Make Sunsets: Towards a more realistic stratospheric solar engineering solution for cooling the Earth using solar-reflecting balloons

Some dismissed it as a stunt. It is not clear if any particles were actually released or even if the balloons made it to the stratosphere. But Make Sunsets’ experiment is significant for crossing a threshold when it comes to a hotly-debated climate solution: solar geoengineering.

The plan was for the balloons, filled with helium and a small amount of sulfur dioxide, to float high into the stratosphere. There they would burst, releasing their load of sun-reflecting sulfur dioxide particles and cooling the Earth.

Solar geoengineering is a frightening yet tantalizing prospect. Techniques such as creating sulfuric acid aerosols in the stratosphere or spraying seawater into marine clouds seem relatively cheap, fast-acting and easy. Computer modelling studies have found that reflecting sunlight could greatly reduce regional temperature and precipitation changes caused by greenhouse gases (S. Tilmes et al. There is an Earth Syst. Dynam. 11, 587–609; 2020. But we have very little evidence on how this would affect weather, agriculture, human health or other living things.

Cirrus cloud thinning: Planned geoengineering to make a warm planet happen by injection of aerosols into the stratosphere

Cirrus cloud thinning targets wispy clouds higher up in the atmosphere, seeding them with aerosol particles in an attempt to thin them, so they trap less heat.

The method with the least research is stratospheric aerosol injection. It involves spraying aerosols – such as sulfur dioxide particles – into the stratosphere, more than 12 miles above the Earth’s surface, to reflect sunlight back into space. It could be done with balloons or specialized airplanes able to fly at high altitude.

The idea is a direct result of volcanos. When Mount Pinatubo erupted in the Philippines in 1991, the sulfur dioxide it expelled high into the atmosphere had the effect of temporarily cooling the planet by 0.5 degrees Celsius (nearly 1 degree Fahrenheit).

The world is on track to pass critical warming thresholds, beyond which the chances of extreme flooding, drought, wildfires and food shortages increase dramatically.

Moon dust could be blown toward the Earth to reduce the amount of sunlight reaching the planet.

I would like there to be no geoengineering. Iseman told CNN in an email that he was the founder of Make Sunsets. He said there were no other realistic options to stay below 2 degrees.

The world needs to cut emissions, and it requires international cooperation, according to David Keith, a Harvard University professor of applied physics and public policy

The world needs to cut emissions, “no question,” David Keith, professor of applied physics and public policy, at Harvard University told CNN. He said that it didn’t mean we could ignore other climate solutions.

There are concerns that fiddling with the planet’s thermostat could affect rain patterns and monsoons, which could be devastating for crops.

“When things go wrong, it is usually the poor people that suffer the most,” said Chukwumerije Okereke, professor of global climate and environmental governance at Alex Ekwueme Federal University in Nigeria.

People are already suggesting African countries as a testing ground for the technologies, Okereke said. Africa should be receiving help from the sort of policies that it is being distracted by.

Solar geoengineering has to be maintained as aerosol particles do not stay in the atmosphere for more than a year. If halted, there is a risk of “termination shock,” unleashing all the pent-up warming “waiting in the wings, ready to slap the Earth in the face,” Raymond Pierrehumbert, professor of physics at Oxford University, told CNN.

It would also require unprecedented international cooperation, Frank Biermann, professor of global sustainability governance at Utrecht University in the Netherlands, told CNN. “It would mean that countries have to collaborate forever,” he said, including those currently at war.

Source: https://www.cnn.com/2023/02/12/world/solar-dimming-geoengineering-climate-solution-intl/index.html

Diversifying global research in geospheric, geoengineering, and geopolitical research: the example of East Africa

In 2019, Congress allocated $4 million to the National Oceanic and Atmospheric Administration for stratospheric research, some of which was for solar geoengineering. And last year, the Biden administration announced a five-year research plan to explore the concept.

The organizations that provide funding for research are also giving. The Degrees Initiative, founded in the UK, will be conducting research in a number of countries across Africa, Asia and South America to find out how technology could affect the Global South.

Second, we must diversify the field to avoid bias. Women are more risk averse than men so a field dominated by men might have overly optimistic framings. Researchers from powerful, well-resourced countries might be more optimistic about agency in global decision-making than those from poorer places.

Without diversity, research won’t be seen as legitimate by everyone. In Europe or North America where the research has been done, you should work to broaden participation in the field geographically and demographically.

Finally, model-based research should reflect geopolitical realities. Current models tend to assume there will be global cooperation, which is difficult to achieve in the real world. Models should instead reflect the likelihood that, without governance, schemes will be uncoordinated and regional.

One of my studies has found that a reversal of a dry spell can cause a dry spell in East Africa. Geophys. Res. Lett. 48, e2021GL093129; 2021). Different research groups should tackle regional possibilities in their own way, because more are needed. The patterns that emerge can inform policy.

Latin American diplomats, civil servants, and research questions: What are they saying about the cosmological constant and how to use it?

I met with a group of diplomats and civil servants in Latin America and the Caribbean last summer and they all seemed to agree with this approach. In turn, these interactions help to generate salient research questions.