Ozone hole: Why Antarctic wildlife is being 'sunburnt’
By: Grace Young
News Article: https://www.bbc.com/news/science-environment-68906013
Research Article: https://onlinelibrary.wiley.com/doi/full/10.1111/gcb.17283
Background:
When ozone reacts with chlorine or bromine radicals in low temperatures they are able to break apart ozone to form oxygen (O2) thus depleting the ozone concentration in the stratosphere. Both anthropogenic and natural processes play a role in the depletion of ozone (1). The stratosphere ozone layer is important for us due to its ability to filter out ultraviolet (UV) radiation from the sun. Depending on the type of UV radiation our ozone will filter out the radiation to different degrees. All UV-C is absorbed, most of UV-B is absorbed and around 50% UV-a is absorbed; with each of these different types of UV radiation having different levels of danger associated (2).
News Article:
The news article is very heavy on quotes from different scientists even starting off with a quote stating that Antarctica wildlife is having an increased exposure to sunrays. We then get a very brief explanation of what ozone is and that there is a hole in the ozone. The article blames wildfire (fueled from climate change) as the major cause for the ozone hole. The readers then are told that ozone depleting chemicals such as primarily CFCs or chlorofluorocarbons are to blame originally for this loss but the Montreal Protocol helped in regulating these chemicals. The author then mention the seasonality of the ozone hole and how it is due to chemical reactions that occur at very low temperature and in high atmospheric clouds. but nothing to any depth. The rest of the article hops around to different wildlife and how those animals are affected from the increased UVs. The news article ends with a call to action for us to reduce our carbon emissions to stop the wildfires which would then prevent the depletion of ozone and allow the ozone hole to heal.
Research Article:
The author's main goal was to highlight the critical threat to Antarctica's ecosystem due to the extended ozone depletion coupled with the reduced ice and snow caps caused because of climate change. The article begins with a quick history lesson about the ozone layer. Chlorine and bromine containing halocarbons as “refrigerants and solvents” are blamed for the loss of ozone in the 1970s. Although there has been a recovery due to the implementation of the Montreal Protocol there are still many factors that could delay the recovery. The authors point out wildfires and volcanic eruptions but also other anthropogenic sources such as stratospheric aerosol injections (geoengineering) and the increased frequency of civilian rocket launches as factors that could delay the recovery of the ozone hole.
The ozone hole generally peaks between September and October. However, since 2019 there have been deviations for the general trends they were seeing. Temperature and the polar vortex play a very key role for the ozone hole and its duration. In 2019 the ozone hole was smaller than normal but also the duration was shorter. Then from 2020 to the present we see the ozone hole having a longer duration. This change is seen to have an effect on the surface radiation exposure seen through the UV index.
Figure 1 Antarctic ozone depletion and maximum ultraviolet radiation index at subtropical and polar locations. (a) The size of the Antarctic ozone hole for 2019–2023 (coloured lines) superimposed on the average value between 2000 and 2018 (black thick line; the shaded area is the standard deviation). The ozone hole is defined as the region where total column ozone is less than 220 Dobson units. From 2019 to 2023, the ozone hole closed on November 9, December 29, 22, 16 and 20, respectively. Data from NASA Ozone Watch (2023). (b) Changes in the maximum UV Index at three locations between the 1970s (pre-ozone hole; thin lines) and the period of maximum ozone depletion (1990–2020; thick lines). Grey lines are in the Northern Hemisphere (light grey: San Diego, California; dark grey: Barrow, Alaska; months are indicated on the top x-axis), while Palmer Station in the Southern Hemisphere is in blue (months are on the bottom x-axis). The light blue filling highlights the large increase in the maximum UV Index observed in Antarctica as a consequence of stratospheric ozone depletion. Each point on the UV Index scale is equivalent to 25 mW m−2 of UV radiation (http://www.bom.gov.au/uv/about_uv_index.shtml). Data are daily counts replotted from Bernhard et al. (2022).
