Ten years ago, the Paris Agreement set a bold goal: keep global warming below 1.5°C. But in 2023, Earth breached that threshold for the first time. Emissions are still climbing, and extreme weather is worsening. With the window for decisive climate action narrowing, scientists and policymakers are looking at once-unthinkable ideas, including deliberately cooling the planet.
This is where solar geoengineering, or solar radiation management (SRM), enters the conversation.
What is SRM?
At its core, SRM is about reflecting a small fraction of sunlight away from Earth to reduce temperatures. Proposals range from spraying reflective particles high in the stratosphere (mimicking the cooling effect of volcanic eruptions) to brightening clouds, or even deploying space mirrors. These methods are relatively cheap and can cool the planet quickly, but they don’t reduce greenhouse gases.
Why the Global South Matters
The paradox is stark: countries in the Global South could gain the most from SRM, but also stand to lose the most if it goes wrong. Many are already on the frontline of climate impacts, from droughts in the Sahel to flooding in South Asia, with fewer resources to adapt.
Yet, voices from the South remain underrepresented in SRM research. While global funding for SRM studies is rising, only about 2% goes to researchers in the Global South. That imbalance risks leaving those most affected with the least influence over decisions that could reshape their future.
Thankfully, initiatives like the Degrees Initiative are shifting the balance. In Cape Town, researchers from Jamaica, Indonesia, and South Africa recently presented studies on how SRM might alter rainfall, agriculture, or temperature extremes in their regions. According to the study, SRM could reduce malaria risk in some areas but worsen drought or crop failures in others.
Risks and Ethical Questions
SRM comes with profound uncertainties:
- Could it disrupt monsoon rains in West Africa?
- Could it worsen droughts while cooling global temperatures?
- Would it deepen inequalities by benefiting some regions while harming others?
- And perhaps most alarmingly, who decides if and when to use it?
The specter of “termination shock” looms large: if SRM were deployed and then suddenly stopped, global temperatures could spike rapidly, devastating ecosystems and societies.
Critics warn SRM could also become a dangerous distraction, a shiny Plan B that allows major emitters to delay the real work of decarbonization.
Between Necessity and Caution
UN Secretary-General António Guterres has warned that “humanity has opened the gates of hell.” For some, this justifies exploring SRM as an emergency brake to buy time for deeper climate action. Others argue for a global moratorium, fearing geopolitical misuse or unintended consequences.
The Global South cannot afford to be a passive observer in this debate. Whether or not SRM is ever deployed, Southern expertise, governance, and ethical leadership must shape the conversation.
Solar geoengineering may never leave the laboratory. Ideally, the world accelerates emissions cuts, scales renewables, and adapts resiliently, making SRM unnecessary. But as the planet warms past thresholds once thought unbreakable, dismissing SRM outright may be naïve.
The real challenge is ensuring that decisions about such radical technologies are inclusive, transparent, and globally just. For Africa, Asia, and Latin America, regions where climate change already defines daily life, the time to claim a seat at the table is now.
