Space debris and ozone depletion
Here we go again?
It seems that ozone may be at risk again, from another man-made effect. A new study speculates that space debris from large constellations of new communication satellites could cause the problem.
The theory is that during the fiery re-entry of dying satellites into Earth’s atmosphere, any ablated aluminium will react with oxygen in the upper atmosphere to form oxides that can destroy ozone in cycle of reactions similar to those involved with ozone destruction by chlorine from CFCs. And just like those reactions, the aluminium isn’t consumed in the process. It’s left behind to act again.
Scientific American’s report of the paper was accompanied by this fantastic 30 minute exposure of the night sky.
Those innumerable traces of satellite paths caused by sunlight reflecting off them give you an idea of the magnitude of the problem. And it’s getting bigger all the time.
Apparently the amount of aluminium added to the atmosphere from these dying satellites was about 17 tons in 2022, not yet enough to cause significant ozone depletion. But the authors of the study speculate that it could become problematic for ozone in the event that number of satellites eventually increases by another factor of twenty or so. I’m not sure how likely that is. Time will tell …
Anyway, check the links above for more.
Or take a look at our article about it at The Conversation.
Thanks for article link, worthwhile read as it does decent job of increase seen. Actually the ozone hole would not have formed except for nucleation site for chemistry to happen, in Antarctica I recall that was on primarily Nitric Acid snowflakes which form only in coldest pockets in Antartica. Once first light hit the particles, Ozone got destroyed by a highly efficient catalytic reaction. Susan Solomon hit on the idea at AGU in San Fran when in off time she step into presentation on Polar Stratospheric Clouds. This just after BAS team discovered and timidly published what Rowland would name the Ozone hole. Actually till AAOE expedition in August-September 87 chemistry not certain. On morning of September 16, the NASA U2 penetrated multiple times the interface where ozone was being destroyed and iorn clad proof of CFC mechanism into ozone destruction at 20Km was established. By noon, 1Pm at latest the famous smoking gun plot was produced. At 3PM for reasons never divulged, the US negotiating team reversed its position which was about to sink Montreal Accord. By 6PM the Famous Montreal Accord was signed. I have very strong suspicions who leaked the critical smoking gun plot on 16th to someone with access to US team. Once the team would have seen the plot with someone like Rowland explaining it, they would have known the definitive report would be out in 3 weeks. They had the choice of looking farsighted or unemployable. No wonder US team reversed role. Especially most likely McFarland, DuPonts lead scientist at AAOE in Punta Arenas Chile likely signed the fax with smoking Gun plot. DuPont was by far the primary industry manufacturer of CFCs and McFarland quietly carried huge influence.
Now one thing was Ozone depletion mechanism were vastly underestimated. With incredible more complex chemistry of spacecraft burning up I have not doubt that the 20 fold increase needed to impact ozone will greatly decrease. It will take some type of in-situation measurement to be definitive like it took for the Ozone hole.