Talk:Climate change feedbacks/Archive 1

Archive 1

Probation

Would somebody care to import some relevant talk page templates here from the parent article? In particular I recommend adding this page to the climate change probation. --Tasty monster 20:07, 14 February 2010 (UTC)

 Done. Do you want the "No forum", and other warnings as well? The article doesn't seem controversial, but it's your call. ChyranandChloe (talk) 03:46, 15 February 2010 (UTC)

Merge pages suggestion

Since Tipping point page and Runaway climate change page are conclusions based on the effects of climate change feedbacks, they should be merged into this page. What say you?

Id447 (talk) 20:05, 8 April 2010 (UTC)

Distinguish from Climate forcing

How is this distinguished from what would be in climate forcing if it weren't redirected to radiative forcing? I do see it. Hansen's quote, "Forcings determine the if the climate is warming or cooling. Feedbacks determine the how much and how fast the climate changes", which seems to be attempting to do so, is objectively false. — Arthur Rubin (talk) 22:28, 20 April 2010 (UTC)

I would propose a merge, but "climate forcing" has been redirected to radiative forcing, which is not entirely correct. There are other climate forcing mechanisms which are not radiative forcing. — Arthur Rubin (talk) 22:31, 20 April 2010 (UTC)

Probably the simplest distinction is that forcing tends to be external to the climate system (variations in solar intensity, plate tectonics, volcanic eruptions, changes to atmospheric composition, etc) while feedbacks are internal. The distinction is not hard and fast: for example changes in atmospheric composition can be either forcing or feedback depending on the time scale and other things. (BTW did you mean "do" (as written) or "don't" in your first post to the thread?) Short Brigade Harvester Boris (talk) 00:30, 21 April 2010 (UTC)

I meant "don't". That's a plausible distinction, but it's not in the article, and it's contradicted by Hansen, so we would need a good source. — Arthur Rubin (talk) 00:44, 21 April 2010 (UTC)

Most any textbook would do. Or how about this from the NAS? Short Brigade Harvester Boris (talk) 00:54, 21 April 2010 (UTC)

That's certainly an improvement over what we have in the article, but it distinguishes a "forcing" (meaning an individual parameter which can be altered) and "feedback processes". "Feedbacks" (an individual parameter which cannot be directly altered) are not really mentioned in the NAS reference.

If we had an article at climate forcing, we could properly discuss the differences, here or there, but WLU seems to believe that such as not necessary. — Arthur Rubin (talk) 03:03, 23 April 2010 (UTC)

I'm at a loss to figure out what point you're trying to make here. My guess is that you're somehow trying to make a distinction between "feedbacks" and "feedback processes"? Short Brigade Harvester Boris (talk) 03:09, 23 April 2010 (UTC)

The lede carefully avoids supplying a definition, and the most obvious one (due to Hansen's confusion) is indistinguishable from "forcing". I'm trying to find out what the article is supposed to be about, before suggesting a definition. If it is to be (climate) feedback processes, it would make sense, except quite a bit of the lede needs to be rewritten. But I don't know if that's the intent. — Arthur Rubin (talk) 08:48, 23 April 2010 (UTC)

Hansen's quote, "Forcings determine the if the climate is warming or cooling. Feedbacks determine the how much and how fast the climate changes", which seems to be attempting to do so, is objectively false. - not sure what you think is wrong with that. Could you explain William M. Connolley (talk) 09:13, 23 April 2010 (UTC)

Among other reasons, multiple feedback systems (we still don't have a definition of "feedbacks") can change the direction of the climate change caused by an single forcing, thereby making both sentences false. More precisely, a feedback system can make the long-term change in the opposite direction of the short-term change. (A single feedback cycle probably cannot change the direction, but I may not be sufficiently creative in allocating the differential equations. A single feedback system with multiple factors can change the direction from the direct effect of a single forcing. ) — Arthur Rubin (talk) 16:45, 23 April 2010 (UTC)

I think it would be helpful if you could give an example of what you mean William M. Connolley (talk) 18:19, 23 April 2010 (UTC)

Bit of a loss as to what the question is here. Inputs to a system like this are (assumed to be) independent of system dynamics. So I don't see how they can be the same. Guettarda (talk) 19:52, 23 April 2010 (UTC)

It is a bit of a stretch to make inputs (the creator of the category Category:Climate Feedbacks used the example of coal-fired power plants) the same as internal parameters, not directly human-controled; but even human-controlled systems are affected by the climate, so they are still (human-moderated) feedbacks.

But what I'm now asking is what is a "feedback" in this context; is it a feedback system, or a specific not-directly-human-controlled parameter. IPCC seems to use the former (feedback system), but the lede seems to be using the latter. In either case, there should be a definition in the lede, with Hansen's incorrect explanation moved into the text. —Preceding unsigned comment added by Arthur Rubin (talk • contribs)

Honestly, I can't make sense of the first sentence of your reply at all. As for the rest - it's little better. And can you explain why Hansen's explanation is wrong? It would help a lot if you would say what you're thinking, rather than ask questions. Guettarda (talk) 20:40, 23 April 2010 (UTC)

I can't think of any possible interpretation of the words "forcing" or "feedback" which makes Hansen's statements correct, but I can only think of a few possible interpretations in which it is meaningfull, so there may be something I'm missing. In any case, we need a definition of the term. — Arthur Rubin (talk) 06:14, 24 April 2010 (UTC)

If anyone is interested, here is the link to the definition of climate forcings per IPCC. Radiative_forcing#IPCC_usage. From the IPCC, Third Assessment Report, the definition of climate feedbacks can be found at Working Group I: The Scientific Basis and scroll down to

Climate feedback

An interaction mechanism between processes in the climate system is called a climate feedback, when the result of an initial process triggers changes in a second process that in turn influences the initial one. A positive feedback intensifies the original process, and a negative feedback reduces it.

