I’m sure that most people have heard of the crisis with the ozone layer, the massive blanket that was once wrapped snugly around our planet that absorbs harmful UVB light. Although the ozone layer was once at full strength, beginning in the 1970s, scientists started to notice that it was rapidly being eaten away by harmful chemicals, fittingly named ozone-depleting substances (ODS). So, what exactly causes this change in the atmosphere, what are we doing to stop it, and what does the future hold for our precious ozone layer?
Ozone itself is a substance that is naturally created in our world. It may seem like it’s some out of world chemical that magically appears in the atmosphere, it is really just the oxygen we breath in, which is O2 meaning it is two oxygen atoms bonded together, with an extra oxygen atom added in. This makes ozone O3, and this extra atom of oxygen makes it great at absorbing UV rays that come in from the sun in the upper atmosphere before it can reach us humans. When ODS are released into the upper atmosphere through harmful aerosols or industrial chemical usage, they easily rip the extra oxygen molecule away from this ozone thereby creating the hole we face today. When this happens, UVB light is no longer absorbed in the upper atmosphere and is now absorbed by the life on Earth. In humans this can cause cancer or skin damage, but it can also kill plants or harm animal life too. These threats make this a pressing issue in our society.
After we identified this issue as a problem as a planet, we took one major step to prevent the issue from getting any worse. This came in the form of the Montreal Protocol. In 1987, the United Nations identified nearly 100 chemicals and products that were ODS, and they created this legislation to control and phase out the usage of these chemicals in the different countries of the world over time. One fun fact about the Montreal Protocol is that it was the only protocol to be ratified by every country in the UN.
So far, this legislation has been pretty successful, but there still may be more concerns on the horizon. In recent years, the ozone hole in the atmosphere has been shrinking pretty consistently. In fact, in 2019, the ozone hole was at the lowest point it had been since its discovery. However, we are only really able to measure how large the hole gets about once per year during the winter months as it is not present all year round. In 2021, when measured, the result was more alarming. The result this year was that the hole had been much larger than the years surrounding it. In order to ensure a healthy planet for the generations to follow, we must not allow small progress to stop us from completing all of our goals.
I find it kind of funny that through all my years of school and learning about the ozone layer, we were never actually told that its 3 oxygen molecules. I think it’s really cool how the extra molecule is what allows it to be so absorbing of UV rays. We definitely need to be more careful universally about what we’re putting into the atmosphere because it’s not exactly something we can “fix” once damaged. I do find it a little relieving that the UN collectively agreed to be more careful. However, I think the importance of this issue has fizzled out over the years, even though the issue is probably much worse today than it was back then. Hopefully we can figure out some ways to be more friendly to our ozone layer 🙂
As a meteorology major, I am loving this blog post! It is very interesting that you chose to explore ozone for your topic this week. I find that the ozone layer can be best described with the analogy of a space heater and its heating via convection. The process by which NASA records data to simulate the current status of the ozone hole around earth is really fascinating. They have a great infographic with 30+ years (1979-2012) of ozone hole observations by satellites (https://aura.gsfc.nasa.gov/ozoneholeposter/). I believe that 3 satellites (sponsored by NASA and NOAA) are currently measuring ozone, whereas in the past this number was smaller. The large size change seen in 2021 (before shrinkage in October) that you bring up was largely due to increased winds and chillier stratospheric temperatures over Antarctica this year. Related to this blog post as well is the fact that scientists can measure ozone depletion by both the area of the ozone hole around earth and also through ozonesondes (weather balloons carrying ozone measuring equipment) as well. Ground-based measurements are carried out too. All of this information collection will hopefully spur increased action to protect our planet, as you say. I really love that you explored this topic and think you did a great job with it. Looking forward to your next post!
I feel like the ozone layer issue isn’t talked about that much (at least I haven’t heard about it much compared to other issues) besides a few mentions every now and then, which is unfortunate. It’s also cool to learn about the Montreal Protocol having unanimous ratification by every country in the UN. That’s the kind of unity that I wish was seen with every other issue plaguing our world. I wonder what rate the ozone hole(s?) are increasing every year and how long we have until it poses a significant threat to the human race. I also wonder if there’s already been a notable rise in cancer or skin damage as a direct consequence of this issue in the past decade or so. Hopefully, we figure this out before it spirals out of our control.