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Researchers from the University of Cambridge and the Massachusetts Institute of Technology used a 3D model to explore the impact of rocket launches and re-entries in 2019.

Black carbon particles emitted by rockets are 500 times more efficient at holding heat in the atmosphere than all other sources of soot combined, which results in an enhanced climate effect.

While the study showed that the current loss of ozone due to rockets is small, current growth trends around space tourism show the potential for future ozone loss. The pollutants from rockets and re-entries are harmful to the ozone layer.

The co-author of the study said that the comparison of rocket launches to greenhouse gas and air pollutant emissions from the aircraft industry is incorrect.

"Soot particles from rocket launches have a larger climate effect than aircraft and other Earth bound sources, so there doesn't need to be as many rocket launches as international flights to have a similar impact." We need a discussion amongst experts on the best way to regulate this industry.

In order to calculate the findings, the researchers collected information on the chemicals from the 103 rocket launches that took place in 2019. They used the recent demonstrations by space tourism entrepreneurs to create a scenario of a formidable space tourism industry.

The impact on climate and the ozone layer were explored in a 3D chemistry model.

The team show that warming is caused by soot from a decade of modern rockets. After just three years of additional emissions from space tourism, this more than doubles due to the use of synthetic rubber fuels by Virgin Galactic.

The researchers say that when the soot particles are injected into the upper atmosphere, they have a much greater effect on climate than other soot sources.

Under a scenario of daily or weekly space tourism rocket launches, the impact on the ozone layer threatens to undermine the recovery experienced after the Montreal Protocol was implemented.

The Montreal Protocol is considered to be one of the most successful international environmental policy interventions.

The upper stratosphere is where the impact of rocket emissions will be the most severe, according to the study co-author. Ozone change of this magnitude threatens the progress of ozone recovery.

There is still a lot we need to know about the influence of rocket launch and re-entry emissions on the atmosphere, as well as the future size of the industry and the types and by-products of new fuels.

We can enter the new era of space tourism with our eyes wide open, thanks to this study. The discussion about regulating the environmental impact of the space launch industry needs to begin now so we can minimize harm to the ozone layer.

More information: Robert G. Ryan et al, Impact of Rocket Launch and Space Debris Air Pollutant Emissions on Stratospheric Ozone and Global Climate, Earth's Future (2022). DOI: 10.1029/2021EF002612 Journal information: Earth's Future