Talk:Tipping points in the climate system/GA1

GA Review

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Reviewer: Chiswick Chap (talk · contribs) 09:52, 21 July 2022 (UTC)

Comments

I'll have a go at this one. It's really a timely subject, and it's evident that the article has been carefully and intelligently rewritten. Chiswick Chap (talk) 09:52, 21 July 2022 (UTC)

Lead

• The MoS suggests not citing the lead, unless there's dire need like repeated trouble up there, which I guess there might be on this topic? I do wonder whether we'd not be better always citing the lead, actually, as the absence of little blue numbers does get some IPs started...

  The article has seen some trouble yes, mostly from people wanting to add the latest preprint / conference presentation. Prefer to keep citations, so I can check periodically that it's still based on secondary sourcing. There was some major trouble with a sock a year ago with copyvio and misrepresentation of sources, who gained 40% of authorship. Decided that rewriting for GA was the only way to get the article clean. Femke (talk) 18:24, 21 July 2022 (UTC)

• There are citations of news media up here in the lead not given again in body, implying either "new" material in lead not summarizing the body (contrary to MoS), or redundant citations. And see "References" comments below for use of news sources.

  Have binned two of the Guardian articles. I do like giving some more specialist lay sources like National Geographic. I've double checked that the material is not new in the lede. Femke (talk) 18:24, 21 July 2022 (UTC)

  Thanks. There's still one Guardian ref in the lead, and it's found nowhere else. It's also beside a technical paper...

  Removed Chidgk1 (talk) 14:10, 23 July 2022 (UTC)

• A minor detail, "some tipping points ... like the "West Antarctic and Greenland ice sheets" (etc): the linked objects are physical things, not thresholds. I wonder if we could find some short rewording that would be more accurate? Perhaps add the word "thresholds"?

  Done. Femke (talk) 18:24, 21 July 2022 (UTC)

• "irreversible": this is a matter of timescale, isn't it. "irreversible within a human lifetime" would catch the intended meaning, I suspect, but it's a bit long and clunky. The climate can evidently be cooled, eventually: but the hysteresis involved is extremely damaging. Maybe we can find a way of indicating this, suitably briefly?

  Irreversible in this context means that the tipping goes much faster than the reversal. So if something tips within a year, and reversal takes 50 (still within a human lifetime), it's called irreversible in the context of climate tipping. Only a subset of tipping points are truly irreversible (extinctions related to coral die-off for instance). Will think about wording. Femke (talk) 18:24, 21 July 2022 (UTC)

  Actually "within a human timescale" is mentioned in the body, so it's a matter of taste whether it also goes in the lead.

• Finally, once the other items are done, we need to check that the lead summarizes each of (all 7 of) the article's chapters ('Tipping elements', 'Mathematical theory', 'Cascading tipping points', ... 'Social tipping points) briefly.

Definition

• It can be brought about by a small disturbance causing a disproportionately large change in the system." Perhaps this could be worded better; it's not obvious that it adds anything to the IPCC definition.

  It's a different way of saying something similar, yes. I would like to keep it in there, to introduce the word 'disturbance' and 'disproportionately'. Femke (talk) 11:38, 24 July 2022 (UTC)

• I've no idea what an "impact tipping point" is, but since the article is about the "climate system", perhaps the last sentence is simply off-topic?

  Done. Femke (talk) 11:38, 24 July 2022 (UTC)

Geological record

• First sentence could be reworded more directly: "The geological record indicates ancient tipping points..."

  I changed the sentence in the lead somewhat but am not sure how certain the scientists are that there were ancient tipping points - perhaps Femke knows Chidgk1 (talk) 14:52, 23 July 2022 (UTC)

  Femke ? Chiswick Chap (talk) 11:43, 24 July 2022 (UTC)

  rewrote as The geological record shows that there have been abrupt changes the climate system that indicate ancient tipping points. Femke (talk) 11:51, 24 July 2022 (UTC)

Tipping elements

• First sentence singular/plural "a large set of elements" ... "a tipping point". Perhaps "many elements ... tipping points"?

  Done Chidgk1 (talk) 12:45, 21 July 2022 (UTC)

• "20 years ago" is a hostage to Old Father Time. Date please.

  Done. Femke (talk) 17:46, 22 July 2022 (UTC)

• "like the ice sheets": same issue as in Lead section.

  Done. Femke (talk) 17:46, 22 July 2022 (UTC)

Shutdown of the AMOC

• By the way, how does the melting of continental ice warm up surface sea water? Readers might not find this intuitively obvious.

