View source for Talk:Sea level rise

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== Copy editing, trimming & Migration ==

Hello y'all. Thanks to all who have contributed so much interesting info to this article. Im planning to undertake a little copy edit run to see if the unsightly tag can be removed. I'll likely also do a little trimming. Much as I agree with ITK's arguments, the article does seem too long. No worries if anyone reverts these changes if they don't see them as improvements, especially the trimming, its always unpleasant to remove another editors work.

One change that I do think should remain at least in some form is the update concerning migration. Considering there's a strong possibility of climate migrations numbering between 0.5 – 1.5+ billion souls within the lifetimes of some here, the subject is a little under discussed in the sources. But in the specific case of SLR, [[António Guterres]] spoke about the risk of SLR alone impacting on almost a billion, causing mass migration on a "biblical scale". The good secretary general's warning was widely reported in the media, so does seem to warrant inclusion. [[User:FeydHuxtable|FeydHuxtable]] ([[User talk:FeydHuxtable|talk]]) 15:14, 25 February 2023 (UTC)

:Thank Feyd! Would be great to bring out good the best parts of these recent additions by trimming. For anything as sensitive as migration, do use high quality secondary sources. [[User:Femke (alt)|Femke (alt)]] ([[User talk:Femke (alt)|talk]]) 18:57, 25 February 2023 (UTC)
:: Where do we stand now regarding article length? It strikes me as still a bit too long (66 kB (10944 words) "readable prose size"); perhaps aim to get it to around 50 kB? Just wondering if there are any obvious sections where trimming could be done. Pinging [[User:FeydHuxtable|FeydHuxtable]] [[User:EMsmile|EMsmile]] ([[User talk:EMsmile|talk]]) 12:53, 27 June 2023 (UTC)
::: I've added the template for section sizes to the top of the talk page and it shows that the sections on ''causes'' (particularly the Antarctica section) and on ''regional impacts'' stand out as being rather long (but perhaps that cannot be changed, I am not sure). [[User:EMsmile|EMsmile]] ([[User talk:EMsmile|talk]]) 12:56, 27 June 2023 (UTC)
:::: Agreed, and especialy that the 'section sizes' template should be useful for future trimming. I'd already trimmned all the content I was confident no one would object to, so for now nothing to add to Femke's advise on possible bits to trim. [[User:FeydHuxtable|FeydHuxtable]] ([[User talk:FeydHuxtable|talk]]) 19:36, 3 July 2023 (UTC)
=== What to remove, and what to add ===
So, at this point, we all seem to agree that the article is too large, right? I went for another attempt at condensing the article, and it did get slightly smaller - now at 10778 words. Still, according to [[User:Femke|Femke]], this article needs to be at most exactly 10k words to qualify for Featured - so, we still essentially need trim a thousand words from ''somewhere'' to be in the running.

Looking at the recent revisions, I would say that an easy target is [https://en.wikipedia.org/w/index.php?title=Sea_level_rise&diff=1152256250&oldid=1152090678 this edit] by [[User:Datatada|Datatada]]. No-one appears to have spotted it, but what those sentences describe are the consequences of climate change ''in general'' ("climatic shift") not sea level rise ''specifically''. It's an easy choice to cut it, but shedding those 73 words only brings us ~10% closer to the goal. 

Another choice which should be relatively easy is the last paragraph of Small Island States - the whole, "international mining conglomerates will move in once they are flooded" relies on a single Dutch-language from 1989 (that is, a year before the '''first''' IPCC report!) and considering the spotlight these nations have fought for in the recent summits, it's safe to assume it doesn't represent reality any longer unless proven otherwise. That sheds another 62 words, unless a more recent, credible source can be found which isn't contradicted by a better source.

Unfortunately, it seems like cutting the last ~600 words would require painful decreases of what seems like universally good and valuable data left. Moreover, it raises another question: with the article already past its suggested limits, what kind of material is valuable enough to include, and which one should be left out?

Some notable research/articles from this year, any and all of which may qualify for inclusion.

* [https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2022EF002880 New LiDAR-Based Elevation Model Shows Greatest Increase in Global Coastal Exposure to Flooding to Be Caused by Early-Stage Sea-Level Rise] - this (plus its [https://phys.org/news/2023-01-worst-impacts-sea-earlier.html secondary source] say that sea level rise will cover far more land over the first two metres in the earlier estimates (with less afterwards). This presumably belongs somewhere in "Impacts"?

* [https://www.nature.com/articles/s43247-023-00807-4 Future socioeconomic development along the West African coast forms a larger hazard than sea level rise] - in some ways, it makes the same point the article already does when quoting IPCC report for the African section, but this study is fully BY, and there are some figures which may be really helpful (probably more so than my choice to show several major city coastlines when creating this section last year.)

* [https://www.nature.com/articles/s43247-023-00864-9 Large obliquity-paced Antarctic ice-volume fluctuations suggest melting by atmospheric and ocean warming during late Oligocene] - may fit for past sea level rise section, though the decisions of what research to include and what to exclude there will probably always be a little arbitrary.

