Solar radiation management (SRM) Geoengineering

Updated: Aug 29, 2019

Can solar radiation management (SRM) geoengineering be capable of providing a solution to climate change? Aditi C. Thanoo discusses.

29 January 2019

Scientists from the University of the West Indies (UWI), Mona received funding to explore the impacts of solar radiation management (SRM) geoengineering on countries vulnerable to climate change, according to an article published in the Jamaican newspaper, The Gleaner, on Thursday 3rd January 2019. These scientists are among the first in the world to conduct such research as this project is one of eight grants awarded through the Developing World Impacts Modelling Analysis for SRM (DECIMALS) funding.

Caribbean scientists have contributed greatly to the field of climate change as in the case of Professor John Agard and his contribution to the fourth assessment report of the Inter-governmental Panel for Climate Change (IPCC). This DECIMALS funding provided to the team of scientists at UWI Mona will again put Caribbean scientists at the forefront of climate change which threatens small island developing states.

It is predicted that with increased in global temperatures, the Caribbean region can mirror global temperature trends, and rainfall patterns will shift causing a decreased total rainfall leading to drier regions and greater occurrences of drought within the Caribbean. The intensity and frequency hurricanes affecting the region is projected to increase as well. Sea level rise is estimated to increase by 18 – 59 cm by 2100. With these estimated projections, it is expected that biodiversity, agriculture, sun sand & sea tourism, and, in turn, Caribbean livelihoods and economies will all be affected.

This demonstrates the need for research, and the need for solutions to climate change. Solutions can be either ways to mitigate climate change i.e. stop the root cause of climate change - the increasing levels of greenhouse gases - or adapting to the effects of climate change so as to reduce impacts on society and the economy.

So the question then is, can solar radiation management (SRM) geoengineering be capable of providing a solution to climate change?

To be clear, SRM geoengineering does not reduce levels of greenhouse gases in the atmosphere but instead reduces solar radiation, by reflecting sunlight away from Earth. This is done by spraying small reflective particles into the atmosphere which deflect sunlight, hence reducing heat by lowering temperatures. This idea was inspired by the localized reduced temperatures caused by ash etc. after volcanic eruptions. Lowered temperatures would reduce the intensity of droughts and storms, as well as the rate of ice caps melting and sea level rise. There is concern that there can be unintended consequences from the use of technology, such as the effects of the sprayed particles on the ozone layer.

However, if SRM geoengineering works in the intended way and we do manage to reduce solar radiation and temperatures, we may start depending on it as a ‘cheap fix’, so much so that we ignore the root cause of climate change: greenhouse gas emissions. It can encourage fossil fuel industries and countries supportive of such, on a business as usual path.

Following this scenario, what if we continue to emit greenhouse gases, knowing that the warming effect caused by these gases are offset by SRM geoengineering, then the concentration of these gases are increased in our atmospheres until we reach a tipping point where SRM geoengineering falters and can no longer compensate? What happens at such a tipping point? Temperatures changes rapidly and adaptation may not be possible. Of course with a ticking clock set from the warning given by scientists to reduce global temperatures, it begs several questions. How desperate are we? What are we willing to compromise? Can solutions to climate change co-exist? Can geoengineering provide short term relief while countries aim towards reducing greenhouse gas emissions?

In the Caribbean, we depend on the solar radiation for our climate and it influences our environment, our culture and our economy. What is the consequence of adjusting levels of solar radiation in our region? What are the monitor and evaluation methods that can be enforced to ensure optimum incoming solar radiation? This is why research by UWI Mona is important so that we can better understand the implications of options such as SRM geoengineering, particularly in the Caribbean region. Maybe it can be an option whilst we phase out fossil fuels but we just have to ensure we don’t continually depend on a bandage without healing the injury.