Greenland was once actually green, study says. That's an ominous climate change scenario.
Rachel Cooper
for 10/24
News Article: Greenland was once actually green, study says. That's an ominous climate change scenario.
Journal Paper: Deglaciation of northwestern Greenland during Marine Isotope Stage 11
From USA Today, the article “Greenland was once actually green, study says. That's an ominous climate change scenario.” by Doyle Rice was published on July 20, 2023 and aims to summarize the paper “Deglaciation of northwestern Greenland during Marine Isotope Stage 11” published the same day in Science. The news article explains that approximately 400,000 years ago, Greenland’s ice sheet melted and caused a five foot rise in sea level. It claims that at the time, carbon dioxide concentrations in the atmosphere was much lower than it is today at about 280 ppm rather than our current 420 ppm. The article emphasizes this as important to coastal cities. The significance of these findings is emphasized through the inclusion of quotes from Paul Bierman, one of the researchers, and Michael Mann, a meteorologist USA Today consulted about the study.
The article goes on to contextualize the ice-core that was studied as it delves into how this ice core was originally drilled during the Cold War at Camp Century, was preserved until now, and recently analyzed. Rice then discusses the implications of this research. The article explains that the melting will happen over a very long period of time and will create a positive feedback loop, but it is still concerning especially when looking at global sea levels.
In the Science article, the authors report that the upper subglacial sediment (Figure 1) was last exposed to light 416 ± 38 thousand years ago. This value was obtained from combining pIR-IRL (post-infrared infrared-luminescence) data of different grain sizes, and the authors found this measurement to be consistent across many aliquots of the two grain sizes. Clearly, the USA Today article rounded this reported value to 400,000, which I think is reasonable.
Figure 1. Camp Century subglacial sediment. Sample 1059-4 is the upper subglacial sediment. (from Science article)
The paper then discusses how this dating allows them to decay-correct previously measured 26Al/10Be ratios of quartz in the sediment based on when the sediment was exposed. They report a maximum exposure duration of 16,000 years. After comparison with the lower sediment, the maximum duration was updated to 14,000 years. The authors found this to be consistent with the analysis of the sediment composition as the upper and lower segments have very similar compositions. The researchers used ice sheet modeling with many different parameters and reported the ice sheet to have an SLE of 1.4 to 5.5 m (sea level contributions); it seems that this is where the USA Today article acquired the value of five feet (about 1.5 m) of sea level rise. Finally, the authors discussed how this melting was due to moderate warming and that current warming predictions are much higher than then and will therefore likely cause melting of the Greenland ice sheet and higher sea levels.
Overall, I found the USA Today article to be accurate and reasonable in the information it presented, and I think they did emphasize the most important takeaways from the research. I also appreciated the included quotations as they helped reinforce the main points and provided legitimacy. I also think the additional context about the history of the ice core was interesting. However, I was also disappointed in how much of the research was completely left out. They did not mention any of the methods used, the additional 26Al/10Be ratio data, comparisons with the lower layer, and the ice sheet modeling. Even though these may not have as apparent importance to general audiences, I think that they help reinforce the main findings and would show the public how this research is done and updates previous work. Additionally, I do find it annoying that the USA Today article did not actually link the Science article, although it is easy enough to find with the included author name. Since the news article left out so much but was accurate in the values and findings it reported, I would give the news article a 6/10.
I found this article particularly interesting because it deals with data from an ice core drilled decades ago but recently analyzed. I agree that the practice of not linking the corresponding paper is frustrating and limits communication because it makes it more difficult for the reader to dig deeper into topic.
ReplyDeleteHi Katie! I also thought it was interesting that the ice core was drilled so long ago, and I feel like this study really embodies the idea that science and research is always building on itself.
DeleteThis article gives us prompt thinking about the complex interplay of factors affecting sea-level rise, the long-term consequences for coastal cities, and the need for innovative solutions to mitigate and adapt to these challenges. I am curious about how can interdisciplinary collaborations between climate scientists, engineers, and policymakers leverage the ancient Greenlandic history to design novel, sustainable technologies and policies that not only combat sea-level rise but also promote ecological restoration and resilience in the face of contemporary climate challenges?
ReplyDeleteI agree! This is definitely an article that prompts us to consider how we can face the impacts of climate change. Like you said, I think it will really take people from many different spheres of knowledge to come up with and implement real solutions.
DeleteNormally I would not say leaving out the research mentioned was too big a crime, since the article did do a good job of covering the stuff of interest to the general population, but since the scientific article is not public access the news source should be covering more of the actual research. When reading the news article I thought it was interesting and figured anyone who didn't believe the science or wanted a closer look at the actual work could just pop over to the scientific paper, which I agree should be linked, but you need an account. This limits the availability to people who are curious about the science, and as you pointed out a lot of the vital aspects are missing. I am curious if your rating would change if they were covering a more easily accessible article.
ReplyDeleteWhen I originally chose these articles, I didn't realize the study wasn't publicly accessible because I was logged in through the university when I found it. I think if the article was available to everyone, maybe I would care a bit less about the USA Today article leaving information out because you're right, they do cover the information that seems to be the most important, relevant, and interesting to the general public. But I do still think that at least mentioning the rest of the work could provide more context and a sense of legitimacy to the claims, especially since the study is not open access.
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