The author then discusses why the higher UV-b radiation impacts the ecosystem. The main issue they discuss here is that this impacts the ocean due to the lessening of ice cover. Without the ice cover the UV-b radiation is able penetrate into the ocean which could affect numerous species in the water. The article admits that most of their knowledge about the impact of UV radiation for Antarctic ecosystems was based on studies from the late 1990s which they recognize can be an issue as it may not represent the situation the ecosystem is in now.
Figure 2 Changes in potential for exposure of Antarctic organisms to UV radiation during spring and summer. Top panel—if peak ozone depletion occurs in early spring (September–October), most Antarctic organisms are protected by sea ice and snow cover. Although the reduced ozone layer meant that more UV-B radiation reached the surface, the overall amount of sunlight was low due to the low solar zenith angle at this time of year. Lower panel—in late spring, snow and ice melt and Antarctic organisms become exposed to sunlight. A late recovery of the ozone hole (November–December) implies that more UV-B radiation reaches Antarctic ecosystems in a period that coincides with peak breeding season for many marine birds, mammals and plants. Some organisms have protective strategies for surviving high UV-B environments that include behavioral changes (e.g., migration towards low UV environments) and the production of protective
Plankton and krill have both been seen to have effects from the radiation. For plankton photosynthesis, respiration, and mortality are negatively affected from the UV-b radiation. Then krill feed off plankton and they have seen an increased mortality rate for them from the UV-b radiation which then has consequences for animals that feed off of the krill. Much of the issues discussed for the rest of the article is other wildlife responses to UV radiation is just coming from what we know from how humans respond to UV radiation. The article points out the lack of research done for these animals on how UV radiation affects them. Much of what the authors point out is that eye damage seems to be what could affect these animals the most. However many of these animals have different mechanisms that could protect them from the harmful radiation. For example magellanic, rockhopper and king penguins all produce oil droplets inside their eyes that could protect the cells from harmful UVs. This can also be seen for the vegetation as well. However the vegetation also are seeing a change in the surface climate due to the ozone hole. Stronger wind jets are now being seen as well as they have shifted position slightly impacting wet and dry zones. This change in surface climate has played a major role in sea-ice retreat thus affecting the vegetation. The author concludes with a call to action about the importance of immediate action to reduce carbon emissions for the global economy.
Analysis and Criticisms of the News Article
Overall the news article is very brief and tries to give a high level overview of the research article. A majority of this news article is quotes from different scientists or pictures of wildlife in Antarctica. Even with lots of quotes from interviews they conducted, they completely miss part of the main idea of the research article. The reduced sea ice cover as a consequence of climate change is not mentioned once. They mention the ozone hole and then discuss how that affects the wildlife but completely skip over the reduced sea ice coverage.
The news article also makes some generalizations that necessarily weren't in the article and could be misleading. For example the title of the article is “Ozone hole: Why Antarctic wildlife is being 'sunburnt’” yet the main risk that is seen is eye damage due to the outer covering many of the animals have. However I think where the news article got that title from may be seen from krill as they reported an increased mortality rate with increased UV radiation. I personally just felt that the title was used as a way to get viewership and draw out a certain emotion for readers.
I believe this news article didn't fully discuss the article and just cherry picked what parts they wanted to talk about so I would give this news article a 4/10 mainly losing points for not discussing a key point of the research article.
Citations
(1) Daniel, J. S., & Reiman, S. (2022). Scenarios and information for policymakers. In Scientific assessment of ozone depletion: 2022. GAW report no. 278. WMO scientific assessment of ozone depletion: 2022 https://ozone.unep.org/sites/default/files/2023-02/Scientific-Assessment-of-Ozone-Depletion-2022.pdf.
(2) World Health Organization. Radiation: Ultraviolet (UV) radiation. www.who.int. https://www.who.int/news-room/questions-and-answers/item/radiation-ultraviolet-(uv).
Grace, thank you for sharing this interesting article and your analysis of it. It is definitely a thought-provoking read! I agree with you that the News article’s title is somewhat misleading, but it does succeed in capturing the audience's attention.