  Readers would be right if they find this unintuitive, as it was wrong. Global warming heat the surface water, not the melting of ice. Corrected that and another minor point. Femke (talk) 18:14, 22 July 2022 (UTC)

WAIS disintegration

• Paleo record redlink is surprising. Is this not Paleoclimatology?

  Done. Femke (talk) 19:02, 21 July 2022 (UTC)

• Guess we'd better link Carbon dioxide here.

  Done. Femke (talk) 19:02, 21 July 2022 (UTC)

Greenland ice sheet disintegration

• "Surface melting reduced" -> "is reducing" or "reduces"?

  Done. Femke (talk) 19:02, 21 July 2022 (UTC)

Amazon rainforest dieback

• "two times" -> "twice"

  Done. Femke (talk) 19:02, 21 July 2022 (UTC)

• "may die" -> "will die"

  Done. Femke (talk) 19:02, 21 July 2022 (UTC)

• We don't really need define the acronym CSD for use just once in the next sentence. Please reword.

  Done. Femke (talk) 19:02, 21 July 2022 (UTC)

Permafrost

• "at least two years": well, that might be a valid definition, but it's wildly misleading for the circumpolar permafrost, which has been around for thousands of years. Suggest we describe the situation rather than giving a dictionary definition.

  Done. I couldn't put my finger on why this sounded weird. Femke (talk) 09:52, 23 July 2022 (UTC)

• "than is present Earth's atmosphere": add "in".

  Done. Femke (talk) 09:52, 23 July 2022 (UTC)

• Link methane.

  Done. Femke (talk) 09:52, 23 July 2022 (UTC)

Coral reef die-off

• Link coral reef and perhaps coral.
• Done. Femke (talk) 09:52, 23 July 2022 (UTC)

Mathematical theory

• "bifurcation with hysteresis, which is": is actually ambiguous, the def. could apply to hysteresis as intended, or to bifurcation-with-hysteresis. I think we're missing a brief def. of bifurcation here. Indeed a diagram might be useful as these are key concepts for the article.

  Rewritten. Have moved hysteresis down to bifurcation-induced tipping, even if I suspect it's part of rate-induced tipping too (will move it back up if I can find a source that says this). Femke (talk) 14:29, 23 July 2022 (UTC)

• "a dangerous bifurcation, or fork" – this is a late definition; if we need to say "or fork" then please move it to the initial paragraph, which is indeed missing a definition as above – but I think the definition needs to be somewhat more detailed than "fork".

  I've tweaked the definition. Let me know if that works. Femke (talk) 14:29, 23 July 2022 (UTC)

• "skewness and tailedness (kurtosis) of time series of relevant variables, with asymmetries in the distributions of anomalies" – well, we're certainly deep into Vulcan-speak here. What variables? What anomalies? There are unknowns piled on unknowns here for the average reader. Could we have a diagram showing skewed and unskewed curves for the general reader? It'd make things much simpler.

  I'm not sure if a diagram of a skewed distribution is DUE. Have asked colleagues working on tipping points to supply more general figures about the three types of tipping points, which is the main thing I want readers to get away from this. Femke (talk) 14:29, 23 July 2022 (UTC)

  Femke, are we still awaiting one figure then? Chiswick Chap (talk) 11:04, 24 July 2022 (UTC)

  My colleague said they'd have a look tomorrow. Femke (talk) 11:32, 24 July 2022 (UTC)

• "This refers to transitions from one state to another" – please don't begin a section by alluding to the title, and please don't use "refers to" in a definition, either.

  Done. Femke (talk) 14:29, 23 July 2022 (UTC)

• "This aspect of tipping assumes" – again, please don't begin by alluding to the section title; and "assumes" should be attributed to a human, not to an inanimate concept. Please begin with a simple definition.

  Done. Should be simpler now + added an example. Femke (talk) 14:29, 23 July 2022 (UTC)

Hope the section is easier to understand now. Found a good source that explains this is simpler terms. I do think it's inevitable that this section is more difficult than the rest of the article, and that people with less affinity for maths would skip over it. But let me know if I missed more opportunities to make it simpler. Femke (talk) 14:29, 23 July 2022 (UTC)

Nearly there ...

Cascading tipping points

• "Crossing a threshold in one part of the climate system may trigger another tipping element to tip into a new state. These are called cascading tipping points." What does "These" denote? Perhaps "Such sequences of thresholds are called..."?