* [https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2022EF003225 High-Tide Flooding Along the China Coastline: Past and Future] - could be useful for Aisa section, but it's already quite large. (Moving some of it to regional climate change page might be a good idea eventually, but I'm hesitant to do it now due to often-dubious quality of those, and what appears like their relatively low visibility according to [[Wikipedia:WikiProject Climate change/Popular articles]].)

* [https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2022GL101827 Multistability and Transient Response of the Greenland Ice Sheet to Anthropogenic CO2 Emissions] - definitely has to be featured in the GIS article (along with any number of secondary sources), but the question is whether we have the space for it here as well.

* [https://www.nature.com/articles/s41467-023-36051-9 Future sea-level projections with a coupled atmosphere-ocean-ice-sheet model] - this one is interesting because while its numbers can still give pause, it seems to contradict several earlier papers we have featured extensively and suggests lower Antarctica-driven sea level rise than they do. Including it will likely require relatively long explanation.

* [https://theconversation.com/fearmongering-about-people-fleeing-disasters-is-a-dangerous-and-faulty-narrative-200894 Fearmongering about people fleeing disasters is a dangerous and faulty narrative] - what makes this academic commentary very interesting is the pointed criticism it makes of Guterres' remarks [[User:FeydHuxtable|FeydHuxtable]] added earlier this year, as seen on this talk page. Interestingly, my brief search on the subject turned up mostly paywalled research but also  [https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020EF001965 two] year 2021 [https://academic.oup.com/jeea/article/20/3/1145/6460489 papers], whose estimates of displacement are also notable for being '''much''' lower than Guterres' claims. I feel like we cannot just leave those in place now without some sort of qualification considering the opposition from these reliable sources - but that will again take us further away from the ideal article length.

* And then there is [https://www.frontiersin.org/articles/10.3389/fmars.2022.1024111/full this paper], which has some interesting numbers, but happens to come from Frontiers.

In all, thoughts? [[User:InformationToKnowledge|InformationToKnowledge]] ([[User talk:InformationToKnowledge|talk]]) 17:28, 29 June 2023 (UTC)

:I've mostly stopped editing climate change articles for now, but really excited to see you work towards FA. In terms of word count, the "ideal" is a rough 8k, with some people opposing if it gets over 10,000. So if we can, we may want to condense more. The ideas you have are good, as those old primary sources will defitintely give you trouble at FA level. 
:One key place to cut is the lead. It now stands at 755 words, which means that most paragraphs are too long to comfortably read for somebody with slightly below-average reading skills. Aim for around 500 words, and a Flesh reading ease over 45/50 (now 42 according to readable.com). That way, a larger share of people will be able to read the entire introduction. The first paragraph is too number-heavy. I would cut some things myself, but it seems like some of the information is unique to the lead (the lead should only summarize the article, so this is an issue already at GA level). 
:* I think the difference between accelaration and a normal lagged response is too technical. If we omit this, and just say how much it'll rise, that would make it easier
:* The numbers in the second paragraph come from a primary source (tens/hundreds). Is there a secondary source we can use that says it more concisely
:* The third paragraph is about regional impacts. Yet, the last sentence of the second paragraph talks about individual cities based on a Guardian article. This can be omitted, as it's a bit repetitive to single out cities ánd countries in the lead. 
:* local factors like tides, currents, storms, tectonic effects and land subsidence. -> which are the two most important ones?
:* The statement about migration in the third paragraph does not seem supported by the cited source. The body of the article quotes a non-scientist on migration, and given the controversy around the topic, I do not believe this to be properly supported. You may want to omit, and cite is more robustly in the body
:* Fourth paragraph looks good. 
:For the rest of the article, it's often using less information from sourcing that makes it the text more "professional" / suitable to a lay audience. For instance, I get bored before I read the end of the following: "In the near term, some of the largest displacement is projected to occur in the East Africa region, where at least 750,000 people are likely to be displaced from the coasts between 2020 and 2050. It was also estimated that by 2050, 12 major African cities (Abidjan, Alexandria, Algiers, Cape Town, Casablanca, Dakar, Dar es Salaam, Durban, Lagos, Lomé, Luanda and Maputo) would collectively sustain cumulative damages of USD 65billion for the "moderate" climate change scenario RCP4.5 and USD 86.5billion for the high-emission scenario RCP8.5: the version of the high-emission scenario with additional impacts from high ice sheet instability would involve up to 137.5billion USD in damages. Additional accounting for the "low-probability, high-damage events" may increase aggregate risks to USD 187billion for the "moderate" RCP4.5, USD 206billion for RCP8.5 and USD 397billion under the high-end instability scenario". Can you pick out the most relevant numbers? [[User:Femke|—Femke 🐦]] ([[User talk:Femke|talk]]) 18:24, 29 June 2023 (UTC)

Hello ITK, great to see you're possibly interested in elevating this article to FA class. If you’d like to trim the line with António Guterres's  "biblical scale" quote from the article, I've no objection.
  