If anyone knows why 'This article has been placed on article probation.' applies to this article, please let me know.

If anyone is interested in the source of statements by Hansen, I can be of help. What is required to convince doubters that Hansen's book contains the referenced statements?

Id447 (talk) 04:11, 25 April 2010 (UTC)

That's certainly an improvement over what was in the article 14 hours ago. Why don't you put the IPCC defintion in the lede, and move Hansen's (bizarre, in my opinion) commentary to an overview section. — Arthur Rubin (talk) 07:48, 25 April 2010 (UTC)

I've still got no idea what AR thinks is wrong. But there were some things that I thought we re wrong, so I've revised it a bit William M. Connolley (talk) 18:15, 25 April 2010 (UTC)

The lede is very confusing. I've added the external/internal bit (sourced from NAS) as something concrete that we might use to anchor the definition. Short Brigade Harvester Boris (talk) 20:17, 25 April 2010 (UTC)

It appears that AR is a highly intelligent individual however I’m not impressed with his understanding of the subject, climate feedback. Also it appears that AR highly values academic sources for Wikipedia entries.

Id447 (talk) 21:09, 27 April 2010 (UTC)

Banner Removal

I am unable to determine the use of the banner "This article needs additional citations for verification. Please help improve this article by adding reliable references. Unsourced material may be challenged and removed. (May 2008)". I am removing it. If this is an error please let me know what needs to be done.

--Id447 (talk) 05:01, 22 June 2010 (UTC)

Lapse rate?

The current (sole) ref for the lapse rate feedback isn't much use. IPCC says that "The close link between these processes means that water vapour and lapse rate feedbacks are commonly considered together. The strength of the combined feedback is found to be robust across GCMs, despite significant inter-model differences, for example, in the mean climatology of water vapour" [1] William M. Connolley (talk) 08:56, 22 June 2010 (UTC)

And again: I've removed The effect is reduced by lapse-rate feedback [2] for consideration. This looks to be a paraphrase of The spread among models in the water vapor feedback is, however, largely compensated by an opposite spread in the “lapse-rate feedback,” a negative feedback that occurs because a warmer atmosphere radiates more power to space, thereby reducing net surface warming. As a result, the sum of the two feedbacks is insensitive to errors in predicted warming of the upper troposphere, and at first sight it is wrong: that is saying that in climate models the two feedbacks are generally found to covary in such a way as to cancel errors (or differences). It isn't clear that The effect is reduced by lapse-rate feedback is correct (or even the closer The effect is compensated by lapse-rate feedback. Discuss William M. Connolley (talk) 17:39, 2 September 2010 (UTC)

The conclusion is roughly correct but the reasoning is messed up. I've got too much RL stuff to do right now to go into a lot of detail, but basically to the extent that the lapse rate is approximately moist adiabatic, a given increase in surface temperature produces a much larger increase in temperature aloft, thus reducing the lapse rate and increasing radiation lost to space. Short Brigade Harvester Boris (talk) 17:51, 2 September 2010 (UTC)

Atmoz edits cleaned up the problem

it may be the kiss of death, but I support his corrections. --Africangenesis (talk) 22:35, 21 October 2010 (UTC)

Wording needs tweaking

The statement in the ice-albedo feedback section :

The Antarctic sea ice reached its greatest extent on record since the beginning of observation in 1979,[56] but the gain in ice in the south is exceeded by the loss in the north. The trend for global sea ice, northern hemisphere and southern hemisphere combined is clearly a decline.[57]

could use some attention. While is may have been correct at the time it was added, to state that the net anomaly was negative, it is positive at the moment. Note that footnote 57 is a link to an updated graph, so current results can be seen. It appears to be the case that it has been negative more often than positive in this century, but given the current positive value, the sentence needs amending. It is also likely true that the trend line has a negative slope, but as there is no trendline, and the last few months show a value above the 1979–2008 mean, it is hardly "clear" that there is a decline. More nuanced wording, ideally supported by an actual calculation of a trendline supported by an RS would help.--SPhilbrick(Talk) 16:49, 3 June 2013 (UTC)

Oceans feedback

The oceans first and foremost provide a negative feedback by absorbing and sequestering carbon. While this ability may be attenuated with warmer oceans, it doesn't flip it into a 'positive feedback' I find it deceptive to list Oceans under POSITIVE. Toddie 18:39, 24 May 2015 (UTC) — Preceding unsigned comment added by Toddrav (talk • contribs)

Todd, you are required to WP:Assume good faith, or your contributions aren't really helpful or desired. Application of AGF would conclude simply that someone made a mistake. I agree that "Carbon uptake by oceans" does not belong under the "Positive" list; for that matter, the topic of ocean uptake is already described in the "negative feedbacks" section.