  Done Chidgk1 (talk) 15:13, 23 July 2022 (UTC)

• Domino effects: is this not just another name for cascading? Maybe begin by defining both terms in paragraph 1; then use them if needed. Perhaps "also called domino effects" is what is required.

  Done Chidgk1 (talk) 15:13, 23 July 2022 (UTC)

• Last sentence "The authors point out ... pressures." doesn't actually mention cascading at all: it seems to be a more general conclusion, repeating what has already been said in other sections.

  Well spotted. The paper was not about cascading tipping poitns, but cascading impacts. Moved to impacts section + rewritten. Femke (talk) 18:03, 23 July 2022 (UTC)

Impacts and concern

• Rather a weak title: it's undesirable to have "and" in a heading, as it indicates the random yoking of disparate subjects. We could ask why "concern" is here at all in an article about physical effects and mathematical models; if social awareness (paragraph 3) of tipping points is considered important, then it should have a section to itself, and it should be broadened to cover more than just an Ipsos Mori survey.

  I've removed the concern paragraph. Was weakly against adding it in the first place. Femke (talk) 17:40, 23 July 2022 (UTC)

Runaway greenhouse effect

• "The runaway greenhouse effect is a greenhouse effect": maybe reword?

  Done Chidgk1 (talk) 11:56, 21 July 2022 (UTC)

Social tipping points and climate models

• Well this isn't a great section heading either. Perhaps the "concern" paragraph in "Impacts and concern" belongs down here, too. I think the drift of the section, and the title that it should have, on the model of "Coral reef die-off [as a factor influencing tipping points in the climate system]" etc, is simply "Human behaviour" [as a factor influencing tipping points in the climate system]. In which case, we could wonder whether "Human behaviour" should not simply be one of the "Tipping elements" of chapter 3? I guess the argument for having a separate chapter is that "Tipping points in human behaviour can have both positive and negative effects, contrasting with the normally negative connotation associated with climate tipping points." ... so we would logically have a separate chapter; that in turn raises the question, how many "Human behaviour" tipping points are there, surely more than one? Perhaps we're missing a list of subsections here?

  Trying to think of an example of a positive tipping point - would increasing rooftop solar (in Australia?) count? Chidgk1 (talk) 16:42, 23 July 2022 (UTC)

  Clearly the example should be reliably stated to be a positive tipping point. Chiswick Chap (talk) 16:59, 23 July 2022 (UTC)

  I think having this as a separate section is best because of the positive as you say, but not sure social tipping point theory is mature enough for subsections - again Femke probably knows better than me - perhaps she did not cite the Lenton et al paper I just added because of being at same uni Chidgk1 (talk) 17:27, 23 July 2022 (UTC)

  The examples I've heard most of regarding positive (social) tipping points are more on the innovation-deployment side indeed, so uptake of solar panels and electric vehicles, both of which have become cheaper by learning-by-doing. (see this 2022 paper).

  I'm not quite sure what to do with this section to be honest. There are different definitions of climate system, most excluding humans, but a significant minority including it. If we say section 3 is about the physical climate system, tipping points in a different domain impacting the physical tipping points should be separate? Femke (talk) 17:31, 23 July 2022 (UTC)

  I'd be inclined to make it the last subsection of section 3, perhaps leading into it with a sentence saying this is a weirdo case (choose encyclopedic language) because a, b, and c.

  I have wikilinked Tipping point (sociology) - so perhaps this article has enough social stuff now that people who want more can click through? Chidgk1 (talk) 17:47, 23 July 2022 (UTC)

  Femke ? Chiswick Chap (talk) 10:40, 24 July 2022 (UTC)

  I'm reading through the cited sources to see what terminology they use. The main citation in that section is Franzke et al, which seems to use the words tipping elements as a shorthand for Earth system tipping elements or physical typical elements. I do not know to what extent that is done on purpose, but I don't feel comfortable adding this. In general, I would rather consense this section further instead of expanding it with subsections.. Femke (talk) 10:54, 24 July 2022 (UTC)

  Ok, no subsections, so choice is, I think, a bit more detail or move to main list of tipping points. Chiswick Chap (talk) 11:02, 24 July 2022 (UTC)

  Have expanded slightly. Not an expert but I agree with Femke that the section should not be expanded further. I don't think we know enough to add more. I speculate that politics have changed so much since oil and natural gas prices shot up earlier this year that academics have not had enough time to integrate stuff like the politics of fuel prices into our subject here. Chidgk1 (talk) 06:46, 25 July 2022 (UTC)

General issues

• Infographic image labels are too small to read, suggest scaling all four infographic/map images up a bit. This is an issue where intelligibility relies on reading text within an image.

