Scientists in several developing nations announced plans to ramp up research efforts studying the effects of solar radiation management (SRM) engineering, and ask world leaders to do the same.
Also called “solar engineering”, the controversial method works as a chemical “sunshade” by spraying tiny reflective particles into the upper atmosphere to filter the sun’s energy and reflect incoming sunlight. It’s believed it would cool the earth, curbing the effects of climate change.
But scientists aren’t certain what other consequences might arise.
"Clearly SRM could be dangerous but we need to know whether, for countries like Bangladesh, it would be more or less risky than passing the 1.5°C warming goal agreed by the UNFCCC,” said lead author Atiq Rahman.
Scientists and NGO leaders from 12 countries co-signed the commentary published in Nature. Facing higher temperatures, changes to rainfall patterns, and more erratic and intense weather, the writers say developing nations are most vulnerable to global warming and should be central in international efforts to understand how SRM works.
“Developing countries must be in a position to make up their own minds. Local scientists, in collaboration with others, need to conduct research that is sensitive to regional concerns and conditions,” they wrote.

Early last year, Harvard’s solar geoengineering research program and other US scientists announced plans to complete to small-scale test dispersals into the atmosphere by 2022. The first would use water, the second calcium carbonate particles.
A leaked draft of a report from a UN panel of climate experts says the organization is skeptical about solar geoengineering, according to Reuters, going on to say that SRM could be “economically, social, and institutionally infeasible.” Others argue it's a temporary solution that will wreak havoc on the world’s ecosystem rather than addressing the actual issue of cutting carbon emissions.
“The emissions cuts agreed in Paris are not enough — they will take the world to a 3°C rise. Adaptation is therefore essential,” say the authors.
Whether or not it should ultimately be used remains to be decided. In the comment, the authors say they aren’t advocating for its use, but deem necessary further research to understand its “safety and effectiveness”.
"Solar geoengineering is outlandish and unsettling. It invokes technologies that are redolent of science fiction — jets lacing the stratosphere with sunlight-blocking particles, and fleets of ships spraying seawater into low-lying clouds to make them whiter and brighter to reflect sunlight,” say the authors. “Yet, if such approaches could be realized technically and politically, they could slow, stop or even reverse the rise in global temperatures within one or two years.”
The comment was published after a $400,000 research project was announced earlier this week by the Solar Radiation Management Governance Initiative (SRMGI). Financing is provided by the Open Philanthropy Project.