I have removed the text formerly under "positive" and am posting here. Maybe there is useful links, refs, etc that should be merged into the existing subsection under negative feedbacks - carbon cycle. The removed text was

==== CO₂ uptake by oceans ====

{{main|Airborne fraction}}

{{Further|Effects of global warming#Oceans}}

Cooler water can absorb more CO₂ than warmer water. As ocean temperatures rise the oceans will absorb less CO₂ resulting in more warming. Conversely when cooler the oceans have absorbed more CO₂, resulting in further cooling. There is about 50 times more carbon in the oceans than there is in the atmosphere.<ref>Netting, Ruth, [http://science.nasa.gov/earth-science/oceanography/ocean-earth-system/ocean-carbon-cycle/ "Carbon Cycle - NASA Science"], ''NASA'', Last Updated: April 5, 2010, Accessed 4/22/2010</ref>

In addition to the water itself, the ecosystems of the oceans also sequester carbon. Their ability to do so is also expected to decline as the oceans warm: Warming reduces the nutrient levels of the [[mesopelagic zone]] (about 200 to 1000 m deep), which limits the growth of [[diatom]]s in favor of smaller [[phytoplankton]] that are poorer [[biological pump]]s of carbon.<ref>{{Cite doi|10.1126/science.1137959}}</ref>

NewsAndEventsGuy (talk) 22:54, 25 May 2015 (UTC)

The thing is, the Ocean first acts as a negative feedback on increased CO2 levels, but at one point is projected to sequester less. This study on feedbacks describes processes related to feedbacks and ocean. The ocean is part of the carbon cycle, and this should be mentioned. I think rather than to remove the content, adjustments should be made.

Another example

For instance, higher temperatures may lead to increased release of CO2 , methane and N2O 3 from terrestrial ecosystems and to increased oceanic denitrification and stratification, resulting in nutrient limitation of algal growth reducing the CO2 sink to the ocean. Also, CaCO3 neutralization in the ocean is reduced at higher temperatures [Archer et al., 2004]. Several analyses with elaborate coupled climate-carbon models that take such feedbacks into account suggest an overall amplification of the effects of anthropogenic addition of greenhouse gases to the atmosphere [Cox et al., 2000; Friedlingstein et al., 2001; Prentice et al., 2001; Friedlingstein et al., in press]. However, we are still far from able to compute the relative strengths of the multitude of known (and unknown) relevant processes on a global scale with much precision [Prentice et al., 2001; Friedlingstein et al., 2003].

prokaryotes (talk) 23:00, 25 May 2015 (UTC)

Obviously, the article attempts to present a list - that is to say, a big picture list - of various component mechanisms. If we name some major component of the climate system, such as 'oceans', yeah.... we could wander off into a confusing house of mirrors trying to describe the entire system's interactions simultaneously. Better, in my view, to break down the individual pieces - such as carbon uptake - and list those under "positive" or "negative" based on current status. If further climate change is projected to increase/decrease their impact, fine... we can mention that in the text. NewsAndEventsGuy (talk) 23:04, 25 May 2015 (UTC)

Good, please add something about it. prokaryotes (talk) 23:07, 25 May 2015 (UTC)

If you had understood what I wrote, you would have known that there were already two subsections addressing oceanic carbon uptake. What, you want me to add a third? NewsAndEventsGuy (talk) 03:56, 26 May 2015 (UTC)

The ocean parts need to be extended still. See above quotes. If you do not add it into the article, fine. Someone else will do it then. prokaryotes (talk) 04:51, 26 May 2015 (UTC)

Oceans feedback

The oceans first and foremost provide a negative feedback by absorbing and sequestering carbon. While this ability may be attenuated with warmer oceans, it doesn't flip it into a 'positive feedback' I find it deceptive to list Oceans under POSITIVE. Toddie 18:39, 24 May 2015 (UTC) — Preceding unsigned comment added by Toddrav (talk • contribs)

Todd, you are required to WP:Assume good faith, or your contributions aren't really helpful or desired. Application of AGF would conclude simply that someone made a mistake. I agree that "Carbon uptake by oceans" does not belong under the "Positive" list; for that matter, the topic of ocean uptake is already described in the "negative feedbacks" section.

I have removed the text formerly under "positive" and am posting here. Maybe there is useful links, refs, etc that should be merged into the existing subsection under negative feedbacks - carbon cycle. The removed text was

==== CO₂ uptake by oceans ====

{{main|Airborne fraction}}

{{Further|Effects of global warming#Oceans}}

Cooler water can absorb more CO₂ than warmer water. As ocean temperatures rise the oceans will absorb less CO₂ resulting in more warming. Conversely when cooler the oceans have absorbed more CO₂, resulting in further cooling. There is about 50 times more carbon in the oceans than there is in the atmosphere.<ref>Netting, Ruth, [http://science.nasa.gov/earth-science/oceanography/ocean-earth-system/ocean-carbon-cycle/ "Carbon Cycle - NASA Science"], ''NASA'', Last Updated: April 5, 2010, Accessed 4/22/2010</ref>

In addition to the water itself, the ecosystems of the oceans also sequester carbon. Their ability to do so is also expected to decline as the oceans warm: Warming reduces the nutrient levels of the [[mesopelagic zone]] (about 200 to 1000 m deep), which limits the growth of [[diatom]]s in favor of smaller [[phytoplankton]] that are poorer [[biological pump]]s of carbon.<ref>{{Cite doi|10.1126/science.1137959}}</ref>

NewsAndEventsGuy (talk) 22:54, 25 May 2015 (UTC)

The thing is, the Ocean first acts as a negative feedback on increased CO2 levels, but at one point is projected to sequester less. This study on feedbacks describes processes related to feedbacks and ocean. The ocean is part of the carbon cycle, and this should be mentioned. I think rather than to remove the content, adjustments should be made.

