Talk:Carbon sequestration

Useful content about sediment?
I think this text block that I have just cut out of blue carbon fits better here. But as I am not 100%, I am copying it to the talk page first:

Sedimentation and blue carbon burial
Organic carbon is only sequestered from the oceanic system if it reaches the sea floor and gets covered by a layer of sediment. Reduced oxygen levels in buried environments mean that tiny bacteria who eat organic matter and respire CO2 cannot decompose the carbon, so it is removed from the system permanently. Organic matter that sinks but is not buried by a sufficiently deep layer of sediment is subject to re-suspension by changing ocean currents, bioturbation by organisms that live in the top layer of marine sediments, and decomposition by heterotrophic bacteria. If any of these processes occur, the organic carbon is released back into the system. Carbon sequestration takes place only if burial rates by sediment are greater than the long term rates of erosion, bioturbation, and decomposition.

Spatial variability in sedimentation
Sedimentation is the rate at which floating or suspended particulate matter sinks and accumulates on the ocean floor. The faster (more energetic) the current, the more sediment it can pick up. As sediment laden currents slow, the particles fall out of suspension and come to rest on the sea floor. In other words, fast currents can carry many heavy grains, while a slow current can pick up only tiny pieces. As one can imagine, different places in the ocean vary drastically when it comes to the amount of suspended sediment and rate of deposition.

Open ocean
The open ocean has very low sedimentation rates because most of the sediments that make it here are carried by the wind. Wind transport accounts for only a small fraction of the total sediment delivery to the oceans. Additionally, there is much less plant and animal life living in the open ocean that could be buried. Therefore, carbon burial rates are relatively slow in the open ocean.

Coastal margins
Coastal margins have high sedimentation rates due to sediment input by rivers, which account for the vast majority of sediment delivery to the ocean. In most cases, sediments are deposited near the river mouth or are transported in the alongshore direction due to wave forcing. In some places sediment falls into submarine canyons and is transported off-shelf, if the canyon is sufficiently large or the shelf is narrow. Coastal margins also contain diverse and plentiful marine species, especially in places that experience periodic upwelling. More marine life combined with higher sedimentation rates on coastal margins creates hotspots for carbon burial.

Submarine canyons
Marine canyons are magnets for sediment because as currents carry sediment on the shelf in the alongshore direction, the path of the current crosses canyons perpendicularly. When the same amount of water flow is suddenly in much deeper water it slows down and deposits sediment. Due to the extreme depositional environment, carbon burial rates in the Nazare Canyon near Portugal are 30 times greater than the adjacent continental slope. This canyon alone accounts for about 0.03% of global terrestrial organic carbon burial in marine sediments. This may not seem like much, but the Nazarre submarine canyon only makes up 0.0001% of the area of the worlds ocean floor. EMsmile (talk) 11:48, 8 February 2023 (UTC)


 * To  I don't think the first paragraph dealing with "sedimentation and blue carbon burial" merits placement in the "carbon sequestration" article for several reasons. The first sentence is rather misleading. It reads "Organic carbon is only sequestered from the oceanic system if it reaches the sea floor and gets covered by a layer of sediment". This is confusing since sediment is composed of both organic and inorganic material. So the logic is flawed. One would need to specify "inorganic" sediment which rarely exists on its own. There is however a more fundamental flaw in the reasoning. Organic carbon is still subject to methanogenesis under anaerobic conditions and thus can escape as methane gas. So the statement about it being permanently sequestered is questionable unless we are talking about super depths with such high pressure that the methane hydrate would not escape back to the atmosphere. How significant blue carbon burial is for sequestration would need to be clearly stated and referenced before going ahead. So I think I would put the section back where it came from. The 4 paragraphs that follow deal mainly with the process of sedimentation in various marine areas and not carbon sequestration per se so I would put these back where they came as well. ASRASR (talk) 23:34, 28 February 2023 (UTC)
 * OK, then we just leave it where it is for now (parked on the talk page). I don't want to move it back to where it came from (blue carbon) because it doesn't fit there either. It goes into too much detail and its not well sourced. Also, I checked in the IPCC AR 6 WG I report and the term "blue carbon burial" is not mentioned there. Marine sediment is included but I didn't find content on the importance of any blue carbon burial so I assume it is not a significant sink at this stage. We could maybe look out to see if there are other publications that explain a bit more about sediment and the potential for burial in the deep ocean floor (if that is of relevance here). EMsmile (talk) 00:21, 1 March 2023 (UTC)

EMsmile (talk) 11:48, 8 February 2023 (UTC)