  Done. The last one is still not really readable, even at upright=1.7. It's already quite obtrusive at that size, so I'm hesitant to make it bigger. Femke (talk) 16:25, 21 July 2022 (UTC)

  Yes. It's also a JPG, so expanding it actually doesn't improve the text beyond a certain point, and the world map (an infographic within an infographic...hmm) is downright fuzzy. It would be much nicer to convert the whole thing to an SVG (scalable vector graphics), or perhaps to a table with an image for the merged central cells... but this is beyond the GA criteria. The best that can be done with the current JPG would be |center|upright=3 and at least readers would be able to make out most of it. If anyone complains you can a) blame me, and b) point out that it represents an entire table with 2 diagrams...

  Increased to 2.5. With upright=3 the image starts interfering with the layout of the references. Femke (talk) 17:46, 22 July 2022 (UTC)

  Just about bearable. with |center|... the image doesn't run down at all, it's fixed in the text. Try it sometime!

• Lead image readability is further impeded by the dark background of some of the image labels, eg "Melt of Greenland Ice-Sheet" is black on dark blue; and the text is very small compared to the size of the image. If you like I can tweak the SVG.

  I asked the original uploader a few days back, and he's started playing around with this. Femke (talk) 16:25, 21 July 2022 (UTC)

  I've tweaked it in a way that seems to help; feel free to try something else if you prefer. Chiswick Chap (talk) 11:03, 24 July 2022 (UTC)

• Fahrenheit is given as well as Celsius in one place. I guess we'd better do that everywhere (using the Convert template) or nowhere. If you're headed for FAC, everywhere had better be your choice.

  Not planning to go for FAC, so I've omitted the unit that, in my humble opinion, should be deprecated. In term of policy compliance, I could argue that this is a scientific article, so I have the choice of omitting US units. Femke (talk) 16:25, 21 July 2022 (UTC)

• Most of the article seems to be in British English. However American "meters" occurs. Suggest we tag "Use British English" and spell "metres".

  Done. Femke (talk) 16:25, 21 July 2022 (UTC)

• Sorry, one more: several acronyms are introduced but never used again. SCC is used only in the sentence where it's introduced. G20 is used once but not linked. GCA and IAM are defined but never used. DICE, FUND, and REMIND are mentioned but neither linked nor spelt out.

  Done - but not sure if I have gone too far by deleting the example models Chidgk1 (talk) 13:41, 23 July 2022 (UTC)

  Well, it's a possible solution but rather drastic; glossing them would certainly be better.

  Femke will know better than me whether these models are important enough be named or not Chidgk1 (talk) 15:17, 23 July 2022 (UTC)

  I agree with deleting the examples, to reduce the weight on that study. Femke (talk) 16:27, 23 July 2022 (UTC)

References

• There are several uses of "cite web" for news sources - the article cites The Guardian which is a newspaper ("cite news" would be right), several times, and National Geographic, which is a magazine as well as a website. All three sources are a bit iffy for a science (and maths) article. I'd remove all of them; if the material needs support, we should repeat the IPCC or other major sources.

  Changed Guardian to "cite news" in case you guys decide to keep it Chidgk1 (talk) 15:32, 23 July 2022 (UTC)

  I've done another pass over the article to remove, replace or supplement lay sources. The remaining are either supplementing scientific sources (which is fine), cited for basics, or giving a quote that I don't want to put in wikivoice (existential threat to civilisation). It's mentioned in the Nature comment by Lenton too. Femke (talk) 10:30, 24 July 2022 (UTC)

• Why is Carbon Brief a reliable source?

  Website seems to indicate it has editorial oversigh, they have a habit of issuing corrections when needed and they've won journalistic awards for their reporting. It's one of the best journalistic sources on climate I'm aware of; one of their articles was even rewritten as a highly cited paper. I've mostly used it in combination with a scientific source, or for really basic science. I'm going to add a peer-reviewed source to the West-Antarctic Ice Sheet one, as I believe this is slightly less forward basic science. Femke (talk) 17:46, 22 July 2022 (UTC)

• BBC Sky at Night Magazine is a very light source here. It'll be reasonably reliable for simple statements but it's hard to think it adds anything to the scientific sources.