That said, the above arguments against the good secretary-general are not even wrong. I listened to the whole of his SLR address to the UN, that's why I came to this article in the first place. At no point did Guterres make a quantitative forecast on migration numbers. So there's no possibility of estimates from 2021 papers  "being '''much''' lower than Guterres' claims". I'd guess the confusion may arise from various disengaged academics misunderstanding   Guterres's metaphor when he said SLR might bring a 'torrent of trouble' to almost a billion people. 'Torrent of trouble' essentially meant disruption to their lives, not forced displacement for almost a billion! That would be ludicrous. It's important to understand that folk like Guterres are informed by the best available mainstream science, and are not going to make fringe claims. It may also be helpful to appreciate Guterres's target audience was UN delegates and other players involved in world governance. Those sort of folk are engaged with practical reality and can be relied on to hear his intended meaning.
Granted, Guterres did speak of SLR threatening a mass exodus on a "biblical scale". But this is entirely inline with mainstream predictions. In biblical times, the earths' population was far lower than today. The dramatic wording connotes disasters affection entire peoples or nations as happened in various Bible stories - which is exactly the expected plight faced by various [[Alliance of Small Island States|low lying island states]]. Changing track a bit, you might benefit from considering the economy of expression in Guterres's words, and how they compare with the long sentence on displacement Femke mentioned above, where the list of dry facts are boring even to an accomplished data scientist.

I see the 'Conversation' source suggests Guterres dramatic rhetoric might worsen anti-migrant sentiment. To clarify, Guterres is not an imbecile. He knows that. He's also in a position to judge the effect his words will have in inspiring action & weakening opposition across the worlds different political constituencies. Not to mention the effect on the political unconscious, and various non instrumental reasons like giving public recognition to the existential threat facing various marginalised peoples. When you hold an office like UN secretary-general, you can't always express yourself in flat, neutral language. Sometimes you have to take actions that are going to have mixed results. To do otherwise would be an abhorrent dereliction of duty. It's doubtful the mid rank academics who wrote that 'Conversation' piece are even capable of understanding such matters. [[The Conversation (website)]] is little more than a [[WP:RSOPINION]] expert blog in this context, not the sort of high quality WP:RS we'd want to set against someone like  Guterres.

For future reference, if you come across an addition of mine you'd like to remove or change, you're welcome to simply go ahead and make the edit. See [[WP:Bebold]]. Unless perhaps it's a very major change, no need to start a talk page section, and definitely no need to ping me. Unless you want to of course. It's just there's a risk of setting me off if I read nonsense like in that source attempting to criticise the good secretary-general. Almost as annoying as seeing an editor trying to diss the Colonel! [[User:FeydHuxtable|FeydHuxtable]] ([[User talk:FeydHuxtable|talk]]) 19:36, 3 July 2023 (UTC)


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== Article title, short description, and lede ==

The short description {{tq|This article is about the current and projected rise in the world's average sea level from climate change. For sea level rise in general, see Past sea level.}}. The focus of this article is affirmed by the lede which begins {{tq|Between 1901 and 2018 …}}.

Given that, IMO, this article should be named ''Sea level rise (current and projected)'' and ''Past sea level'' should be named ''Sea level rise''.

I came to this article looking for general information on sea level rise and found the title very misleading in view of the content. I see there has been discussion around related issues in the archives, but the present state is, at minimum, incoherent. [[User:Humanengr|Humanengr]] ([[User talk:Humanengr|talk]]) 18:00, 11 June 2023 (UTC)
: I have no firm view on this but I think the consensus was that as per [[WP:Commonname]], the term "sea level rise" is mostly used for the currently happening sea level rise, not the one from other geological time scales. So from that perspective, the current naming convention would be fine. [[User:EMsmile|EMsmile]] ([[User talk:EMsmile|talk]]) 09:00, 16 June 2023 (UTC)

== Question about the section on causes ==

The section on causes had the following sub-structure so far:
 Ocean heating
 Antarctica
 Greenland
 Glaciers
 Land water storage

I have changed that now to this as something like "Greenland" is not an actual cause description (and it also makes it easier to jump directly to the section of interest from the table of content):

 Ocean heating
 Changes of Antarctica's ice mass balance
 Greenland ice sheet melting
 Glaciers melting
 Sea ice melting
 Changes to land water storage

Did I get this right and do people agree with this? I wasn't sure about the Antarctica section as it's complicated. Therefore just "Antarctica melting" wouldn't be correct. Is "Changes of Antarctica's ice mass balance" is OK?  Or "Changes to Antarctica's ice mass balance" is better? [[User:EMsmile|EMsmile]] ([[User talk:EMsmile|talk]]) 12:44, 27 June 2023 (UTC)

== Changes to land water storage ==

This content in "Changes to land water storage" is not clear to me, could someone take a look and improve it for more clarity?:

"{{tq|Humans impact how much water is stored on land. Building dams prevents large masses of water from flowing into the sea and therefore increases the storage of water on land. On the other hand, humans extract water from lakes, wetlands and underground reservoirs for food production leading to rising seas.}}"