Another example

For instance, higher temperatures may lead to increased release of CO2 , methane and N2O 3 from terrestrial ecosystems and to increased oceanic denitrification and stratification, resulting in nutrient limitation of algal growth reducing the CO2 sink to the ocean. Also, CaCO3 neutralization in the ocean is reduced at higher temperatures [Archer et al., 2004]. Several analyses with elaborate coupled climate-carbon models that take such feedbacks into account suggest an overall amplification of the effects of anthropogenic addition of greenhouse gases to the atmosphere [Cox et al., 2000; Friedlingstein et al., 2001; Prentice et al., 2001; Friedlingstein et al., in press]. However, we are still far from able to compute the relative strengths of the multitude of known (and unknown) relevant processes on a global scale with much precision [Prentice et al., 2001; Friedlingstein et al., 2003].

prokaryotes (talk) 23:00, 25 May 2015 (UTC)

Obviously, the article attempts to present a list - that is to say, a big picture list - of various component mechanisms. If we name some major component of the climate system, such as 'oceans', yeah.... we could wander off into a confusing house of mirrors trying to describe the entire system's interactions simultaneously. Better, in my view, to break down the individual pieces - such as carbon uptake - and list those under "positive" or "negative" based on current status. If further climate change is projected to increase/decrease their impact, fine... we can mention that in the text. NewsAndEventsGuy (talk) 23:04, 25 May 2015 (UTC)

Good, please add something about it. prokaryotes (talk) 23:07, 25 May 2015 (UTC)

If you had understood what I wrote, you would have known that there were already two subsections addressing oceanic carbon uptake. What, you want me to add a third? NewsAndEventsGuy (talk) 03:56, 26 May 2015 (UTC)

The ocean parts need to be extended still. See above quotes. If you do not add it into the article, fine. Someone else will do it then. prokaryotes (talk) 04:51, 26 May 2015 (UTC)

Cloud feedback

Why is cloud feedback only under the positive feedbacks? Just about any paper states that it can be both. That the IPCC states that it is "more likely a positive than a negative feedback" doesn't change that. SymbolicFrank (talk) 02:29, 22 July 2013 (UTC) The same reason every other climate change article is badly written at wikipedia..... — Preceding unsigned comment added by 24.207.135.183 (talk) 11:40, 8 September 2015 (UTC)

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Methane release from hydrates section needs update

Just to say this section is way out of date now. There has been a lot of research in the last couple of years especially, 2017-8 that casts doubt on the earlier picture.

Here is how the IPCC summarize the latest research in 2017:

"Clathrates: Some economic assessments continue to emphasise the potential damage from very strong and rapid methane hydrate release, although AR5 did not consider this likely. Recent measurements of methane fluxes from the Siberian Shelf Seas are much lower than those inferred previously. A range of other studies have suggested a much smaller influence of clathrate release on the Arctic atmosphere than had been suggested.

. A recent modelling study joined earlier papers in assigning a relatively limited role to dissociation of methane hydrates as a climate feedback. Methane concentrations are rising globally, raising interesting questions (see section on methane) about what the cause is, finally new measurements of the 14C content of methane across the warming out of the last glacial period show that the release of old carbon reservoirs (including methane hydrates) played only a small role in the methane concentration increase that occurred then."

A couple of us are working on this in Talk:Clathrate gun hypothesis - and have a fair number of issues with the article to work through - so for now this is just a note to editors of this page that your section here, while accurate when it was written, is based on papers that have not been backed up by the latest studies. Hopefully we can update this one once we have a consensus there.

But meanwhile it might be an idea to include the IPCC quote on this page, as it is more recent than any of the other cites used. What this page says about the PETM is also out of date - the methane hydrates idea is no longer a favoured hypothesis to explain the PETM either, because of data mismatches in ¹³C/¹²C carbon isotope ratios. There are other hypotheses that are a much better fit to the data including release of CO2 from deep coal deposits as a result of volcanism. More on this later -or if anyone else wnats to join in helping to update the Clathrate gun hypothesis article you are very welcome - do check out the talk page and particularly, Talk:Clathrate gun hypothesis#Some of the main points for attention Robert Walker (talk) 03:12, 13 August 2018 (UTC)

Bibliography

Hi there, I was thinking of expanding on some of the information in the article

Add information about chemical weathering feedback loop

Add information about Precipitation feedback Nramberg (talk) 21:48, 24 February 2019 (UTC)

Is Kump's paper a WP:PRIMARY or WP:SECONDARY source? We prefer secondary or even WP:TERTIARY ones. As for the 2nd source, I can't figure out what that is. Could you please add to the citation? Thanks for your interest in this article, we can use all the skilled and potentially skilled help we can get.NewsAndEventsGuy (talk) 22:35, 24 February 2019 (UTC)

References

Water vapor feedback

If water vapor feedback is positive, why is the humid adiabatic lapse rate (~3.5 to ~6.5 K / km) lower than the dry adiabatic lapse rate (~9.81 K / km)?

NASA says water vapor is a net atmospheric coolant: https://i.imgur.com/0DTVYkR.png

The Clough & Iacono study says water vapor is a net atmospheric coolant: https://web.archive.org/web/20190331141324if_/https:/co2islife.files.wordpress.com/2017/01/spectralcoolingrates_zps27867ef4.png

Thousands of other peer-reviewed studies show that water vapor isn't a positive feedback, it actually acts as a literal refrigerant (in the strict 'refrigeration cycle' sense) below the tropopause.

Methinks you've got your physics wrong. 71.135.47.108 (talk) 20:19, 4 July 2021 (UTC)

Methinks we don't do physics so we can't have it wrong. We're Wikipedia editors. If you like please post some draft text including what Wikipedia calls a "reliable source" to back it up because no one here is interested in your own WP:Original research NewsAndEventsGuy (talk) 00:16, 5 July 2021 (UTC)

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New figure for the lede?

