Scientists all agree that we must dramatically cut emissions of gases such as carbon dioxide. While there are certain measures that can be taken, many of them are long-term projects that will take years to fully develop and implement. Many researchers are turning towards potential solutions that could be rapidly integrated, such as solar geoengineering. This refers to an approach that aims to cool down the planet by reflecting solar radiation back into space. The two main methods currently being researched are marine cloud brightening and stratospheric aerosol injection. However, these methods may pose potential effects that have many concerned. The method involving the release of particles into the air was also thought to require specialized high-altitude vehicles to deploy. However, new research suggests that this method may already be achievable using commercial planes already available on the market.
The New Solar Geoengineering Proposal
Until recently, experts believed the high-altitude craft needed for geoengineering would take at least ten years to assemble. However, a new study has suggested that the hurdles of this hypothetical strategy could be overcome without the need for this technology to be developed. However, the entire concept of geoengineering is still highly debated and considered controversial among climate activists and scientists. Even the authors of the study have warned that much more study would be required before world leaders start to implement this technique.
According to Alistair Duffey, the study’s lead author, “There are huge risks and huge uncertainties that require a concerted effort from the research community to tackle before it would make sense to have any kind of opinion about doing this in the real world.” Reducing our reliance on fossil fuels and greenhouse gas emissions is still the most effective way of dealing with climate change. Furthermore, the majority of the scientific community agrees that solar geoengineering is not a suitable substitute for the reduction of emissions. Yet, as our planet’s temperatures continue to increase, solar geoengineering has started to gain more and more attention.
While certain agreements were put in place in an attempt to curb these emissions, such as the Paris Agreement, leaders around the world have so far failed to meet these targets. Some supporters believe geoengineering may someday become an essential option for cooling the globe, and that academics should continue exploring its potential. However, critics feel that focusing on geoengineering distracts us from focusing on reducing emissions. There is also the concern that certain countries may start experimenting without the consent of the rest of the global community.
The Study Focused On The Technology Required
The focus of the study was not on debating the pros and cons of the proposed project. Rather, it focused on what technology would be required if such a hypothetical scenario arose. The most prevalent technique in geoengineering discussions is usually the solar aerosol injection technique. This technique involves spraying the atmosphere with reflective particles in order to redirect sunlight away from Earth. Some studies have revealed that this technique would be most effective at high altitudes, since the particles have the longest lifespan there. The particles tend to fall out of the air faster at lower altitudes and therefore tend to be less effective.
Previous studies showed that 12.5 miles above the Earth’s surface was the ideal height for spraying the particles. However, this is beyond the altitude of what most existing aircraft can safely fly. This is why researchers assumed that an entirely new fleet of craft would have to be developed en masse to perform this task. However, the new study revealed that it was possible to effectively use geoengineering techniques at a lower altitude. The team ran experiments to compare the effects of aerosols at different times of year, latitudes, and altitudes. They discovered that spraying at low altitudes was most effective closer to the poles. Additionally, they found that spring and summer were the best seasons, since there was more sunlight for the particles to reflect off.
However, they found that low-altitude geoengineering was 35% less effective than high-altitude spraying. Yet, spraying at low altitudes still had a meaningful impact in potentially bringing down temperatures. Thankfully, this is a height that many commercial aircraft can reach. Using simulations, the researchers worked out that spraying 12 million metric tons of reflective particles could bring the global temperature down by 0.6 degrees Celsius.
Read More: $66M Geoengineering Project Aims to Cool Earth by Dimming Sunlight
