Solar Geoengineering Non-Use Agreement

As the climate catastrophe unfolds, there is a desperate search for solutions, with a general agreement that there is no one solution, but many needed together. The debate is not always objective, as the corporate sector always prefers approaches that will generate the maximum profits, and fossil fuel interests lobby for solutions that will allow them to continue extracting fossil carbon and somehow capture it or remove it from the atmosphere later. Then there are those that always prefer technological fixes over the role of nature for the above reasons, and those who point the finger at consumer demand to make us feel guilty and responsible, rather than the producers who knowingly created the climate problem.

Given our failure for decades to control the supply of fossil fuels, and the accelerating global heating we are now experiencing, there is panic about the need for quick fixes, and solar geoengineering (also known as solar radiation management or modification, SRM), is one now receiving serious consideration. Since greenhouse gases in the stratosphere trap heat from the sun, the suggestion is to put something in the atmosphere to block some incoming solar radiation and thus cool the planet to counteract excessive global warming. There is no need here to go into detail about the substances proposed and the ways they could be introduced into the stratosphere with missiles or aircraft. The problem is in the impacts this might have on the Earth system and possible surprises. Furthermore, there is no way today to stop anyone from experimenting or trying full-scale measures without global agreement.

One example of how dangerous this could be is a recent study in Europe that showed plant productivity was higher on the weekend than during the week, because air pollution by aerosols, which block sunlight just as solar geoengineering would, is less on the weekends. Plant photosynthesis, the process by which plants convert sunlight into the energy-containing compounds at the base of all food chains, is thus highly sensitive to any shading of the sun. Imagine the impact if photosynthesis was reduced globally, on land and in the sea, with less energy available to maintain all ecosystems, as well as our food crops.

The Solar Geoengineering Non-Use Agreement would stand against such emerging initiatives to explore planetary techno-fixes as a climate policy option. Solar geoengineering deployment at planetary scale cannot be fairly and effectively governed in the current system of international institutions. It also poses unacceptable risk if ever implemented as part of future climate policy. A strong political message from governments, the United Nations and civil society is urgently needed. The organisers have prepared an Open Letter calling for an International Non-Use Agreement on Solar Geoengineering, which is open for signature on their website: https://www.solargeoeng.org/.