Lead section - undue weight on artificial methods
I'm concerned that the lead section of this article is heavily weighted towards human intervention, and particularly on deep geologic storage of carbon dioxide. The lead says nothing about the carbon-sequestering value of leaving old growth forests, peatlands, and native grasslands alone. Deep geologic storage of carbon dioxide, which is an expensive and thus-far little-used technology, is mentioned three times:


 * 1) "within carbon capture and storage projects"
 * 2) "Artificial processes have been devised to produce similar effects, including large-scale, artificial capture and sequestration of industrially produced CO2 using subsurface saline aquifers or aging oil fields. Other technologies that work with carbon sequestration include bio-energy with carbon capture and storage, biochar, enhanced weathering, direct air carbon capture and sequestration (DACCS)."
 * 3) "Carbon dioxide that has been removed from the atmosphere can also be stored in the Earth's crust by injecting it into the subsurface"

By rough estimates, anthropogenic carbon removal sequesters 2 gigatons of CO2 per year, including a tiny amount of deep geologic sequestration. Non-anthropogenic processes sequester around 10 times as much. I will add a POV tag to the article as I think this bias in the lead is severe. Clayoquot (talk &#124; contribs) 22:32, 16 April 2023 (UTC)
 * Where do we stand with this now? I noticed that User:Jack4576 removed the tag that Clayoquot had added, in this edit with this edit summary: "there are presently no active NPOV or neutrality discussions on the talk page". Does that mean the issue with the lead has been resolved? EMsmile (talk) 14:15, 14 March 2024 (UTC)
 * I see some of the repetition around DAC has been removed, which is good. However, I don't think the issues with the lead have been resolved. My comment above saying there is nothing about the carbon-sequestering value of leaving old growth forests, peatlands, and native grasslands alone. has not been addressed. The following has also been removed, which makes the lead even less informative about the significance of vegetation:
 * Forests, kelp beds, and other forms of plant life absorb carbon dioxide from the air as they grow, and bind it into biomass. However, these biological stores are considered volatile carbon sinks as the long-term sequestration cannot be guaranteed. For example, natural events, such as wildfires or disease, economic pressures and changing political priorities can result in the sequestered carbon being released back into the atmosphere.
 * Clayoquot (talk &#124; contribs) 16:38, 14 March 2024 (UTC)
 * Hello, I had moved that paragraph today from the lead to the main text as I felt it wasn't a suitable summary. The content about a carbon sink being "volatile" or not was not described in the main text yet. In the lead, this information about it being a volatile carbon sink was confusing to me. It sounded like volatile means not really a carbon sequestration, at least not a long-term one. Do we understand carbon sequestration as storage regardless if long or short-term? Perhaps we could clarify this with a sentence or two in the definition section and then summarise it in the lead. EMsmile (talk) 21:36, 14 March 2024 (UTC)
 * I also plan to move big chunks of this article from the "geologic sequestration" section to the carbon capture and storage article as I think it fits better there. Unless there are objections. EMsmile (talk) 21:37, 14 March 2024 (UTC)
 * Carbon sequestration can be either short or long term. Instead of "volatile" you can just say "impermanent". The points in the section that you removed are important for the lead. "Forests, kelp beds, and other forms of plant life absorb carbon dioxide from the air as they grow, and bind it into biomass" is the most important sentence in the article. One of the most important sentences in the encyclopedia, I would venture to say. Clayoquot (talk &#124; contribs) 00:02, 15 March 2024 (UTC)
 * Feel free to put it back in. Would be good if you could also explain there the issue of permanent versus impermanent. When C sequestration is done as part of CCS then it's meant to be permanent. When C sequestration is done as part of normal photosynthesis then it's not permanent, right? Maybe the issue is that the term "carbon sequestration" is used with different connotations in the biology context (natural carbon cycle) versus the climate change mitigation context (locking away carbon). But I am just guessing.
 * I don't follow you though when you say "One of the most important sentences in the encyclopedia, I would venture to say". How so? Isn't it just a sentence that describes the basics of photosynthesis? "plant life absorbs carbon dioxide from the air as they grow, and bind it into biomass". How is this so special?
 * What about my other suggestions about moving stuff out and trimming the article down (and the edits that I did yesterday). I see it as a high level article that should not go into too much detail for all the different processes, natural or engineered ones. - Pinging User:InformationToKnowledge as I always find it interesting when they critique an article. EMsmile (talk) 09:39, 15 March 2024 (UTC)
 * I put it back in. I don't have the energy for further discussion on this. Clayoquot (talk &#124; contribs) 06:24, 18 March 2024 (UTC)