Comprehensive diagram (originally from 2020)

More focused diagram (uploaded 26 July 2022+)

RCraig09 does great graphics work, but I wonder if the current lede graphic is the most appropriate image to have here. I think the nuances of this issue may be better captured by Figure TS.17 (p.96) in the WGI Technical Sumary report. I also think the current caption is somewhat misleading, based on that IPCC figure. I’d propose something myself, but I don’t have much experience with WP graphics. Dtetta (talk) 20:12, 24 July 2022 (UTC)

@Dtetta: I think Figure TS.17 is a bit too techy for a lead image. But I can also see how the existing "Comprehensive diagram" (at right) has a fair amount of detail that's not specifically related to feedback.

I propose that I make a simplified diagram that reduces the green "Effects on the environment" and the blue "Effects on humans" to smaller respective blocks, each with no content other than these two green and blue labels. I would also omit the three smaller boxes at the very top. In this manner, the content of the feedback sub-blocks will have greater prominence. Does that sound like a plan? I won't proceed without some consensus here, as it will take some tweaking work. —RCraig09 (talk) 23:05, 24 July 2022 (UTC)

@RCraig09: -thanks for considering this. In terms of complexity, I don’t know that Figure TS.17 is much different than the figure for the “Drivers of recent temperature rise” section in the main CC article, and the lead text in this article (particularly the last paragraph) is already pretty techy. But I get that a lead image would ideally be a little more accessible. I see a few options. One would be to do a figure similar to what you have here, but list some of the processes on TS.17 in a more plain English form. Another would be to just make a graphic focused on one examples each for positive and negative feedbacks, like is done on this Portland State University page, focusing on the positive and negative examples in the last paragraph of the lead. I guess another possibility would be to use the PSU image ideas, and then revise the last paragraph text to match those examples. I defer to you on what would be the best approach.Dtetta (talk) 00:04, 25 July 2022 (UTC)

Thanks. This will take some head-scratching. —RCraig09 (talk) 04:48, 25 July 2022 (UTC)

@Dtetta: I've made a new, more focused diagram. The different processes from Fig. TS.17 are similar to the processes in my diagrams. I felt it was important to show more than one process. If you see any substantive issues, let me know. —RCraig09 (talk) 05:15, 27 July 2022 (UTC)

I think it would be great to use the TS.17 Figure of the IPCC to define the major feedbacks. Our audience will not know that the Planck effect is not a feedback, so we should omit that one. There is a trade-off with understandability, as the carbon-land feedback is more easy to understand than the completely uncertain but possibly larger 'Other non−CO2 biogeochemical' feedback. It would be great if we can have the same three categories as the IPCC in the figure.

I also like the Portland State one, even if it looks a bit amateurish.

On the new block diagram figure, definitely an improvement, but the problem of low readability / small font size remains. I've not found any adequate software for these types of block diagrams, but consider using +/- rather than words. Cut out the "other effects", choose either global warming or climate change. Femke (talk) 16:27, 27 July 2022 (UTC)

@RCraig09: Since you asked me if I had substantive issues, I figured I’d respond to this latest version. I appreciate the effort you’ve made to revise the graph. But the new graph seems to only list the positive feedbacks that are described on TS.17. That figure clearly shows a number of negative feedbacks as well. So both the graphic and the caption are significantly biased towards giving the reader the impression that climate feedbacks are of the positive kind, and move the overall Earth system toward tipping points. That’s not really the case, from my reading of the TS. Although the radiative feedbacks overall are positive, when you add the Plank response, the net climate feedback parameter, as described on page 95, is negative. So the idea in the caption that feedbacks are moving us towards tipping points is just not correct, as far as I can tell, and it seems kind of alarmist.

I think the graphic would work much better if you just had a balanced presentation of both the positive and negative feedbacks, without getting into the overall net effect (since the exclusion of the Planck response seems like a bit of a technocratic sleight of hand). It would be nice if we could capture the major categories, as Femke has proposed, but it would also be helpful if you could just add the land and ocean responses to CO2 (since those seem relatively easy to mention in plain english terms), perhaps on the bottom right side of the graphic, as a way of balancing the positive feedback loops listed on the bottom left side. That would give the reader a more balanced perspective on the kinds of feedbacks that are significant, even if we don’t provide a complete coverage in the graphic.

And just to build on Femke’s opinion about the Portland graphic, I think it’s value is in having a circular depiction of that A to B back to A dynamic that is happening with most of these feedbacks. I think that’s a visually more powerful way of capturing feedbacks (as a loop). And I think if you just picked a couple of examples (one positive, one negative), maybe you could have a larger font size. Again, appreciate your willingness to consider all this. Dtetta (talk) 19:26, 27 July 2022 (UTC)

Thanks to all.

Preliminarily: I had included only positive feedbacks since the chart is about global warming, and I didn't think it was alarmist. I have removed reference to tipping points as I can see that might be perceived as alarmist even though the caption recited "toward tipping points".

I had paid attention only to the top panel in the Tech Report, since it was labeled "(a) Feedbacks in the climate system".

After reading your comments, and better appreciating the bottom panel of Figure TS.17, per your suggestion I'm thinking of adding boxes with "Land carbon response to CO2" and "Ocean carbon response to CO2" in blocks on the right side, in place of the green and blue blocks. That way, positive feedbacks would be labeled on the left side and negative feedbacks would be on the right side. I'd welcome expert suggestion as to exactly what specific wording to use.

