Solar Radiation Management

Written by Aanya Deshpande

Overview 

Solar Radiation Management is one of the diverse branches of the desperate attempts to repair global warming. The idea behind SRM is to reflect radiation back into space, to keep it from becoming trapped by the greenhouse gasses in our atmosphere and therefore heating up the earth. It is essentially the idea of reflective shields which will cast sunlight back into space. This idea comes with many challenges and is still considered one of the last measures when climate change becomes uncontrollably out of hand. 

Stratospheric Aerosol Injection 

Another proposal was stratospheric aerosol injection. This involves placing reflective particles such as sulfur dioxide or calcium carbonate into the upper atmosphere. The idea is to replicate the cooling period of volcanic activity. For example, the eruption of Mount Pinatubo in the Philippines in 1991 released 20 million tons of sulfur dioxide, some of which reached the upper atmosphere. This caused the Earth's average temperature to be reduced by 0.5 degrees Celsius for about 18 months. Stratospheric aerosol injection is an attempt to replicate this feat, but the unnatural imitation might upset nature. Forecasts suggest that this execution of SRM could affect rainfall patterns, and seasonal changes, deplete stratospheric ozone, and perhaps even harm biodiversity. 

Ocean Albedo Modification 

An option that corresponds to the Albedo Modification and the ocean would be to use microbubbles to increase the reflectivity of the ocean. Breaking waves on the surface of the ocean form white caps during wind conditions. Whitecaps are breaking waves that trap and suspend small bubbles of air. Breaking waves on beaches also form white water or “foam” due to the same process. The formation of these tiny bubbles of air or microbubbles in white caps and white water turns the color of the ocean white. Because white surfaces reflect light, microbubbles reflect sunlight into space. The idea is to geoengineer the ocean by injecting more microbubbles of air to increase the formation of white foam, and therefore increase the ocean’s reflectivity and cool it. 

References

https://www.wilsoncenter.org/article/solar-radiation-management 

https://www.nrdc.org/onearth/dept-solar-radiation-management 

https://www.energy.gov/eere/solar/solar-radiation-basics 

https://geoengineering.global/solar-radiation-management/

Written by Aanya Deshpande from MEDILOQUY