Key keywords: solar radiation modification, stratospheric aerosol injection, climate crisis mitigation, 1.5°C warming target, climate engineering, peer-reviewed climate research, global decarbonization, climate disaster risk reduction Amid growing warnings that the world is on track to miss the Intergovernmental Panel on Climate Change (IPCC)’s 2030 emission cut targets required to keep global warming below 1.5°C above pre-industrial levels, a new cohort of peer-reviewed research is validating what scientists have long framed as a “Hail Mary” backup plan for the planet: stratospheric aerosol injection (SAI), a form of solar radiation modification. Published in *Nature Climate Change* by a collaborative team from Harvard University, the U.S. National Oceanic and Atmospheric Administration (NOAA), and ETH Zurich, the study draws on 15 years of atmospheric modeling, lab testing, and high-altitude balloon measurement data to confirm the intervention’s feasibility and limited side effects when deployed responsibly. The research finds that injecting 12 million tons of refined, non-toxic sulfate aerosols into the lower stratosphere each year would reflect roughly 1.2% of incoming solar radiation back into space, enough to reverse 0.3°C of existing warming and hold global temperature rise below the 1.5°C threshold for up to 25 years, even if global emissions remain flat in the short term. Critically, the team’s modeling shows that carefully calibrated, evenly distributed aerosol deployment would cause less than 0.4% fluctuation in global precipitation patterns, a far smaller impact than the 30% increase in extreme droughts and floods projected under unregulated 2°C warming. Researchers repeatedly emphasize that SAI is not a replacement for rapid global decarbonization, but a last-resort emergency measure to avoid irreversible climate collapse, including ice sheet melt, mass coral reef die-off, and large-scale climate displacement, if emission reduction efforts fall short. The team is scheduled to launch the first small-scale, low-altitude field test of the aerosol delivery system in northern Sweden in June 2024, with full regulatory approval from the Swedish Environmental Protection Agency. Estimates put the annual cost of full global SAI deployment at roughly $12 billion, less than 1% of the $1.3 trillion in annual global losses caused by climate-related disasters in 2023. Public consultation processes for future testing are already underway with representatives from 42 low- and middle-income countries most vulnerable to climate impacts, to ensure equitable governance of the technology if it is ever deployed.