Greenhouse
gases, carbon dioxide in particular, have led to global warming, which have
affected people’s lives significantly: the temperature in summer keeps
increasing, cities at middle latitudes have less and less snow, and glaciers,
snow cover and permafrost keep decreasing in the two poles. Global warming is
not something that people can ignore anymore. Increasing emissions of carbon
dioxide can aggravate ozone hole; as a result, more sunlight will get to the
earth, which causes the temperature to increase; therefore, Arctic sea ice
melts more during summer. Now, the difference of the extent of sea ice gets to
30% between summer and winter time. The thinner of the sea ice is, the less
carbon dioxide will be removed, according to a recent study.
The article
(source from University of Southern Denmark) published in ScienceDaily
discusses their study of how sea ice can help remove carbon dioxide from the
atmosphere. In the article, Dorte Haubjerg Sogaard’s group states that not
only oceans can absorb a huge amount of CO2, but also the ice. They claim that “the
chemical removal of CO2 in sea ice occurs in two phases”. First, CO2 is formed
into calcium carbonate in winter, which is stored deep down in the ocean. When
it gets to summer, CO2 is also needed for the process of calcium carbonate to
dissolve. The key point in this
article is talking about both forming and dissolving sea ice have impacts on
the carbon dioxide in the atmosphere.
Overall, I thought this article brings up a new idea of
the relationship between sea ice and carbon dioxide. The shortcomings in this
article, I think, would be it does not specifically talk about the process of
how calcium carbonate forms and why CO2 would be necessary to the dissolving
process of calcium carbonate. I know the formation of calcium carbonate needs
CO2, but it made me confused that why when sea ice melts and calcium carbonate
dissolves, CO2 is needed. In addition, a new term “frost flowers” appears in
the article. It is defined as
“flower-like ice”, which was formed on the surface of newly formed sea ice in
winter. It states that there is a higher concentration of calcium carbonate in
frost flowers. It would be better if there were more information provided
regarding the reasons.
In the article “The Impact of Lower Sea-ice Extent on Artic
Greenhouse-gas Exchange”
from Nature Climate Change, there is more information about the temperature
on Arctic and CO2 fluxes, as well as methane. Nature Climate Change did provide the information and data in terms
of how CO2 moves around the ocean. However, it does not mention that dissolving
sea ice would help remove CO2 in the atmosphere. I personally think this
article is more creditable.
ScienceDaily article Link:
http://www.sciencedaily.com/releases/2014/09/140922110424.htm
Nature Climate Change article Link:
http://www.lib.umich.edu/articles/details/FETCH-LOGICAL-e771-e2928c3e686390c7efbdfc8a091a1a5b41bf15b6072933431122c405ad91e77a1
(Click “MGet It-Full Text Online” on the up right)
Reading this reminded me about the lecture on the polar vortex. It is interesting how ice can be so important in chemical reactions/storage relating to atmospheric quality.
ReplyDeleteYeah, this was exactly why I thought this article is interesting. But at the same time, it comes with a few questions which are mentioned above.
DeleteDefinitely informative article. I am also wondering about the size of the Arctic sea ice; this type of information may help quantify the vast importance of the topic.
ReplyDeleteI did a research on the size of Arctic sea ice, "On Sept.16, 2012, Arctic sea ice reached its smallest extent ever recorded by satellites at 1.32 million square miles (3.41 million square kilometers). That is about half the size of the average minimum extent from 1981 to 2010."
DeleteI think because the amount of CO2 that can form calcium carbonate in winter is limited, the amount of CO2 that can be removed from the atmosphere will decrease due to reducing the size of ice. That is another reason why the sea ice's ability of removing CO2 is decreasing. (maybe?)
I find this article interesting and I'm also curious about the dissolution of calcium carbonate in summer and why CO2 is needed.
ReplyDeleteIn paper form Nature Climate Change, it's explained as 'During this period, the melting of pure ice and dissolution of the trapped carbonate minerals lead to an undersaturation of pCO2(partial pressure) in surface waters, and thus an uptake of CO2.'
Yeah, I was curious about the same thing. This explanation sounds reasonable, but I do not know how that works exactly. There is one more guess in the comments, forming calcium bicarbonate. Think about if that is possible...