The current diagram does show "loops", even if they're rectangular loops distinguished from the circular loops in the Portland reference. Adding curved arrows would take up space that would make fonts be smaller.

I'll await some more specific suggestions before I proceed with a next version. —RCraig09 (talk) 20:12, 27 July 2022 (UTC)

I have plunged ahead with the next version. However, I don't quite understand "Land carbon response to CO2" and "Ocean carbon response to CO2". Should arrows from those blocks point back to "Greenhouse gases" (reducing CO2) or to "Global Warming" (intrinsically cooling)? I think it's to "GHGs", but please verify before I upload. —RCraig09 (talk) 20:24, 28 July 2022 (UTC)

Faversham! I'm convinced the arrows should point to "GHGs", so I uploaded Version 3. Suggestions welcome; please be graphically specific. —RCraig09 (talk) 21:11, 28 July 2022 (UTC)

I think this is looking pretty good. For the negative feedback‘s I might say “CO2 uptake by plants and soils”, and then “CO2 uptake in oceans”. This would make those two elements a little more specific, like the positive feedbacks you list. On the top area, rather than plus and minus signs, I might say, for the left side, “Increased water vapor and methane (or CH4)”, and , on the right side, “Decreased CO2”. Guessing you can straddle the dotted line with those texts.

For the caption underneath the graphic, I suggest: “Some effects of global warming can either enhance (positive feedbacks) or inhibit (negative feedbacks) future warming.

Thanks for all your work on this! Dtetta (talk) 22:00, 28 July 2022 (UTC)

I've added simplified wording to the negative feedbacks, and increased color-coding of text (red=positive feedback and blue=negative feedback). I couldn't enhance the descriptions of text to left and right of "Greenhouse gases" because of a lack of physical space for fonts. —RCraig09 (talk) 05:35, 29 July 2022 (UTC)

Moved content about oceans

This paragraph was in the section on net primary production. It probably contains some nuggets of relevant info but in its current form I find it more confusing than anything, which is why I have cut it out:

++++++++

The climate change-exacerbated 2019–2020 Australian wildfires caused oceanic deposition of wildfire aerosols, enhancing marine productivity and thereby caused widespread phytoplankton blooms. While these increased oceanic carbon dioxide uptake, the amount likely pales in comparison to the ~715 million tons of CO₂ the fires emitted and can contribute to ocean acidification which, in turn, may induce toxic algal blooms but is thought to generally closely follow future atmospheric CO₂ concentrations as climate change feedbacks on ocean pH approximately cancel. EMsmile (talk) 10:35, 18 July 2023 (UTC)

References

EMsmile (talk) 10:35, 18 July 2023 (UTC)

Query about the image in the lead and the article overall

Some effects of climate change can either enhance (positive feedbacks) or inhibit (negative feedbacks) warming.

Noting the previous discussion from a year ago which User:Dtetta had started (see above), I'd like to come back to the image that is used in the lead (see on the right). My comments:

1. I am in particular concerned about the two boxes that are shown under "negative feedbacks"; I find them very unclear. Perhaps they could be clarified at least in the caption of the image. Is this really a "feedback" thing? Isn't it just an effect of CC that the additional CO2 in the atmosphere can enhance growth of plants and leads to ocean acidification? In which sense would this be much of a "negative feedback", i.e. having a significant impact on slowing climate change?
2. These terms of positive and negative feedbacks are actually confusing for the general public. For this reason, in the text of the article I have changed the section headings now to "Reinforcing feedbacks" and "balancing feedbacks". Could this be added into the chart as well? I know in science we talk about "positive feedback" but can we give our readers a little hint that positive is not a good thing here.
3. I think the graph is quite misleading because it gives the impression that the positives and negatives are almost in balance. This is far from the truth!
4. The image is also not very well synched with the words in the article. When you look at the text under "negative feedbacks" (now called "balancing feedbacks") it is actually very weak and says different things than what the image has there.
5. Personally, I think we are better off replacing that graph with a 2x2 image collage showing: permafrost melting, ice caps melting, increased water vapour and clouds, and then one showing an increase in net primary productivity in oceans (so 3 images for the positive feedback, one for the negative feedback).

Apart from this image, what do you all think of the status of this article? Where are its weaknesses? It doesn't have high pageviews (about 160 per day) so probably not worth sinking too much time into it. How well is it in synch with the article on tipping points in the climate system? From looking at it superficially, I don't see too much overlap with the tipping points article which is good but the two articles should refer to each other and be what I call "in sync". Pinging also User:InformationToKnowledge, User:Rhwentworth and User:ASRASR for their opinion. EMsmile (talk) 10:50, 18 July 2023 (UTC)

References

EMsmile (talk) 10:50, 18 July 2023 (UTC)

Yes, absorption of atmospheric carbon dioxide absorption is "a feedback thing", since reducing carbon dioxide in the atmosphere amounts to reducing a greenhouse gas that causes global warming. The scientific terms positive feedback and negative feedback are well understood and used extensively throughout reliable sources. Here, the caption recites "enhance" and "inhibit" specifically explain their meaning—specifically preventing any inference that positive feedbacks are a "good thing". Further, the caption's terms have wikilinks for science newbies to learn more. Replacing them with your own personal terms reinforcing feedbacks and balancing feedbacks actually avoids reliable source usage against fundamental Wikipedia policy. I will not be changing a diagram's accepted scientific terminology to comport with your personal terms. Conceptual block diagrams do not convey quantities, so, no, the diagram does not state, imply or suggest opposites are in balance. Much of this diagram is derived from and modeled after File:20200118 Global warming and climate change - vertical block diagram - causes effects feedback.svg which was the result of extensive group discussion at Talk:Climate change about three years ago. Lastly, pictures do not convey feedback mechanisms that are the subject of this article. —RCraig09 (talk) 17:36, 18 July 2023 (UTC)

