Stratospheric aerosol injection

<p>Stratospheric aerosol injection (SAI) is a proposed method of <a href="/facts/Solar_geoengineering/Ho5UblE7">solar geoengineering</a> (or solar radiation modification) to reduce <a href="/facts/Global_warming/rEN4BDE7">global warming</a>. This would introduce <a href="/facts/Aerosol/X1jXFLp2">aerosols</a> into the <a href="/facts/Stratosphere/taBra67V">stratosphere</a> to create a cooling effect via <a href="/facts/Global_dimming/JBMzvfYk">global dimming</a> and increased <a href="/facts/Albedo/TJDRdKEB">albedo</a>, which occurs naturally from <a href="/facts/Volcanic_winter/SAnA3nsU">volcanic winter</a>. It appears that stratospheric aerosol injection, at a moderate intensity, could counter most changes to temperature and precipitation, take effect rapidly, have low direct implementation costs, and be reversible in its direct climatic effects. The <a href="/facts/Intergovernmental_Panel_on_Climate_Change/sh76du1u">Intergovernmental Panel on Climate Change</a> concludes that it "is the most-researched [solar geoengineering] method that it could limit warming to below 1.5 °C (2.7 °F)." However, like other solar geoengineering approaches, stratospheric aerosol injection would do so imperfectly and other effects are possible, particularly if used in a suboptimal manner.
</p><p>Various forms of <a href="/facts/Sulfur/IK0amTfM">sulfur</a> have been shown to cool the planet after large volcanic eruptions. <a href="/facts/Atmospheric_entry/p7TMk9sa">Re-entering satellites are polluting</a> the stratosphere. However, as of 2021, there has been little research and existing aerosols in the stratosphere are not well understood. So there is no leading candidate material. <a href="/facts/Alumina/wXM9P6pI">Alumina</a>, <a href="/facts/Calcite/gKMHYQJo">calcite</a> and salt are also under consideration. The leading proposed method of delivery is custom aircraft.
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Stratospheric aerosol injection open-in-new

Stratospheric aerosol injection