Stratosphere is a major part of one of the most important resources of our age – space . It seems we have been slowly dumping toxic metals now polluting it. With space debris being an issue already with how much we are crowding low earth orbit with our satellite constellations; metal aerosols are now another issue to worry about.
A study led by Dan Murphy, Purdue science college, has quantified the amount of metals that have made it into the stratosphere due to spacecrafts and satellites that we have launched up into space. The consequences of this can be quite serious to the ozone layer and climate change in general.
At first, it was thought that these metals in the stratosphere might be a consequence of meteoroids burning up in the atmosphere. But the measurements conducted by this study show that the concentrations are analogous to the concentrations of these metals as used in alloys for spacecraft construction.
Metals in the air
The researchers attached advanced tools to nose cones of planes and collected and analyzed air samples from heights of over 17 kilometers high from the Earth’s surface. The analysis showed multiple metals present in the form of aerosols in the air up there “We are finding this human-made material in what we consider a pristine area of the atmosphere.” said stratosphere expert Dan Cziczo, head of the department of Earth, Atmospheric and Planetary sciences at Purdue Science College.
The metals that the team detected consisted of over 20 elements within the sample, mirroring the ratios that these metals are typically found in spacecraft alloys. On the other hand metals that originate naturally from cosmic dust formed a minor constituent within the sample while metals stemming from spacecrafts such as lithium, aluminum, copper, and lead surpassed them in quantity.
Furthermore, they found that almost 10% of significant sulfuric acid particles were found in conjunction with these spacecraft metal particles instead of being in their free state where they help in the maintenance and upkeep of the ozone layer.
Future implications of Stratosphere pollution
The stratosphere lies above the troposphere and is the second major layer of Earth’s atmosphere. This is the region that constitutes unique thermal characteristics and it is where essential chemical interactions take place that sustain terrestrial life. the stratosphere houses the ozone layer, provides UV protection to the surface and is also where commercial jets fly. But with rocket launches being more common these days, the layer is slowly becoming less and less pristine.
Given the current rate of rocket launches, it is estimated that by 2030, as many as 50,000 additional satellites could be launched into orbit, and more and more are being planned to be launched every day. This means that in the coming decades, as much as 50% of the stratospheric sulfuric acid particles could end up being bonded to these spacecraft reentry metals, causing a stress on the ozone layer.
A Cry for Change
These man-made phenomena of stratosphere pollution might cause faster deterioration of the atmosphere as well as the ozone layer, especially with the accelerated rates at which rockets are being launched to set up satellite constellations. There is already a concern over space debris colliding with equipment and damaging it, and international teams already have to make sure to avoid debris while planning launches. With more and more satellite launches planned into orbit, space will become valuable and rare real estate with possible conflicts over usage.
Human impact on our planet is a lot more significant and complex than we realize, constantly upsetting balances within nature. Conscious efforts have to be taken to make sure more irreversible damage isn’t inflicted onto our home. Efforts like the Montreal Protocol meant to reduce the decline of the ozone layer are not only about protecting a layer of the atmosphere, thereby preserving a portion of the planet, but also about safeguarding the Earth’s biosphere in general to ensure safety and wellbeing of all species that share this planet with us.
Through continued research and protective measures, we can attempt to make up for the damage that our actions have caused this portion of our home planet and try to ensure climatic stability, and leave the planet better for future generations.