My questions: the building of dams just temporarily changes how much water flows to the ocean but not once the dam has operated for a while. Or are you referring to evaporation from the dam's surface? Also why does the extraction of water from lakes lead to rising sea levels? For extraction from groundwater I can imagine this but not from lakes? And aren't those amounts rather insignificant compared to the other process, i.e. melting and heating? [[User:EMsmile|EMsmile]] ([[User talk:EMsmile|talk]]) 12:49, 27 June 2023 (UTC)

:Thanks for those comments, which are an excellent demonstration of the need for clear and accurate language. I have edited this section and I hope the new version is clearer. [[User:Ehrenkater|Ehrenkater]] ([[User talk:Ehrenkater|talk]]) 15:45, 27 June 2023 (UTC)
:: Hi Ehrenkater, thanks for trying to help but it's still not clearer for me. The sentences themselves are simple enough but the concepts are not explained properly: Dams hold back water but the system will reach steady state when the dam has been operating for a few years, so it's only during dam ''construction'' that less water reaches the sea, right? Or is the issue more about the evaporation from the dams? Secondly why would extraction from lakes lead to rising seas? I think this section is probably trying to summarise some complex interactions but it's been summarised so much that for a lay person the logic has become lost? [[User:EMsmile|EMsmile]] ([[User talk:EMsmile|talk]]) 08:36, 28 June 2023 (UTC)
::: the current wording is now (marginally clearer than before): {{tq|Human activity impacts how much water is stored on land. [[Dam|Dams]] retain large quantities of water, which is stored on land rather than flowing into the sea (even though the total quantity stored will vary somewhat from time to time). On the other hand, humans extract water from lakes, [[Wetland|wetlands]] and [[Aquifer|underground reservoirs]] for [[Food industry|food production]], which may lead to rising seas.}} [[User:EMsmile|EMsmile]] ([[User talk:EMsmile|talk]]) 08:36, 28 June 2023 (UTC)

== Took out stripe chart ==

[[File:20190708_Stripe_graphic_of_sea_level_change_(1880-2013)_Richard_Selwyn_Jones.png|thumb|A [[Warming stripes|stripe graphic]] assigns ranges of annual sea level measurements to respective colors, with the baseline white color starting in 1880 and darker blues denoting progressively greater sea level rise.<ref name="RSJones_201907082">{{cite web |last1=Jones |first1=Richard Selwyn |date=8 July 2019 |title=One of the most striking trends – over a century of global-average sea level change |url=https://twitter.com/selwynox/status/1148154450672050176 |url-status=live |archive-url=https://web.archive.org/web/20190730041359/https://twitter.com/selwynox/status/1148154450672050176 |archive-date=30 July 2019 |access-date=10 August 2019 |publisher=Richard Selwyn Jones}} ([https://web.archive.org/web/20190730042856/https://pbs.twimg.com/media/D-8Li-5WkAIbEcb?format=jpg&name=large link to image]). For sea level change data, Jones cites {{cite journal |last1=Church |first1=J. A. |last2=White |first2=N. J. |date=September 2011 |title=Sea-Level Rise from the Late 19th to the Early 21st Century |journal=Surv Geophys |publisher=Springer Netherlands |volume=32 |issue=4–5 |pages=585–602 |bibcode=2011SGeo...32..585C |doi=10.1007/s10712-011-9119-1 |s2cid=129765935 |doi-access=free}}</ref>]]
I've removed the strip chart because: I am not sure about this stripe chart, seems like the image was taken from a tweet - gets flagged up as unreliable. Also I think stripe charts work better with temperatures. But perhaps others love it?
[[User:EMsmile|EMsmile]] ([[User talk:EMsmile|talk]]) 07:20, 10 July 2023 (UTC)
:  — This is an example of a [[Warming stripes]] diagram, designed to immediately and intuitively communicate quantitative concepts to non-scientists. They don't just "work better with temperatures" even though that was their first application. Warming stripes are in contrast to line graphs, which make many people's eyes glaze over in perplexity. Warming stripes are "new" (2018-) and there is resistance to anything new; accordingly if your requirement is that editors "love it", then it will fail your test.
: — I'm interested: where was it "flagged up" as "unreliable"? Obviously, being in a tweet does not make it inherently "unreliable". Here, tweet author Richard Selwyn Jones ([https://research.monash.edu/en/persons/richard-selwyn-jones bio]) is a reliable source for basic information, especially since the tweet credits an article in ''Surveys in Geophysics''. —<span style="font-family:Times New Roman;font-size:100%;color:dark blue;background-color:transparent;;">[[User:RCraig09|RCraig09]] ([[User talk:RCraig09|talk]])</span> 16:11, 10 July 2023 (UTC)
[[File:ClimateDashboard-global-sea-levels-graph-20230329-1400px.png|thumb|upright=1.35|Global sea level rise from 1880 onwards (the values are shown as change in sea level in millimeters compared to the 1993-2008 average).<ref>{{Cite web |last=Change |first=NASA Global Climate |title=Sea Level {{!}} NASA Global Climate Change |url=https://climate.nasa.gov/vital-signs/sea-level |access-date=2023-06-27 |website=Climate Change: Vital Signs of the Planet}}</ref>|alt=A graph showing a around 25 cm of sea level rise, based on tidal gauge data.]]
:: It was flagged up by this script as being unreliable: https://en.wikipedia.org/wiki/User:Headbomb/unreliable  That's because the tweet is given as the source. If the journal article was given as the source it wouldn't have been flagged, I guess. Overall, I find this chart takes far too long to understand and to convey the same information that is in the "normal" line chart in the lead (see on the right). I guess you are trying to point out that SLR per year is accelerating? It should be possible to do this in a different way, like plotting the slope of the rise over time. (I know you are a big fan of those stripe charts but not everyone shares your enthousiasm about them (see discussion at climate change talk page [[Talk:Climate change/Archive 92#Main image - climate stripes?|here]])). - Anyhow, what do any of the other page watchers think about this? [[User:EMsmile|EMsmile]] ([[User talk:EMsmile|talk]]) 16:45, 10 July 2023 (UTC)
{{reflist-talk}}