ReplyDeleteI have the following questions:
They mention that “the aerosol injection causes a delay in the recovery of the ozone.” How is that possible? And if that is the case, wouldn’t aerosol injection cause more harm than benefit, and therefore should not be pursued going forward?
In your analysis, you mentioned that “their knowledge about the impact of UV radiation on Antarctic ecosystems was based on studies from the late 1990s,” and in the abstract, they state that previous research on UV impacts in Antarctica tends to be studied in isolation. They claim that this study will consider multiple climate impacts to provide a more comprehensive understanding. However, they do not describe their methodology at all in the paper. The article includes an abstract, introduction, results, and conclusion, but no methods section. How can we evaluate the validity of their findings without understanding their approach?
Additionally, what is special about Antarctica that causes the ozone hole to appear there every spring? Do you know if it is the same in the Arctic region? I know that the Arctic is also warming rapidly and ice loss is faster than ever. But can we extrapolate the results from Antarctica to the Arctic or vice versa (taking into account the differences in timing due to their positions in the northern and southern hemispheres, as well as the differences in ecosystems)?
Hi Frozan, the article just cites aerosol injection as a cause of delay but doesn't go further in depth but when I looked into it essentially aerosols were injected back into space to hopefully deflect sunlight thus cooling the planet. There was evidence that increasing stratospheric sulfate aerosols can substantially cool the planet (volcanic eruptions is what they cited). However it is limited experiments that have been conducted about this so there are so many unknown but it looks like it's not as helpful as they wanted.
DeleteThe paper is a review article as they did not conduct any experiments of their own. In the abstract they do talk about a paper that was decades-old. The authors do state in the paper that most of their knowledge is from 1990s and early 2000s papers which might not be adequate given this is written in 2024. They do seem to contradict themselves a little bit now thinking about it. The study (2015) they were talking about was animals in isolation meaning zoos so I don't know how much you could apply that to wildlife in Antarctica.
What made this special for Antarctica was there were very stable and cold (more than normal) polar vortexes. Both the northern and southern hemispheres will have polar vortexes but I believe the southern hemispheres are probably stronger because of less landmass. Antarctica is significantly colder I believe so I'm not for sure how much we can take what we learn here and apply it to the Arctic.
Thank you Grace for the clarification! Appreciate you taking the time to respond.
DeleteHi Grace, thank you for sharing this article. I found it interesting that the news article chose to exclude mention of "increased frequency of civilian rocket launches" as reason for stratospheric ozone depletion. While the title of the scientific paper focuses on Antarctic biota, their conclusion and abstract frequently mention reduction of the ozone hole through reduction of geoengineering injections, bushfires, and civilian rocket launches. Since this is their call to action, I would have appreciated if they included just a bit more information about this topic, such as why they reduce ozone or mention of a study relating to a prediction/quantification of the effect of these events on ozone reduction. I would have also appreciated if they had included included more explanation for why they chose the data for their review despite the information being from a few years ago and only on biota in non-Antarctic conditions.
ReplyDeleteHi Helen, I completely agree with you. That's why I felt as if the authors of the news article cherry picked information from the research article to fit the narrative they wanted.
DeleteHi Grace! You did a great analysis of comparing this article to the paper. I think that it is quite surprising that the news article didn't include important information about the ice cover melting. It seems that this would enhance the reasoning for the increased UVs. Also, did the news article state that the ecosystem studies were from the 1990s? Would this have made the article seem "weaker" to the audience or "stronger" since the reader is able to trace what data the study is using? I agree that the title can be misleading to the study's main points. Do you think "clickbait" titles are useful for educating a wider audience about these scientific issues, or is it more important to prioritize all the main focuses of the study? You mentioned that the news article cherry-picked what they thought fit in the narrative they were trying to tell. Is there any part of the news article that you think explained a point well or made a point more accessible to a reader?