I've just seen (in Google search results) that a few sources use reinforcing feedback and balancing feedback, but even general-public Google searches turn up massively more hits of positive feedback and negative feedback than the other terms. —RCraig09 (talk) 19:14, 18 July 2023 (UTC)

The Glossary of the 3949-page IPCC document that is used as a source at the end of the lead's first paragraph defines "Climate feedback An interaction in which a perturbation in one climate quantity causes a change in a second and the change in the second quantity ultimately leads to an additional change in the first. A negative feedback is one in which the initial perturbation is weakened by the changes it causes; a positive feedback is one in which the initial perturbation is enhanced." Your favored terms are apparently not used. —RCraig09 (talk) 19:28, 18 July 2023 (UTC)

I am not going to argue with you over this, as there is no point. I do think it's tech jargon to have a section heading called "Positive feedbacks". A good compromise could have been a section heading called "Positive feedbacks (enhancing climate change)" but I already know that I wouldn't be able to change your mind on this. So never mind.

In your reply you didn't address this point of mine "The image is also not very well synched with the words in the article. When you look at the text under "negative feedbacks" it is actually very weak and says different things than what the image has there." So either the image should be adjusted to include content of that section, or that section needs to be adjusted to include content that is summarised in the image. Currently, the section on negative feedbacks talks about these topics:

• Blackbody radiation (not shown in the image)
• Carbon cycle
  • Le Chatelier's principle (this is actually about oceans taking up CO2 which is in the image but I think the section sub-heading should be changed; and also it needs updating. It was written in 2010...)
  • Chemical weathering (not shown in the image)
• Net primary productivity (mentioned in the image but without using this term)
• Lapse rate (not shown in the image) - Pinging User:Sjsmith757 because they had added content there

Can someone who understands the negative feedbacks better than I do ensure that either the image is improved or the content in that section is improved, or both? EMsmile (talk) 08:56, 19 July 2023 (UTC)

Here, I must agree with RCraig09 that changing the terms which have been in use in tens of thousands of papers and other articles is not a good idea.

As for the rest, I would have to say that this article is unfortunately full of weaknesses. Many sections are so outdated that much of the article is essentially outright misleading. In regards to the image in particular, the main issue is that it appears to portray CO2 absorption by land and ocean as the main (or rather, the only) kind of negative feedback. In fact, while those sinks are certainly important, blackbody radiation is far more so. According to the leading expert on climate feedback loops and tipping points, Dr. Adam Armstrong McKay (the lead author of last year's Science assessment of tipping points):

Outgoing longwave radiation acts as the main major negative feedback, as hot things radiate more heat away. Positive feedbacks do not inevitably lead to runaway warming, as negative feedbacks will eventually counter them – if there were no negative feedbacks Earth would have become as hot as Venus long ago.

I was already planning to set aside time to update this article once I was able to update some of the more visible pages. Perhaps I should consider it a higher priority. InformationToKnowledge (talk) 15:43, 19 July 2023 (UTC)

— User:InformationToKnowledge, can you suggest particular concise wording I could add to the diagram that would capture the essence of the radiative counterbalance issue—but expressed in layman's terms? I'm initially thinking of "Earth's emanation to space of infrared (longwave) radiation", even though I'd prefer something less jargony if possible.

— EMsmile, the diagram's "Plants ... absorbing carbon dioxide" is part of the carbon cycle. Lapse rate is a quantification of temperature, related to radiation, as a function of altitude, and is not a separate phenomenon in this context. I've just asked InformationToKnowledge for a specific wording suggestion. . . . Separately, "positive feedback" and "negative feedback" are not jargony terms, as a Google search will attest; in a technical article, the scientifically dominant terms should be explained (as they are in the diagram caption and the lead) rather than being avoided or de-emphasized. As a matter of Wikipedia style, section names should be as concise as possible; their narrative text explains the section's subject.

— As I remember, the two negative feedback blocks included in the diagram were those suggested by User:Femke, who may have additional thoughts now. The two blocks were never presented as all-inclusive. With the addition of a radiative energy block, the diagram would better summarize the feedback concept—rather than "sync"ing to text that has been substantively criticized. —RCraig09 (talk) 16:40, 19 July 2023 (UTC)

Can we use the wording in the summary of this hot-off-the-presses (published a mere two days ago!) paper?

Earth's climate is stable because a warmer planet loses more energy to space, at infrared wavelengths invisible to the naked eye.

"Warmer planet loses more heat to space" sounds simple enough to fit on a graphic. (And the paper is CC-BY-4.0, so close paraphrasing shouldn't be a problem.) InformationToKnowledge (talk) 17:39, 19 July 2023 (UTC)

The JAMES article is a good find. However, in Talk:Greenhouse effect, there has been much debate as to how to characterize what gets radiated anywhere, and I'm disinclined to say "heat" (somewhat of a colloquial term) goes into space. I'm thinking that much of the public has seen the word infrared associated with warmth (as in infrared heat lamp), so I'm inclined to use it even though it is also "scientific". To link the concept to global warming itself, how about: "Warmed substances radiate more infrared energy into space"? (It will fit into a three-line block.) —RCraig09 (talk) 20:11, 19 July 2023 (UTC)

I am so happy to see InformationToKnowledge to join us here, thank you! As for the diagram I am really concerned that we are trying now to build up a new diagram more or less from scratch, rather than just using one that has already been published. Surely if we look hard enough we'll find a published diagram (under a compatible licence) and don't have to make one up ourselves? Wouldn't it be WP:OR if we developed our own diagram rather than staying at least very very close to one that has already been published? Or, if there is no such image available and nothing in the IPCC reports then perhaps the reason is that it's not so easy to show these complexities in a simple schematic?

