Geoengineering is at state of its development where large-scale deployment, even for testing purposes, would be incredibly reckless. The possibility of perturbing the climate in ways that cannot be predicted, and whose environmental effects are fully unknown, is both irresponsible and unethical.
The UK Government should not permit this or any similar activity: https://www.independent.co.uk/news/uk/home-news/block-sunlight-british-scientists-global-warming-b2740295.html
Further, the international community should broadly prohibit geoengineering as a climate policy option: https://www.solargeoeng.org/non-use-agreement/open-letter/
