Should we engineer the climate to counter the effect of global warming?

By James Dacey

Geoengineering is the idea of controlling the weather and climate by the large-scale engineering of the environment. The idea has come to prominence in recent years as concerns about man-made global warming have increased and governments have faltered on negotiations to restrict carbon-dioxide emissions.

One of the more radical proposals is to intervene with the Earth’s solar-energy balance by deploying technologies to reflect sunlight. Suggestions include painting buildings white to make them more reflective, injecting reflective aerosols into the atmosphere, or even deploying a fleet of shields into the Earth’s orbit to directly intercept incoming sunlight.

The other main approach to geoengineering is to try to directly remove carbon dioxide from the atmosphere. One area already being developed is carbon capture and storage (CCS), a three-stage process that involves harvesting, transporting and then storing the carbon dioxide in suitable underground locations such as vast saline aquifers. A more radical approach is to fertilize the ocean with a limiting nutrient such as iron to promote more marine flora, which will draw more carbon out of the atmosphere during photosynthesis.

Earlier this week we published an interview with the high-profile geophysicist Ken Caldeira of the Carnegie Institution for Science in the US. Caldeira has some severe reservations about geoengineering, specifically concerning: its environmental impact; how the presence of a “plan B” that may prove unreliable could affect efforts to cut carbon emissions; and who on the global stage should regulate use of the technology, particularly when it may reduce rainfall in some areas.

We want to know your opinion on this issue, via this week’s Physics World Facebook poll.

Should we engineer the climate to counter the effect of global warming?

Let’s do it!
We should prepare to do it as a “plan B” if carbon emissions continue to rise
No way! The environmental risks are too high
No, because it won’t work anyway

Have your say by casting your vote on our Facebook page. As always, please feel free to explain your response by posting a comment.

In last week’s poll we looked at the issue of university ranking exercises. The issue was on our minds because the Times Higher Education (THE) had just released its annual list of the top 100 universities, which was dominated by institutions in English-speaking countries. We asked whether you think these university ranking exercises are inherently biased. The outcome was highly conclusive, with 96% of respondents opting for “yes”.

Thank you for your participation and we look forward to hearing from you in this week’s poll.