== Maximum possible sea level ==

I came to this page with the question: if all of the ice on earth was to melt, how much would sea level change.  There is a lot of really great information on this page, but if my question is answered I was unable to find that answer.  There is a lot of "if this" and "depending on that" and speculation and guesswork, but it seems like mine is a fairly simple and straightforward question.  Hopefully someone knowledgeable can correct this omission or if it is there, make it somehow more obvious.  Please don't consider this as a nasty criticism so much as a way to make a good page even better.  [[User:FatBear1|FatBear1]] ([[User talk:FatBear1|talk]]) 04:04, 26 September 2023 (UTC)
: I came across a sentence in the [[ice sheet]] article which said it would be 58 m. See here: https://en.wikipedia.org/wiki/Ice_sheet#Antarctic_ice_sheet  If it's not already in the [[sea level rise]] article, it could be added, I guess. Would you like to give that a go? - Oh wait, I see we have this sentence already: "The available fossil fuel on Earth is enough to ultimately melt the entire Antarctic ice sheet, causing about 58 m (190 ft) of sea level rise." Should we make it clearer / more prominent, perhaps also mention it in the lead? [[User:EMsmile|EMsmile]] ([[User talk:EMsmile|talk]]) 07:24, 26 September 2023 (UTC)
::Thank you.  I actually did see that 58 meters in this article, but found it ambiguous as it pertains to the question of ''all'' ice on earth melting.  Should we assume that the last ice on earth will melt off of Antarctica with the final sea level 58 meters above current level?  That might be reasonable, but a novice like me doesn't know that.  Or does it mean that the melting of Antarctic ice will contribute 58 meters to sea level increase, but that other ice sheets will make their own contribution?  
::This is a well researched high quality article and even if I do learn the final answer, I'm not sure I could make the changes in a quality way.  I'm not being lazy or a coward.  I've written and modified many Wikipedia articles that I did know something about or which needed someone to get them started.  If the answer does become clear to me and nobody else will make the change, I will attempt it.  But someone here probably already knows the answer and can do a better job of it than I can.  [[User:FatBear1|FatBear1]] ([[User talk:FatBear1|talk]]) 16:29, 26 September 2023 (UTC)
::: I happened to come across some more content about this in the [[climate apocalypse]] article. There it was written like this: {{tq|As temperatures increase, glaciers and ice sheets melt and the ocean expands which causes a rise in sea levels. Sea levels have risen by about 23 cm since 1880 and are currently rising at around 3.2 mm each year.<ref>{{Cite web |date=2019-02-19 |title=Sea level rise, explained |url=https://www.nationalgeographic.com/environment/global-warming/sea-level-rise/ |access-date=2020-01-02 |website=National Geographic |language=en}}</ref> It is difficult to predict amounts of sea-level rise over the next century, although the ice sheets are melting earlier than predicted which makes a high-end scenario of 2 metres of sea-level rise by 2100 increasingly plausible.<ref>{{Cite web |date=2017-07-12 |title=Sea Level Rise Will Flood Hundreds of Cities in the Near Future |url=https://www.nationalgeographic.com/news/2017/07/sea-level-rise-flood-global-warming-science/ |access-date=2020-01-02 |website=National Geographic News |language=en}}</ref> If the entire Greenland ice sheet were to melt, the world's oceans could rise by '''more than 6 metres'''.<ref name=":5">{{Cite web |title=Global Catastrophic Risks 2018 |url=https://globalchallenges.org/wp-content/uploads/GCF-Annual-report-2018-1.pdf |access-date=2019-12-21 |website=Issuu |language=en}}</ref> In the past, at times when the Earth has been 6°C above the pre-industrial baseline, sea levels were 20 metres higher than today.<ref name=":02">{{Citation |title=Climate Change: What Happens If The World Warms Up By 5°C? |url=https://www.youtube.com/watch?v=qWoiBpfvdx0 |access-date=2019-12-20 |language=en}}</ref>  If all the ice on land and at the poles melted, sea levels would rise by '''more than 65 metres'''.<ref name=":5" /> }} [[User:EMsmile|EMsmile]] ([[User talk:EMsmile|talk]]) 08:25, 18 October 2023 (UTC)
{{reflist-talk}}

