Scientists recently convened by UNEP say in a report that this technology for SRM is no substitute for rapid reduction of greenhouse gas emissions, which must remain the global priority. “Climate change is taking the world into the unknown and the search for all viable solutions is underway,” says Andrea Hinwood, UNEP’s chief scientist. However, all new technologies must be clearly understood and potential risks or consequences identified before they are implemented,” she adds.
For the scientist, the private sector and regulators must address the fundamental uncertainties surrounding these technologies, answer some basic safety questions, and apply the precautionary principle before SRM can even be considered. According to UNEP, temporary emergency measures like SRM are being talked about in scientific and public discourse because global efforts to reduce greenhouse gas emissions are not on track to meet the 1.5°C target set by the Paris Agreement. “Climate change continues to worsen, and some of its effects are already irreversible. Indeed, SRM aims to cool the Earth rapidly by reflecting a small percentage of sunlight back to space.
Although some SRM technologies, such as stratospheric aerosol injection (SAI), are more advanced and open-air experiments are being actively pursued, the study reveals critical unresolved issues,” the same source said. The panel believes that SRM does not address the causes of climate change and will not correct or alter the effects we are already witnessing.
UNEP also reports that the effects of SRM technologies in low- and middle-income countries remain understudied, even though these countries are often on the front lines of climate change and would face these potential effects. The panel believes that large-scale deployment of SRM in the short to medium term is not warranted and would be unwise at this time. However, this view could change if climate action remains insufficient, the same source explains.