  I didn't see where in the NASA cite it says what the runaway greenhouse effect is, so I think this should remain. Have not watched program for decades but it was pretty well respected - still has 2 academics I see https://www.bbc.co.uk/programmes/profiles/1fJ6CZpc1ySM0ZPytwWlW3x/meet-the-team. Chidgk1 (talk) 14:03, 23 July 2022 (UTC)

• There are empty parameters for first=, last= in Shutdown of the Atlantic Meridional Overturning Circulation.

  Citation formatting is not my favourite thing, and not part of the GA criteria. Okay if I don't do these? Femke (talk) 17:46, 22 July 2022 (UTC)

  I must try that on my reviewers! They always argue that the whole MoS and all of its relations are indirectly included (hmm). I'll do a bit of "minor" tidying. Chiswick Chap (talk) 17:56, 22 July 2022 (UTC)

  I think a lot of experienced reviewers are a bit too strict in their GA reviews about MOS compliance and citation formatting. The criteria are really lax on citation formatting: Dead links are considered verifiable only if the link is not a bare url. Using consistent formatting or including every element of the bibliographic material is not required, although, in practice, enough information must be supplied that the reviewer is able to identify the source..

  The criteria are also lax on inline citations, which needs to change, as I don't know any reviewer that reviews according to those low standards. Femke (talk) 18:12, 22 July 2022 (UTC)

  Yes.

• I don't see why we need "language=en" or "language=EN-US" or "language=English" for British or American sources.

  I regularly remove these, but this comments has made me think about why these are included as default in automatic citations. I think it's for translations; reviewers have asked me to include this during a "FAC" on nlwiki if I recall correctly. Not sure why engvar is relevant, but it's invisible anyway. Femke (talk) 17:46, 22 July 2022 (UTC)

  Again, I may do a bit of minor surgery. Chiswick Chap (talk) 17:56, 22 July 2022 (UTC)

• Since this seems to be British English, could we standardise on "date=1 January 2001" format, there are dates in several different formats right now.

  The magic template on the top of the article takes care of this. Femke (talk) 17:46, 22 July 2022 (UTC)

Summary

This is a well-written and informative article, intelligently organised and providing generally good coverage. Once the issues are addressed it will make a worthy Good Article. Chiswick Chap (talk) 11:28, 21 July 2022 (UTC)

Thanks for your thorough review and your kinds words :). Hope to answer everything in the next couple of days, but health is fluctuating, so may take up to two weeks. Femke (talk) 16:27, 21 July 2022 (UTC)

That's fine, let me know if you need more time. Chiswick Chap (talk) 17:04, 21 July 2022 (UTC)

There are two items remaining, both partially-addressed. Chiswick Chap (talk) 08:11, 25 July 2022 (UTC)

Sorry I don't know enough to deal with the "irreversibility" item. Probably better for Femke to do "lead" as well as she would better know the relative importance of the body sections. However if she is not available within a week or 2 ping me and I will have a go. Meanwhile I will do a few small copyedits Chidgk1 (talk) 12:41, 25 July 2022 (UTC)

Femke? Really the main thing left is to adjust the lead to summarize the article decently. Chiswick Chap (talk) 12:37, 25 July 2022 (UTC)

I'm not convinced the new text quite meets the GA criteria. Having minor concerns with accuracy, weasel words, source quality and possibly neutrality. Happy to bring the last two sections to the talk page and work on it outside of the GAN. Don't think it's needed for broadness as it's mainly there to provide a broader context. Femke (talk) 19:42, 25 July 2022 (UTC)

Agree. Apart from anything else, the reviewer is not expected to chase a moving target, and indeed instability is a valid reason to fail a GAN, which would be a pity at this stage. Moved 'Policy' to talk page, if you want to move the previous section too (?) then feel free; I've de-weaseled it a bit. Chiswick Chap (talk) 19:49, 25 July 2022 (UTC)

Femke: can you expand the lead? Chiswick Chap (talk) 19:49, 25 July 2022 (UTC)

I've expanded the lead. I've done so based on length of section (so giving multiple sentences for large section and leaving out one tiny section). I've moved the section on social tipping points to talk and explained my concerns with the text. It was likely the weakest section in the article to start with, and while the new edits resolved some of its defects, it introduced new ones. Femke (talk) 16:12, 26 July 2022 (UTC)

Super, it's a GA. Thanks everybody! I hope you're pleased with the result. Chiswick Chap (talk) 17:32, 26 July 2022 (UTC)

Lovely working with you :). Article has improved a lot. Femke (talk) 17:33, 26 July 2022 (UTC)