== Spring back ==

While I was here and reading about the ice sheets it occurred to me: 10,000 feet of ice resting on Greenland is really heavy and is significantly depressing a large piece of the earth's crust.  When that ice melts, the crust will spring back upwards.  This is a well understood process when glaciers recede, but I think it will be significant in the case of such a large ice sheet as Greenland (or Antarctica).  That upward springing land will displace water and will cause additional sea level rise around the world.  I'm curious if anyone has figured out how to estimate that and how much they think it will be. [[User:FatBear1|FatBear1]] ([[User talk:FatBear1|talk]]) 04:04, 26 September 2023 (UTC)

== Ocean Heat Content Rise Graphic ==
[[File:1955- Ocean heat content - NOAA.svg |thumb |upright=0.8 |More recent graphic]]

Showing a dead link at {79}. There are more up to date graphics out there and the link has migrated to ?  How about changing out the graphic and link to a newer version. [[User:GeoSample|GeoSample]] ([[User talk:GeoSample|talk]]) 16:55, 26 October 2023 (UTC)
: I hope you agree that the graphic at right is a good replacement. —<span style="font-family:Times New Roman;font-size:100%;color:dark blue;background-color:transparent;;">[[User:RCraig09|RCraig09]] ([[User talk:RCraig09|talk]])</span> 17:08, 26 October 2023 (UTC)

== Arguments against causes of sea level rise  ==

i noticed that arguments against the causes of sea level rise are not provided. For the sake of a balanced article, it would be better to add objections to the listed causes, especially man-made causes [[Special:Contributions/105.113.105.228|105.113.105.228]] ([[User talk:105.113.105.228|talk]]) 09:22, 22 November 2023 (UTC)
: Like which ones? With reliable sources please. [[User:EMsmile|EMsmile]] ([[User talk:EMsmile|talk]]) 09:53, 22 November 2023 (UTC)