Example of orange peels removed
I've removed this recently added text block as I felt it was too specific an example and didn't really fit into this kind of high level overview article. Please discuss if you think it really does belong here:

"In 1997-1998, approximately 12,000 tons of orange peels were dumped on degraded land in Costa Rica. In 2013, researchers found the land had more tree biomass, more forest canopy, and richer soil than unfertilized land nearby.  Princeton University ecologist Timothy Treuer remarked "This is one of the only instances I've ever heard of where you can have cost-negative carbon sequestration." " EMsmile (talk) 14:18, 14 August 2023 (UTC) EMsmile (talk) 14:18, 14 August 2023 (UTC)

How to clean up the mess around trees and mitigation
Continued from Wikipedia talk:WikiProject Climate change Chidgk1 (talk) 06:52, 14 May 2024 (UTC)


 * As you can see I have moved the forestry info (except albedo) from carbon sink to here and then excerpted all the forestry info here back there. I am now trying to condense the forestry info which is here. Help and suggestions welcome. Chidgk1 (talk) 07:08, 14 May 2024 (UTC)
 * Also ideas welcome at https://en.wikipedia.org/wiki/Talk:Albedo#What_should_we_add_from_this_article? as that is excerpted Chidgk1 (talk) 08:49, 14 May 2024 (UTC)
 * Following me moving some text from carbon sink to here there is now some deforestation info here. Should all the info about deforestation affect on sequestration be in Deforestation and climate change rather than here? Chidgk1 (talk) 09:17, 18 May 2024 (UTC)
 * I agree with you and have done a bit of work to condense the "forestry" section (this needs further work; I am struggling to establish a logical flow here). But I wouldn't move content to Deforestation and climate change, rather to deforestation or reforestation. See also my concern about that article (Deforestation and climate change) on its talk page. EMsmile (talk) 11:34, 6 June 2024 (UTC)

Quote from IPCC AR6 report removed
I've removed this quote from the IPCC AR6 report as I felt it was too cryptic for our average readers and also digressing into other areas. Could we rather take just the essence of it and say it in our own words? "IPCC AR6 concluded that “Where carefully and appropriately implemented, AFOLU mitigation measures are uniquely positioned to deliver substantial co-benefits and help address many of the wider challenges associated with land management. If AFOLU measures are deployed badly then, when taken together with the increasing need to produce sufficient food, feed, fuel and wood, they may exacerbate trade-offs with the conservation of habitats, adaptation, biodiversity and other services.” " EMsmile (talk) 11:32, 6 June 2024 (UTC)


 * Yes I have not got time at the moment but you are right AFOLU is jargon and food mention is confusing and it needs rewriting - feel free to ping me if I have not done it in a week or two. Chidgk1 (talk) 21:21, 6 June 2024 (UTC)
 * Have made an attempt Chidgk1 (talk) 07:10, 7 June 2024 (UTC)

Should carbon capture and storage be mentioned in the lead?
Perhaps the hatnote mention is enough as otherwise the reader might be confused.

Also should Carbon dioxide removal be mentioned in the lead and if so how? Chidgk1 (talk) 08:32, 29 May 2024 (UTC)

Removed content about concrete
I've removed this textblock about concrete from the "mineral carbonisation" section (a section that I felt was overly long and detailed, and difficult to understand for the layperson reader). In case, this should go back in, or should go into a different Wikipedia article, please advise:

++++++++ Concrete is a promising destination for captured carbon dioxide. Several advantages that concrete offers include, but not limited to: a source of plenty of calcium due to its substantial production all over the world; a thermodynamically stable condition for carbon dioxide to be stored as calcium carbonates; and its long-term capability of storing carbon dioxide as a material widely used in infrastructure. Demolished concrete waste or recycled concrete could be also used aside from newly produced concrete. Studies at HeidelbergCement show that carbon sequestration can turn demolished and recycled concrete into a supplementary cementitious material, which can act as a secondary binder in tandem with Portland cement, in new concrete production. EMsmile (talk) 15:58, 16 July 2024 (UTC) EMsmile (talk) 15:58, 16 July 2024 (UTC)

Better image for the lead?
I think the current image in the lead (see on the right) is not very suitable. I am looking at it and can't figure out what I am looking at. Is this some kind of carbon cycle, where is the CO2 coming in or going. What are those strange yellow bundles at the right. They look like French fries but are meant to symbolise crops, I guess. There are some other schematics in Wikimedia Commons that come up when searching for carbon sequestration, although nothing that immediately convinced me. EMsmile (talk) 16:31, 16 July 2024 (UTC) EMsmile (talk) 16:31, 16 July 2024 (UTC)