- Solar geoengineering is the process of spraying substances into the atmosphere to form reflective aerosols that reflect sunlight back into space.
- This could prevent global temperatures from rising, but local or regional temperatures might continue to rise over the next few years, according to new research.
- It is still not clear what the wider implications of solar geoengineering will be, so it could prove to be a risky way to combat global warming.
- The US National Academies of Sciences, Engineering, and Medicine recommended additional funding for research on this topic.
Imagine a world where some parts of the globe are becoming unbearably hot despite all efforts to reduce greenhouse gas emissions. Some governments may decide to “geoengineer” the planet by injecting substances into the atmosphere to create fine reflective aerosols. This is known as stratospheric Aerosol Injection.
These tiny particles could reflect some sunlight back into space, which would reduce global warming. It could have the same effect as a volcanic eruption like Mount Pinatubo’s 1991 eruption , which chilled the planet by half a degree Celsius over many months . The effects of this eruption could have a wide range of impacts across the globe.
What is the quickest time you can expect to see your local temperatures drop? One year? Five years? Five years? Ten years?
What if the temperature seems to be rising in your area?
It turns out that this is exactly what could occur. Although modeling studies have shown that global temperatures could be stopped from rising further by stratospheric aerosol spray, our research suggests that temperatures may continue to rise locally and regionally over the next few years. This information is crucial for policymakers and the general public to grasp in order to make climate policies fair and based on the best science.
The reasons local temperatures may continue to rise
We explore the possibility that the natural variability of Earth’s climate could obscure the effectiveness of stratospheric aerosol-injection.
Natural climate variability refers only to fluctuations in climate that aren’t driven by humans. The El Nino Southern Oscillation phenomenon is one example of natural climate variation. Many parts of the globe experience more extreme temperatures or cooling during an El Nino year (or its opposite, La Nina). These are unavoidable characteristics of Earth’s climate system.
We examined 10 climate simulations that incorporate stratospheric aerosol injection and calculated the temperature that people would experience over a period of 10 years if enough airsoils were used to keep global temperatures from rising to 1.5 degrees Celsius (2.7 F above preindustrial levels), the U.N. Paris climate accord goal.
We discovered that large portions of the Earth’s population may experience continued warming despite global average temperatures falling. 55% could still be experiencing rising temperatures a decade after stratospheric Aerosol Injection began.
This could happen in some of the richest and most powerful countries around the globe, such as the United States, China and India. Countries most likely to see temperature rise in the future might be the ones that could attempt stratospheric aerosol injecting.
It is still difficult to understand the consequences of actions
There are many ways to modify solar radiation, but experts agree that stratospheric aerosol injection is the most efficient and cost-effective.
The idea is to create tiny, reflective particles in the stratosphere at altitudes between 12-16 miles (20-25 kilometers) – above that of airplanes. Although some stories in science fiction suggest that rockets could be used for this purpose, experts believe that modified aircraft is required to distribute aerosols high enough and consistent enough.
The U.S. will be celebrating its 2021 birthday in 2021. The U.S. National Academies of Sciences, Engineering, and Medicine published a report in 2021 on the topic of solar radiation modification, which includes stratospheric aerosol injecting. A committee made up of scientists, economists and lawyers. This group concluded that the U.S. should finance research on this topic. This was partly because it wasn’t clear what the implications of solar radiation modification are.
This is a serious risk because it’s not clear what could happen if the entire world follows strategies such as stratospheric Aerosol Injection, or if any specific country or organization pursues these interventions.
We believe that research into the possible consequences of stratospheric airsol injection should include studies to study potential changes of crop yields, shifts of global rainfall patterns and changes in key regions of the Earth’s Biosphere like the Amazon Rainforest. We don’t know what will happen to stratospheric Aerosol Injection. This is why it is crucial that research is done on the topic.
To stop climate change, it is essential to reduce emissions
We want to make it clear that we do not advocate for the use of stratospheric aerosol injection.
To avoid uncertainty from solar radiation modification strategies such as stratospheric airsoil injection, the best way to prevent global warming is to address its root cause. This, as demonstrated by numerous scientific studies , requires the aggressive reduction in emissions of carbon dioxide, methane, and other greenhouse gasses into the atmosphere.