==Readability edits and taking out older content?==
:I'm going to be working in the coming weeks on the Sea level rise article with a view to making it more readable. (This is part of the research communications project that deals with [[Sustainable Development Goal 13|SDG 13]] (action on [[climate change]]) administered by [[Stockholm Environment Institute]] (SEI) and funded by the Swedish government research council for sustainable development [https://formas.se/en/start-page/about-formas.html Formas]. I've noted the discussion here and in the preceding sections about length. So I'll also try and shorten it, including the lead. I'll do this from a readability rather than substance perspective. So feel free to reverse any deletions that you think remove important material. Comments welcome.[[User:Jonathanlynn|Jonathanlynn]] ([[User talk:Jonathanlynn|talk]]) 11:02, 10 January 2024 (UTC)
::Further to this I've now edited the Observations and Projections sections. I’ve removed some of the material from the “Projections for the 21st century” subsection concerning the reaction to the previous (2013-14) IPCC report AR5. (These are the 2017 University of Melbourne study and the 2017 fourth US national climate assessment. Also the very number-heavy discussion of studies  contrasting with Jim Hansen’s 2016 paper.) This material seems less relevant now that we have the IPCC’s SROCC and AR6 providing an up-to-date assessment of all research. It also struck me as too technical for the article. In the Post 2100 sea level rise subsection I removed the 17-83% range from some of the ranges.
::This does reduce length, but editors who disagree may wish to revert the changes.[[User:Jonathanlynn|Jonathanlynn]] ([[User talk:Jonathanlynn|talk]]) 13:38, 10 January 2024 (UTC)
:::Thanks for the edits. Agree this page should contain the most current and immediately applicable information, but I do feel there is merit to keeping the old information elsewhere, perhaps [[Climate model#History]]. I do wonder if there is merit to a standalone article on the history of sea level rise predictions, alone or together with other climate change-related predictions [https://link.springer.com/article/10.1007/s10640-007-9173-9][https://www.forbes.com/sites/ianpalmer/2023/01/17/a-fresh-reading-of-exxons-predictions-of-global-warming-and-climate-change-from-40-years-ago/], but that's a much longer term step. [[User:Chipmunkdavis|CMD]] ([[User talk:Chipmunkdavis|talk]]) 02:29, 11 January 2024 (UTC)
:::: Interesting question. For now, I've put the text blocks of the older predictions back in at the very end of the article - awaiting consensus on talk page whether this should be deleted completely or moved elsewhere for archiving purposes? @Jonathanlynn: where these the only two text blocks that you cut out? [[User:EMsmile|EMsmile]] ([[User talk:EMsmile|talk]]) 12:10, 12 January 2024 (UTC)
:::::I don't think that was a good idea. Firstly, my impression was that the main issue happened to be with the size of the entire article, so removing material from one section only to place it in another does not really help. Secondly, those predictions aren't really "old" at all when compared to a typical citation in a climate change paper - let alone to the 2000s (and sometimes older still) research which is still cited on its own across far too many articles here. In fact, implying that extensive analytical work as recent as 2020 is something which already needs to be "archived" is really counterproductive in my view.
:::::Now that I am more-or-less done with updating the three ice sheet articles, I decided to simplify the section in a different way, by mentioning the AR5 and AR6 predictions next to each other, and simply mentioning fewer details about the other projections beyond how they differ from the IPCC.
:::::I have also tightened up the parts on both of the Antarctica ice sheets, again based on the work I have been doing. [[User:InformationToKnowledge|InformationToKnowledge]] ([[User talk:InformationToKnowledge|talk]]) 20:10, 13 January 2024 (UTC)
:::::: That sounds like a good solution. (I didn't plan for my new "archive section" to stay for long; it was more of a "parking spot" to put those text block back in which User:Jonthanlynn had taken out. If you found a way of condensing this info without losing content then all the better. Thanks!). [[User:EMsmile|EMsmile]] ([[User talk:EMsmile|talk]]) 21:46, 14 January 2024 (UTC)
:::::::Coming back to the discussions here and elsewhere about length, it seems to me the simplest solution would be to remove the bulk of the very long "Regional impacts" subsection in "Impacts" to a separate article. A much shorter section with a highlight for each region could be retained in this main article to provide readers with immediate regional information and links to where to find more. [[User:Jonathanlynn|Jonathanlynn]] ([[User talk:Jonathanlynn|talk]]) 15:17, 2 February 2024 (UTC)
::::::::(To be clear I'm not proposing to do that myself and will edit that section for readability as part of my overall work on the whole article.) [[User:Jonathanlynn|Jonathanlynn]] ([[User talk:Jonathanlynn|talk]]) 15:20, 2 February 2024 (UTC)
::::::::Well, it's a fair suggestion, but the issue is the same as it was before - a sub-article just for the regional projections will likely languish with very low views and few updates and not be very useful. Moving much of the information to the specific regional pages is more reasonable, but the problem is in their poor state. 
::::::::Most notably, the largest part of Regional impacts is the Asia section, yet [[Climate change in Asia]] does not actually exist - that link redirects you to a fairly poor two-paragraph summary in the actual [[Asia]] article, and then it suggests you either go to [[Category:Climate_change_in_Asia]] (yes, a link to a category as a "Further information" link or to other subarticles, most of which also do not exist (Climate change in [[Southeast Asia]] and [[Central Asia]] links just lead you to single paragraphs in those articles, "Climate change in East Asia" is a disambig for "Climate change in East Asian country" pages and "Climate change in North Asia" is a redirect to [[Climate change in Russia]]). It seems like if we want to move content out of here, actually creating [[Climate change in Asia]] would be a necessary prerequisite. Africa and Europe sections could also do with moves, and [[Climate change in Africa]]/ [[Climate change in Europe]] at least exist, though both are fairly bloated messes.
::::::::TLDR; Someone eventually needs to step up on those regional articles in general and the Asia article in particular. [[User:InformationToKnowledge|InformationToKnowledge]] ([[User talk:InformationToKnowledge|talk]]) 15:48, 2 February 2024 (UTC)
:::::::::Predictably, that "someone" ended up being me. Grumbling aside, we finally '''do''' have [[Climate change in Asia]] article, so there finally ''was'' a space for many of the details in this article! 
:::::::::While I was at it, I did something similar with the Africa section (it helped that [[Climate change in Africa]] got better somewhat, though it is still really not great). Now, this article is finally below 10k words for the first time in forever! Amongst the other things, this also means that a key hurdle to nominating this for FA is gone. [[User:InformationToKnowledge|InformationToKnowledge]] ([[User talk:InformationToKnowledge|talk]]) 09:14, 8 May 2024 (UTC)

== Suggestion to cull content on WAIS ==

I've just made a bold edit and suggestion: let's cut this one and move it to [[West Antarctic Ice Sheet]]  if it's not already there (pinging [[User:InformationToKnowledge]] as they have recently worked and updated the [[West Antarctic Ice Sheet]]: is it OK to condense the WAIS content here a bit and point people to the other article for more info?. I think this is a bit too detailed here, using only primary sources, for this high level article that is already very long:

 ++++++++++
Marine ice cliff instability, a related phenomenon observed in geological records but which has not yet been directly observed, occurs when ice [[Cliff|cliffs]] with heights greater than {{convert|100|m|ft|abbr=on|round=5}} collapse under their own weight once they are no longer [[Buttress|buttressed]] by [[Ice shelf|ice shelves]]. This is thought to create a self-sustaining retreat, where, after an ice cliff collapses, further ice behind it is to the same instability, creating rapid loss of ice on a larger scale than has ever been previously observed. However, this theory  is controversial, has never been directly observed by humans, and is only supported by geological records.<ref>{{Cite journal |last=Wise |first=Matthew G. |last2=Dowdeswell |first2=Julian A. |last3=Jakobsson |first3=Martin |last4=Larter |first4=Robert D. |date=October 2017 |title=Evidence of marine ice-cliff instability in Pine Island Bay from iceberg-keel plough marks |url=https://nora.nerc.ac.uk/id/eprint/514800/1/Nature_final_accepted_ms.pdf |journal=Nature |language=en |volume=550 |issue=7677 |pages=506–510 |doi=10.1038/nature24458 |issn=0028-0836 |archive-url=https://web.archive.org/web/20200506155034/https://nora.nerc.ac.uk/id/eprint/514800/1/Nature_final_accepted_ms.pdf |archive-date=6 May 2020}}</ref> Recent research has highlighted the importance of glacial geometry in preventing or contributing to marine ice cliff instability.<ref>{{cite news |last1=Perkins |first1=Sid |date=June 17, 2021 |title=Collapse may not always be inevitable for marine ice cliffs |url=https://www.sciencenews.org/article/climate-marine-ice-cliffs-sheets-collapse-not-inevitable-sea-level |access-date=9 January 2023 |agency=ScienceNews}}</ref> [[User:EMsmile|EMsmile]] ([[User talk:EMsmile|talk]]) 17:39, 28 April 2024 (UTC)
{{reflist-talk}} [[User:EMsmile|EMsmile]] ([[User talk:EMsmile|talk]]) 17:39, 28 April 2024 (UTC)

== Can we update/replace File:Sea_level_rise_projections_for_the_21st_century.png? ==

[[File:Sea_level_rise_projections_for_the_21st_century.png|50px]] - an editor-created graphic from 2013, whose creator has not been active since 2016. 

Needless to say, it is really dated nowadays. It doesn't look very well either, as it is monochrome and very pale, to the point it's blown up to a disproportionate size in the article just to make it readable.
 
The question is: do we want to have someone like @[[User:RCraig09|RCraig09]] create something similar but with the modern projections, or just ditch it outright in favour of an existing compatibly licensed graphic from one of those other studies? [[User:InformationToKnowledge|InformationToKnowledge]] ([[User talk:InformationToKnowledge|talk]]) 04:30, 26 May 2024 (UTC)

: I remember it was a long time before I encountered a good graphic or data for long-term sea level rise for [[File:1900-2300 Long-term projections of sea level rise.svg|50px]]. If someone knows of a good source summarizing other sources' predictions, that is the kind of chart I could generate. Finding a source is the main task. —<span style="font-family:Times New Roman;font-size:100%;color:dark blue;background-color:transparent;;">[[User:RCraig09|RCraig09]] ([[User talk:RCraig09|talk]])</span> 04:40, 26 May 2024 (UTC)
::{{tq|a good source summarizing other sources' predictions}} <s>So, the IPCC?</s> I get what you mean, and after thinking I would never find it, I think [https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021EF002576 this here] is exactly what you are looking for. Recent (2022), comprehensive (82 projections) and reasonably easy to understand once you get what they mean by "families". (In fact, I'll probably end up rewriting at least one paragraph based on its explanations.) 
::It is also CC-BY, so in theory, we could just use [https://agupubs.onlinelibrary.wiley.com/cms/asset/3ac2e1a4-f3c1-4ae7-8d2a-21f6c994db03/eft21004-fig-0002-m.jpg this figure] directly. I know you would say it's "too techy", but consider what is currently in place. To me, the main issue would be explaining all the acronyms (perhaps write our own explanations for the coloured lines in the ''massive'' empty space in the lower-right corner of the graphic, and leave the rest in place?) Once we deal with this, it should already be a huge improvement over the current graphic. 
::We could also use [https://gmd.copernicus.org/articles/16/7461/2023/gmd-16-7461-2023-f03-web.png this graphic] and/or [https://gmd.copernicus.org/articles/16/7461/2023/gmd-16-7461-2023-f02-web.png this graphic], both of which are [https://gmd.copernicus.org/articles/16/7461/2023/ very recent and CC-BY]. I don't think the first graphic is superior to the 2022 one, but the second one could be really helpful for explaining how sea level rise consists of four main aspects. We could also then move another graphic or two to the lead - if [[Climate change]] has multiple images in the lead, why shouldn't this article? [[User:InformationToKnowledge|InformationToKnowledge]] ([[User talk:InformationToKnowledge|talk]]) 06:22, 26 May 2024 (UTC)

::: Actually, I can't see including any of the three suggested charts in a layman's encyclopedia. "families, based on similarities in methods and data"? "Combining families and thresholds leads to three categories,"? They look like inclusions in a doctoral thesis. A good inclusion criterion on Wikipedia would follow from asking: ''What clear "takeaway" would a layman discover in looking at a chart?'' Here, the immediate solution is simply to remove the outdated chart. A related issue is that skeptics would look upon "82 projections" as proof that "scientists don't agree". —<span style="font-family:Times New Roman;font-size:100%;color:dark blue;background-color:transparent;;">[[User:RCraig09|RCraig09]] ([[User talk:RCraig09|talk]])</span> 00:30, 27 May 2024 (UTC)