Engineering solutions to modify the Earth’s environment and climate may be necessary if humanity is to adapt to global warming, a group of influential scientists announced today. Technological fixes such as encouraging cloud formation and increasing the amount of carbon dioxide absorbed by the oceans have the potential to limit climate change, according to papers published in a special issue of the journal Philosophical Transactions of the Royal Society.

The experts, however, also give warning that there is no guarantee that such ingenious schemes will work, and that so-called geo-engineering needs to be assessed properly to ensure that it does not cause more problems than it solves.

Professor James Lovelock, the environmental scientist who developed the Gaia hypothesis of the Earth as a self-regulating organism, likened geo-engineering to 19th-century medicine — a tool that might sometimes work, but was generally too primitive to stave off disaster.

“Whether or not we use … geo-engineering, the planet is likely, massively and cruelly, to cull us, in the same merciless way we have eliminated so many species by changing their environment into one where survival is difficult,” he said. “Before we start geo-engineering, we have to raise the following question: are we sufficiently talented to take on what might become the onerous permanent task of keeping the Earth in homeostasis [balance]?”

He raised the example of introducing aerosols into the stratosphere to induce a cooling effect. While this might have positive effects, it would not address ocean acidification, a separate problem caused by rising carbon emissions, which would then require another engineering solution. “We have to consider seriously that as with 19th-century medicine, the best option is often kind words and painkillers but otherwise do nothing and let Nature take its course,” Professor Lovelock said.