Engineering Solar Shade: Should we manipulate the climate?

Researchers believe that the large-scale manipulation of the climate could be our best hope.
Is solar shade a local solution?  Picture Credit: USDA/Flickr
Is solar shade a local solution? Picture Credit: USDA/Flickr

Principles of design and creativity are integrated into every solution conceived by man. When it comes to climate change, solutions include advancements in the production and storage of renewable energy, upcycling, recycling, and simply living with less. But what if design went a step further? Mike Muller, a visiting adjunct professor at the University of Witwatersrand, believes Southern Africa and even the rest of Africa must begin to engineer the climate if we’re to survive the rate of climate change.

Geoengineering is described as the deliberate and large-scale manipulation of the Earth’s climate in order to minimise the effects of climate change caused by increasing levels of greenhouse gases in the atmosphere. Proposals to do this include plans to suck carbon dioxide out of the atmosphere or to release sulphur dioxide (SO2) into the atmosphere to create a global sunshade, in the same way that the ash and sulphurous gases from a volcano shield an area from the sun. According to Muller, the latter needs to be considered for local application if Southern Africa is to avoid long-term effects of the rising temperatures on water resources and agriculture.

“Southern African countries must consider what they can do to protect their interests in the face of growing threats to economies and welfare,” Muller wrote in a foundation essay published on The Conversation.

“So consider the idea of having a giant sunshade over southern Africa. During the recent heatwave, it would have been wonderful. It could have saved lives and there would have been less evaporation from dams, reducing the impact of the current drought. Crops and livestock would have fared better.”

However, shielding the continent from the sun until it cools down is not a quick fix for global warming. A number of critics have slammed geoengineering for the fact that it reduces pressure for action on the cause of the problem – the waste and emissions created by humans. According to an article in Slate Magazine, geoengineering should be researched and built upon for use by future generations but it should not be considered as a substitute for cutting emissions.

“A combination of cutting emissions and solar geoengineering could get us with near certainty to a world in which the amount of warming (the increase in average temperature) is less in 2100 than it is today,” wrote David Keith, a professor of applied physics in Harvard’s School of Engineering and Applied Sciences and professor of public policy in the Harvard Kennedy School.

“Emissions cuts alone cannot achieve this with confidence, because even if we completely stop emissions tomorrow, the inertia of the carbon-climate system will continue to warm the world for years,” he adds.

Muller goes on to say that while creating a global, or local solar shade is feasible, much more research is needed to determine risks associated with releasing SO2 into the atmosphere. He also calls for the design of more benign materials that can be used in the process.

“To make such interventions practical, the region needs local science, focused on meeting local needs. And Western scientists have been reluctant to help develop this capacity,” he adds.

It is clear that intervention is needed. Last year produced record hot temperatures that scientists believe will become the norm in 15 years.