Pumping a steady stream of sunlight-blocking particles into the stratosphere to fight global climate change would leave us with inescapable hazy and white skies such as those found over big cities, according to new research.
“The skies would be whiter/hazier everywhere, including on weekend getaways to the mountains,” study lead author Ben Kravitz of the Carnegie Institution for Science at Stanford University told me in an email today.
“People may or may not notice these changes, as a lot of color perception depends on physiology, context, time of day, etc., but the physical science basis for these changes would be there.”
Kravitz and his colleagues simulated the effect of mimicking volcanic eruptions to cool the climate by constantly filling the stratosphere with sulfate aerosols. The particles block some of the sunlight from reaching the surface, leading to a global cooling effect.
While this happens when big volcanoes erupt, the effect is short-lived because the particles eventually fall out of the sky.
The concept of so-called solar geoengineering is to constantly replenish the particle supply to block two percent of the sun’s light, maintaining the planet-cooling effect. Doing so, according to the study, would make the sky three to five times brighter, as well as whiter. Sunsets would have an afterglow.
In addition to the whiter and hazier skies, the geoengineering approach might also increase global photosynthetic activity since plants grow more efficiently under diffuse light conditions. On the other hand, the effectiveness of solar power could be diminished since less sunlight would reach the panels.
Such a scheme is one possible geoengineering approach proposed to fight climate change in lieu of – or in addition to – curbing greenhouse gas emissions, which continue to rise despite years of international negotiations to hatch a plan to do so.
Kravitz cautions that his results are based on simulations and “models aren’t a perfect proxy for the real world.”
In addition, if we were to choose a geoengineering approach in our efforts to combat climate change, we might go a different route, such as erecting giant artificial trees to suck carbon dioxide out the sky.
All of these approaches, Kravitz adds, are only Band-Aids that can “alleviate some of the consequences of increased greenhouse gas concentrations in the atmosphere … it doesn’t go to the root of actually solving the climate change problem.”
“The only permanent solution to the problem of climate change,” he said, “is to stop emitting CO2.”
The findings are reported June 1 in Geophysical Research Letters.
John Roach is a contributing writer for msnbc.com. To learn more about him, check out his website and follow him on Twitter. For more of our Future of Technology series, watch the featured video below.