DeleteI think the fact that the article cites more than one source makes it a more credible article than others at first glance. Seeing that there are multiple research groups looking at this topic might also make a reader realize that this topic is more important instead of just a minor issue.
ReplyDeleteI was surprised that when I was trying to find a related peer reviewed in the library, there are a lot of them. Maybe this is not a news, and scientist now are just trying to figure out the mechanism.
DeleteCalcium carbonate can react with CO2 and water and form calcium bicarbonate, which is a water soluble substance. I wonder if this could be part of the reason why CO2 is needed to dissolve calcium carbonate in Arctic summer.
ReplyDeleteThe reaction can be written as: CaCO3 + CO2 + H2O --> Ca(HCO3)2
It is a good guess actually! I thought about it for a while, but the question I would ask is: will calcium bicarbonate change the PH of the sea ice since HCO3 is an acidic group?
DeleteThis was an interesting article, but I wish that they would have touched more upon the implications of the lesser uptake of CO2 in regards to both the ocean and the atmosphere. They mention in the Science Daily article that an increase in CO2 will cause a "major impact on the global carbon cycle," but it would have went into more detail, explaining how they propose it has an impact. It would be interesting to see the effect of decreased CO2 on the ocean and it's inhabitants, as well.
ReplyDeleteThere are much more information in the "Nature Climate Change" article regarding how CO2 moves between atmosphere and ocean if you are interested!
DeleteI was especially interested in the frost flowers and the role they play. I had no idea that the ice itself actually helped with the absorption of CO2. I would like to know more about how the frost flowers work.
ReplyDeleteWhen I was reading the article, I had another question: is there a difference between "old" ice and "new" ice in terms of calcium carbonate concentration?
DeleteIn the article, from my understanding, the process of melting ice in summer absorbs CO2 instead of ice itself. So then, we have the same question...
Looking into frost flowers further, this article: http://epic.awi.de/10567/1/Kal2004a.pdf describes a link between frost flowers' aerosol release and "bromine explosions", connecting back to the blog post a few weeks ago.
ReplyDeleteThis is an interesting article, the Nature review also brings up the issue of several studies which have reported sea ice formation emits some CO2 into the atmosphere. So actually constraining the magnitude of the effect of sea ice on CO2 flux seems to still be an issue that is under investigation. It makes sense that things like first year sea ice and frost flowers (both very briny things) would form more carbonate in their brine layers and these both would melt and move the formed minerals into the ocean more than the multi year ice. I personally am interested in the statement that the snow on top of the ice can cap the fluxes of CO2 caused by the sea ice, This makes me wonder if the preliminary calculations about the amount of CO2 taken up by ice processes is overestimated due to the amount of snow in various environments.
ReplyDeleteI think the Science Daily does a good job of introducing how Arctic sea ice helps to remove carbon dioxide from the atmosphere. I agree that the article has some shortcomings in explaining this process of how calcium carbonate forms, since this is a scientific article. However, I found it interesting that they said this study is relatively new and only recently scientists have realized that sea ice has an impact on CO2. I found this surprising since sea ice is related to glaciers, and glaciers are decreasing at a surprising rate. I thought this would have been a study that has been studied for a while, just like glaciers. I liked that the article brought up "frost flowers," which I never heard of before. This is exposing the public to a scientific term that they may never have heard of before just like "Bromine explosions" brought up in another recent article. I wonder if there is a way for humans to intervene in this process and somehow generate more sea ice to help remove carbon dioxide?
ReplyDeleteThe article mentions that open oceans can absorb large amounts of CO2, and this new discovery that sea ice can also aborb CO2. But does ice absorb more CO2 from the atmosphere than open ocean (per unit surface area)? Im assuming that if you lose ice, you will gain open ocean, and that open ocean will also absorb CO2, which would mitigate the effects of melting ice on atmospheric CO2 (assuming the absorption of CO2 in ice and ocean is relatable). Is then possible that the effect on atmospheric CO2 will be negligible?
ReplyDeleteI think that the articles premise is confusing two separate subjects; the CO2 global warming problem is a separate one to that of the ozone hole. The Ozone hole is created from concentrations of Bromine and Chlorine within the atmosphere, while the global warming phenomenon is a separate issue.
ReplyDelete