Stratospheric Aerosol Injection
Stratospheric Aerosol Injection (SAI) is a climate engineering technique aimed at reflecting a small portion of the sun's radiation back into space to reduce global temperatures. This method involves dispersing fine particles, such as sulfur dioxide, into the stratosphere, where they form sulfate aerosols. These aerosols act like tiny mirrors, scattering sunlight and thereby creating a cooling effect similar to the natural phenomena observed after major volcanic eruptions.
The concept of SAI is rooted in observations of volcanic activity, which have shown significant, albeit temporary, reductions in global temperatures. For instance, the eruption of Mount Pinatubo in 1991 released large quantities of ash and sulfur dioxide into the stratosphere, leading to a noticeable drop in global temperatures for several years. By mimicking this natural process, SAI holds the potential to mitigate some impacts of climate change.
However, Stratospheric Aerosol Injection is not without its challenges and controversies. The technique raises numerous environmental, ethical, and geopolitical questions, such as potential disruptions to weather patterns, impacts on the ozone layer, and the governance of global climate interventions. Ongoing research aims to better understand these implications, ultimately weighing the benefits of SAI as a supplementary tool in our fight against climate change.