Giant mirrors to reflect sunlight away from Earth may be needed to hit climate targets, UN says
Giant mirrors positioned to reflect sunlight back into space may be needed to meet climate targets, according to a report from the United Nations.
Solar radiation modification (SRM), also known as solar geoengineering, is among the proposals from the UN Environment Programme to use radical technology to avoid a climate emergency.
“SRM is the only known approach that could be used to cool the Earth within a few years,” the report, compiled by an expert panel of climate scientists, stated.
“Climate model simulations consistently show that SRM could offset some of the effects of increasing greenhouse gases on global and regional climate, including carbon and water cycles, but there could be substantial residual or overcompensating climate change at the regional scales.”
The report found that more research is needed to be undertaken in order to better understand the environmental and social impacts of geoengineering technologies.
Other technologies mentioned in the report included injecting large quantities of aerosols into the upper atmosphere to block out the Sun.
It is not the first time that space mirrors have been proposed as a way of alleviating the worst effects of climate change, with former US presidential hopeful Andrew Yang notably publishing a plan to geoengineer the planet in 2019.
His proposal to place giant foldable space mirrors into orbit would cost $4.86 trillion and take around two decades to implement.
The UN noted that global efforts to reduce greenhouse gas emissions are not on track to meet the 1.5°C Paris Agreement goal.
Inger Andersen, the executive director of the UN Environment Programme, noted that SRM should not be considered a substitute for current targets to reduce emissions.
“It does not remove carbon from the atmosphere. Nor will SRM improve the environment or tackle the root causes of climate change,” she said.
“Our best bet for a prosperous and equitable future remains putting in the unavoidable hard work to achieve climate stability by reducing greenhouse gas emissions, to create a pollution-free planet and societies that live in harmony with nature.”