TAMPA, Fla. (WFLA) — As the impact of climate change accelerates, some scientists are edging closer to supporting what many call a drastic measure.
Earlier this week, 60 scientists published a letter calling for more research into Solar Radiation Management (SRM) – a very controversial process that proposes using tiny reflective particles to block some sunlight, and help cool the Earth. But they did not endorse the use of this technology.
For some, solar geoengineering is an attractive approach because it’s relatively cheap. And science is pretty certain it will work to cool the atmosphere because nature has been doing this for billions of years through volcanoes. A recent example is the massive eruption of Mount Pinatubo in 1991, which cooled the Earth’s average temperature around 1 degree Fahrenheit for a few years.
When there is a powerful volcanic eruption, ash, soot and aerosols are spewed into the upper atmosphere – a layer known as the Stratosphere. These aerosols can last for months or even years before falling back to the ground. They act as reflective particles, blocking out a small portion of the Sun’s rays. This cools the Earth as long as the particles are still suspended.
There is some modest interest in the climate community to mimic the way nature cools the Earth by manually adding tiny reflective particles to the Stratosphere. This proposed process is called Stratospheric Aerosol Injection (SAI). This would be done by designing specialty airplanes to spread these aerosol particles all around the Earth. To be successful the flights would have to be frequent.
As simple as it seems, there are a few major concerns.
First, there would be unintended consequences to the climate but it’s unclear exactly what they would be. However, cooling the global atmosphere would likely cause varying regional impacts making for some winners and some losers. For instance, it may shift a monsoon or cause a drought or a flood. This would have humanitarian and international security implications.
Secondly, some argue that treating the symptoms of global warming through geoengineering would kick the can down the road on addressing the core cause of climate change – greenhouse gas emissions. They argue that time and effort would be better spent just reducing emissions.
Next, because it is relatively inexpensive, theoretically this could be done unilaterally by a nation, corporation, or even a billionaire. One could easily imagine this causing conflict, especially if there was suspicion that geoengineering was causing side effects.
Lastly, once started, SRM would need to continue indefinitely, or at least until emissions stopped and excess concentrations of greenhouse gases were sucked out of the atmosphere. If SRM was abruptly halted for any reason, all of the warming that would have occurred in that period of time SRM was going on, would happen almost instantly. It’s called termination shock and the pace of change would likely prove to be catastrophic.
WFLA’s Chief Meteorologist and Climate Specialist Jeff Berardelli spoke to a climate scientist and Director of NASA Goddard, Dr. Gavin Schmidt. He is wary of this approach, especially because doing it the right way would take long-lasting international cooperation, something that is almost always lacking.
“Doing this on a global scale and sustaining it across regimes, coups, wars, economic growth & decline, and multiple presidential and congressional elections seems to me to be such a big ask, “Schmidt said. “Because when you stop doing geoengineering it all comes rushing back unless you have reduced your emissions in the meantime. And since reducing emissions in the meantime is the point of everybody else’s efforts it seems to me we should be just focusing on reducing emissions”
At the present time, most scientists agree with Schmidt. Last year, a group of scientists published a paper calling for an international agreement to ban solar geoengineering.