Comments
Redqueenhypo t1_j3lpfx9 wrote
You are at the same latitude as Ontario I believe. It is -2C there now, but 8C in London. You don’t want the Gulf Stream to halt.
mysteriouskiwi t1_j3mfcqh wrote
Yep, we're really quite high up, but our climate wouldn't really show that. Its very mild. No need for snow tyres or anything as we just don't get that cold regularly enough. Would be a rude awakening to us Brits if our winters went back to what our geological climate would be. Its always suprising when I haven't looked at a map for a while and remind myself that we are up in northern Canada. Just feels wrong haha
microwaffles t1_j3ncbdz wrote
North American land mass has the unfortunate problem of extending well into the Arctic Circle, so a cold air mass comes down unimpeded if the jet stream will allow it. I don't think British Isles or Europe could ever be as cold as Canada / Northern US
grumble11 t1_j3mtgag wrote
It is more complicated because the UK is a flat island next to the ocean, with winds blowing from west to east. Oceans moderate temperature even up north. It’ll be colder overall but not as cold as Toronto, which has a continental climate with a lot of mountains and land between the city and the ocean. Maybe Vancouver minus a couple degrees in London?
kavien t1_j3kvi0a wrote
So, a return to the Middle Ages? Wasn’t there a mini Ice Age during that time?
Guugglehupf t1_j3kvobt wrote
The Middle Ages where a really long time. There have been cold and warm phases. No real ice age, though.
Last cold spell that lasted a while was in the middle to late 1800s.
kavien t1_j3l2bi8 wrote
Thanks! I am too lazy to Google sometimes.
ExtensionNoise9000 t1_j3lahg4 wrote
Last ice age was about 10k years ago if I am not mistaken.
And the last Ice Age animation came out about 7 years ago.
UniversalMomentum t1_j3lqq3v wrote
We are currently in a ice age I believe it's less than about 2.5 million years.
The easiest definition for an ice age is just whenever there's ice at the poles year round.
We are at the warm cycle of an ice age but also in a hundred thousand year warming and cooling cycle which you can look up as the 100,000-year cycle or the interglacial cycle.
TSmotherfuckinA t1_j3lueq0 wrote
But what Ice Age sequel are we on?
-nocturnist- t1_j3li11e wrote
The person above was referring to this
kavien t1_j3m1ncc wrote
Yeah! That’s the one.
UniversalMomentum t1_j3lqgzm wrote
More like worse than anything in recorded human history, but also with 2 to 3 times the greenhouse gas levels to spice things up.
CornucopiaOfDystopia t1_j3lxg7y wrote
Yes, you’re probably thinking of the Little Ice Age, which inundated Europe starting during the Renaissance period:
https://en.wikipedia.org/wiki/Little_Ice_Age
It was theorized to have been caused by a similar reduction in Atlantic currents, though perhaps not nearly as complete as we may be facing ahead. So get some good blankets, Euros.
philomathie t1_j3l4tig wrote
Probably you are thinking of the maunder minimum, where the sun output less energy. The collapse of the gulf stream would probably be much worse.
[deleted] t1_j3kz0q2 wrote
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BurnerAcc2020 t1_j3lhj4v wrote
The article says that according to their findings, the Atlantic current does not collapse even by 2300 and even under the worst-case warming (only the Southern one does by that date) but sure, go ahead.
For the record, there was a paperabout the consequences of AMOC collapse in the UK, and they found roughly 3.4 degree cooling. The collapse in rainfall was far more important. EDIT: That paper, which is the one quoted below, was published three years ago and by a completely different group of researchers. Another user thinks the excerpt below is from the study in the article for some reason.
