Solar Geoengineering

Solar Geoengineering

News: The United States is eyeing a controversial tool to counter global warming: Solar radiation management (SRM), which involves reflecting a small fraction of sunlight into space.

Background:
• In a report released June 30, 2023, the White House stated that public or private actors could carry out activities such as injecting aerosols and brightening marine clouds to reflect more sunlight into space.

What is Solar Geoengineering?
• Solar geoengineering is a type of climate engineering that aims to reflect some sunlight back into space to limit or offset human-caused climate change.
• There are different methods of solar geoengineering, such as stratospheric aerosol injection (SAI), which involves injecting tiny particles into the upper atmosphere, and marine cloud brightening (MCB), which uses sea salt to stimulate cloud formation over the ocean.
• Solar geoengineering is not a substitute for reducing greenhouse gas emissions, but a possible temporary measure to limit warming while emissions are reduced and carbon dioxide is removed.

What are the benefits of Solar Geoengineering?
• Reducing climate changes around the globe, such as extreme temperatures, changes in water availability, and intensity of tropical storms.
• Offsetting some of the warming from a doubling of CO2.
• Cooling the poles more than the tropics, and thus slowing or stopping ice loss.
• Being affordable and feasible compared to other climate interventions.
• Lowering Earth’s global temperature and offsetting the costs of global warming

What are risks of Solar Geoengineering?
• Shifts in weather patterns and creation of droughts in some regions due to changes in precipitation and atmospheric circulation
• Lower crop yields and hunger due to a less-intense sun, which could affect photosynthesis and plant growth.
• Possibility of catastrophic heat wave across the world if the spraying of aerosols is stopped abruptly, leading to a rapid rise in temperature
• Intensification of ozone depletion due to the interaction of aerosols with stratospheric chemistry.
• Threats to national security and international stability due to the unequal distribution of benefits and harms, as well as the potential for unilateral or rogue actions.
• Challenges related to issues of environmental justice and equity, such as who gets to decide, monitor, and regulate solar geoengineering, and who bears the costs and risks
Source – Washington Post, DTE