I still think we could probably make 4 pictures to work (for the lead) if we had a suitable caption for a 2x2 image collage. Especially the permafrost thawing picture would be very easy to explain as a positive feedback effect. - Or otherwise perhaps it's "safer" to simply have no image in the lead at all.

(and by the way, a term can still be a jargon type term in the Wikipedia logic even if it gets a high amount of Google hits; perhaps lots of people are looking it up as they are confused about what "positive feedback" means. Or it could also be the kind of feedback that people get by their HR department about their performance at work etc. We don't have to avoid the term "positive feedback" altogether but I still think it could be helpful to explain it better in the section headings (yes, I know they are meant to be short). Even "enhancing" is not great as it's normally used for something that makes something better. Well perhaps some light copy editing could be done at the end where we ensure that people understand, and can read in more than one place in the article, that a positive feedback loop is one that makes the world more doomed, not better! (it might be abundantly logical for us but may not be so logical for people who are new to this topic) EMsmile (talk) 21:06, 19 July 2023 (UTC)

@EMsmile I will offer my opinion, but I just want to preface that my expertise is in climate science but not in the usage/policies of Wikipedia and so I can't speak to some of the points brought up here.

On the subject of the language positive/negative feedback:

I think I agree with most of what has been said here. These are standard terms in science, but they are definitely not easily understood by a lay audience. To a lay audience, "positive feedback" is when your employer tells you "good job". So I think I would lean towards categorizing it as jargon. However, there are times (and I believe this is one) where it is appropriate to teach the jargon. The purpose of the article is to explain climate feedbacks. I think I would suggest referring to positive feedbacks as destabilizing and negative feedbacks as stabilizing. I think that might capture the connotation and meaning a bit better. As pointed out in one of the quotes, we expect the stabilizing to win out eventually, unless we cross a tipping point. I would support section headings titled Positive (destabilizing) Feedbacks and Negative (stabilizing) Feedbacks, or something to that effect.

Regarding negative feedbacks:

@InformationToKnowledge is correct that the Planck feedback is the dominant negative feedback. Something along the lines of what has been suggested by @RCraig09 seems reasonable. Perhaps "a warmer Earth emits/loses more (infrared) energy to space".

However, one current issue with the article from a scientific perspective is that it confuses carbon cycle feedbacks and climate change feedbacks. Specifically, climate feedbacks refer to processes that directly modify the amount of energy absorbed or released by the Earth, whereas carbon cycle feedbacks modify the amount of carbon dioxide in the atmosphere. In general, changes in the amount of carbon dioxide in the air are not considered climate feedbacks - the amount of CO2 is the input that is changed, and the feedbacks respond. This means that changes in CO2 held by land and ocean are not strictly climate feedbacks. This may sound a bit picky but it is important to consider the systems separately as they are distinct despite interacting. The IPCC does separate feedbacks from the carbon cycle (see this Figure from AR6 which might be useful for this page: https://www.ipcc.ch/report/ar6/wg1/figures/chapter-7/figure-7-10). But the entire page seems to combine them, and I think it might be worth considering separating the pages. Also because of this, the intro figure to this page is not really accurate. And I am not convinced editing it is the way to go, I think it should be possible to turn up an IPCC figure that would work. I'm happy to assist with that.

The lapse rate feedback is a tricky feedback overall because it is generally negative, except in polar regions where it is positive and it strongly contributed to polar amplified warming, one of the biggest consequences of climate change. I think @InformationToKnowledge is correct that the page could use some overall updates.

I hope those thoughts are of some help!

Sjsmith757 (talk) 03:04, 20 July 2023 (UTC)

Panel 3 of this figure could also be considered https://www.ipcc.ch/report/ar6/wg1/figures/technical-summary/figure-ts-14/. we'd need to make sure use is okay under the IPCC's copyright policy.

Sjsmith757 (talk) 03:15, 20 July 2023 (UTC)

A final figure

https://www.ipcc.ch/report/ar6/wg1/figures/technical-summary/figure-ts-17/

Sjsmith757 (talk) 03:17, 20 July 2023 (UTC)

You User:Sjsmith757 have brought up interesting points. I'm planning on updating the existing graphic, replacing "Plants and soil absorb carbon dioxide" with "Plants and soil remove carbon dioxide from air", so its connection to climate change is clear. Same change re "Oceans...". Within a day or two I'll add something to the graphic along lines of your suggestion, probably "Warmed Earth emits more infrared energy to space". That revised graphic will give us an updated discussion point. Separately, there have been extensive discussions over the years at Talk:Climate change about graphics, including font size readability; the IPCC diagrams are probably too complex to be readable in thumbnail view.

User:EMsmile, obviously I was referring to Google hits of positive/negative feedback in a scientific context. Here, the lead image caption and the lead's opening paragraph definitively distinguish these terms from an HR performance review and dispel any inference that "positive feedback" is a good thing. We should teach the dominant terms, not dilute them or "dumb them down". Separately, again, pictures simply do not convey the feedback mechanism without extensive captioning—which completely subverts the purpose of having a graphic! —RCraig09 (talk) 04:40, 20 July 2023 (UTC)