activist for almost half a century and has spent 34 years as an MP. He represents the safe seat of Suffolk Coastal. A 16-year spell in government culminated with his promotion by John Major to Environment Secretary, when he was regarded as a pioneering minister, introducing the landfill tax and the fuel-price escalator.

Mr Gummer said last night he knew nothing about the vacant post.

Fixing the planet Could technology help save the world?

Injecting the air with particles to reflect sunlight

Volcanic eruptions release huge amounts of sulphate particles into the upper atmosphere, where they reflect sunlight. After Mount Pinatubo erupted in 1991, sulphates reflected enough sunlight to cool the Earth by 0.5C for a year or two. The Nobel Laureate Paul Crutzen suggested in 2006 that it may be possible to inject artificial sulphate particles into the upper atmosphere -- the stratosphere. However, the idea does not address ocean acidification caused by rising CO2 levels. There may be side-effects such as acid rain and adverse effects on agriculture.

Creating low clouds over the oceans

Another variation on the theme of increasing the Earth's albedo, or reflectivity to sunlight, is to pump water vapour into the air to stimulate cloud formation over the sea. John Latham of the United States National Centre for Atmospheric Research in Boulder, Colorado is working with Stephen Salter of Edinburgh University and Mike Smith at Leeds to atomise seawater to produce tiny droplets to form low-level maritime clouds that cover part of the oceanic surface. The only raw material is seawater and the process can be quickly turned off. The cloud cover would only affect the oceans, but still lower global temperatures.

Fertilising the sea with iron filings

This idea arises from the fact that the limiting factor in the multiplication of phytoplankton -- tiny marine plants -- is the lack of iron salts in the sea. When scientists add iron to "dead" areas of the sea, the result is a phytoplankton bloom which absorbs CO2. The hope is that carbon taken up by the microscopic plants will sink to deep layers of the ocean, and be taken out of circulation. Experiments support the idea, but blooms may be eaten by animals so carbon returns to the atmosphere as CO2.

Mixing the deep water of the ocean

The Earth scientist James Lovelock, working with Chris Rapley of the Science Museum in London, devised a plan to put giant tubes into the seas to take surface water rich in dissolved CO2 to lower depths where it will not surface. The idea is to take CO2 out of the short-term carbon cycle, cutting the gas in the atmosphere. Critics say it may bring carbon locked away in the deep ocean to the surface.

Giant mirrors in space

Some scientists suggest it would be possible to deflect sunlight with a giant mirror or a fleet of small mirrors between the Earth and the Sun. The scheme would be costly and prompt debate over who controls it. Many scientists see it as contrary to the idea of working with the Earth's systems.

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