ReplyDeleteHi Kristen, the direct quote from the article is “most of our knowledge on the impact of UV radiation on Antarctic ecosystems is based on studies from the late 1990s and early 2000s”. When writing my analysis I forgot to include the 2000s. Regardless of when studies are published wherever they get their data from they have to cite it so the reader could track it down. I think using older literature doesn't automatically make the argument weaker, it just opens them up for more questioning. Since the author did point this out themselves I think they were being transparent and I respect that. As for clickbait titles it's hard to say because I understand trying to make the article sound interesting to get readers but they should try to stay close to the article so it's a hard line to judge sometimes. I think what the author did explain about the ozone hole was good. I just wish they went a bit further into depth.
Deletewas a very interesting read. I did not know about the significant role ice plays in UV-B protection. It is disappointing that the news article decided to skip over the role of sea-ice loss. The journal mentions how there is limited information on how animals are affected by UV, but wouldn’t it be similar to how it affects humans? It seems the effects of ice loss would ripple through the food chain: less protection harms phytoplankton, which impacts krill, and eventually reaches humans and other animals as well. These are incredibly important findings, and thus, I agree with your rating of 4/10. I agree the article prioritized viewership over fulfilling its role as a bridge between the scientific community and the general public. You mentioned that the information on UV impacts on Antarctic organisms is from the 90s. What kinds of updated studies do you think would be most valuable now? Do you think that these types of studies could be useful in places where ozone depletion is not as bad?
ReplyDeleteHi Talia, the information is from the 90s to early 2000s as I forgot to add 2000s when writing my analysis. Animals have different protective barriers than humans so it's not necessarily the same. Like their fur or some animals have oils that protect their eyes from the sun. That's why we can't automatically assume they would be affected the same as humans. I think more studies about the vulnerability of organisms or animals would be very important as they are using older studies or studies from animals in zoos. Potentially these studies could be used in places with less ozone depletion but I would think it wouldn't be as useful if climate and other factors in the environment were very similar.
DeleteGreat job Grace! I agree with your assessment of the news article’s clarity and impact, and overall a 4/10 seems fair. While the article succeeds in drawing attention to increased UV exposure and its potential impact on Antarctic wildlife, it misses critical context, especially the role of reduced sea ice, which, as you noted, is important for understanding the full ecological consequences. I really appreciated how you highlighted that omission, as it shows the article lacks depth in conveying the interconnected nature of ozone depletion and climate change. I also agree that the news article may have oversimplified and glossed over certain parts of the research in order to explain certain things which contributes to a misleading title since 'sunburns' are not actually the primary concern for animals in the Antarctic.. My question for you is: how do you think science communication can better balance accessibility and accuracy in topics like this? How can we have easily understood and digestible information presented without the overgeneralization of it.
ReplyDeleteHi Sarea, I understand there has to be generalization sometimes to balance accessibility. However in my opinion generalizations don't necessarily make it easier to learn and if it's not even true then what was the point? There is a very fine line that has to be walked where these generalization help more than they hurt. I think if the news article went more in depth even just a little bit then it would have been much better because then there is more context to the generalization.
DeleteI agree and I appreciate that you took the time to thoughtfully respond to my question. When nuances are lost due to an overgeneralization we might just be hurting those we aim to help.
DeleteHi Grace! I really enjoyed your analysis. I agree that the title of the article is an oversimplification of the issues facing Arctic wildlife and ecosystems, and does not address the key points of the scientific paper. I'm curious about your mention of vegetation and their responses to increased UV radiation. You implied they have similar responses to increased radiation that penguins do, who are able to produce oil droplets in their eyes to protect against excess radiation. Do you know specifically what the responses of the vegetation are, and potentially how those responses might be causing further ecological cascades of negative impact? I can imagine that if plants are producing new compounds to protect themselves it might impact the species who subsist off of them, or alter the chemical composition of bodies of water containing aquatic vegetation. I'm curious because the ways wildlife adapt to climate change are often used as a justification for not reducing emissions, and I would surprised if these adaptations are inconsequential to the ecosystem as a whole. If you have any knowledge of how the adaptations of the animals themselves are also impacting the ecosystem, I would be interested to learn that as well!
ReplyDelete