https://www.nature.com/articles/s43016-019-0011-3
> To address these issues, we consider a well-studied tipping point; collapse of the Atlantic Meridional Overturning Circulation (AMOC). The AMOC includes surface ocean currents that transport heat from the tropics to the northeast Atlantic region, benefiting Western Europe, including the agricultural system of Great Britain. We contrast the impacts of conventional (hereafter, ‘smooth’) climate change with those of a climate tipping point involving AMOC collapse on agricultural land use and its economic value in Great Britain, with or without a technological response. > > Our climate projections span 2020–2080 and use a mid-range climate change scenario as a baseline (Fig. 1a–f; also see Methods, subsequent discussion of uncertainties such as weather variability, and sensitivity analysis in Extended Data Fig. 10; the results reported in the main text are mean effects). We take an existing simulation of the effects of AMOC collapse and treat it as a set of anomalies that can be linearly combined with the baseline (smooth) climate change scenario. We nominally assume that AMOC collapse occurs over the time period 2030–2050 (Fig. 1g–l; see Methods). This is a low-probability, fast and early collapse of the AMOC compared with current expectations, emphasising the idealized nature of our study and our focus on assessing impacts. That said, the AMOC has recently weakened by ~15% and models may be biased to favour a stable AMOC relative to observations. > > ...Our remaining scenarios impose a collapse of the AMOC over the period 2030–2050 overlaid on the smooth climate change trend. A previous study that combined a rapid AMOC collapse with future climate projections showed that temperatures will continue to rise globally, but with a delay of 15 years, while British temperatures will be dependent on the AMOC. In the present study, the AMOC collapse reverses the warming seen in the smooth climate change scenarios, generating an average fall in temperature of 3.4 °C by 2080, accompanied by a substantial reduction in rainfall (−123 mm during the growing season. > > Holding real prices constant, in the absence of a technological response (that is, irrigation), rainfall (and to a lesser extent temperature) limitation due to AMOC collapse is predicted to affect arable farming in many areas (Fig. 2f,g). The expected overall area of arable production is predicted to fall dramatically from 32 to 7% of land area (Extended Data Figs. 2 and 3). This in turn generates a major reduction in the value of agricultural output, with a decrease of £346 million per annum (Table 1), representing a reduction in total income from British farming of ~10%. The key driver of the arable loss seen across Great Britain is climate drying due to AMOC collapse, rather than cooling (Fig. 3b,c). This adds considerably to the part of eastern England that is already vulnerable to arable loss due to drying under baseline climate change (green band in Figs. 2b and 3b). Part of eastern Scotland has a potential gain in arable production suppressed by the cooling effects of an AMOC collapse (contrast Figs. 2f and 3c), but the loss of potential arable production due to cooling is small compared with the impacts of drying. However, the assumption of constant real prices is less plausible under the major global food system dislocation caused by a collapse of the AMOC. While firm estimates are not available, substantial food price increases are thought to be likely. With the physical limits imposed by AMOC collapse constraining farm production, such price increases mean that wellbeing losses may be significantly higher than those calculated here, implying that our results should be viewed as lower-bound, conservative estimates of the impacts of such a scenario. > > With a change in technology to implement sufficient irrigation from 2050, the drying effects of the AMOC collapse on arable production could be substantially offset (Fig. 2h,i). In this scenario, land area under arable production still increases from 32 to 38% by 2080, with an accompanying increase in output value of £79 million per annum (Table 1 and Extended Data Fig. 3). Nevertheless, these increases in extent and value are lower than under the second scenario where the AMOC is maintained, due to lower temperatures (contrast Fig. 2b with Fig. 2h). Furthermore, the more extreme reduction in rainfall caused by the AMOC collapse means that water required for adequate irrigation is much greater than under the scenario where the AMOC is maintained. Under the AMOC collapse scenario, 54% of British grid cells now require irrigation, with demand exceeding 150 mm in the growing season for some areas in the south and east of England (and an average demand across irrigated areas of 70 mm of extra rainfall) (Fig. 4). This would require water storage (across seasons) or spatial redistribution across the country from areas of higher rainfall in the north and western uplands of Great Britain. Irrigation costs incurred in this scenario are estimated at over £800 million per year—more than ten times the value of the arable production it would support (see Methods). So, again, irrigation costs outweigh amelioration benefits under climate change—a difference that is massively inflated by the climate tipping point of AMOC collapse. Our analysis also indicates the level of food cost increase (nearly three-quarters of a billion pounds) necessary to justify such irrigation expenditure costs.
CornucopiaOfDystopia t1_j3ly0sn wrote
Literally not even your own quoted excerpt states that, so why are you posting this? What do you think is meant by your own quoted portion which states,
>In the present study, the AMOC collapse reverses the warming seen in the smooth climate change scenarios, generating an average fall in temperature of 3.4 °C by 2080, accompanied by a substantial reduction in rainfall (−123 mm during the growing season.
Why are you deliberately and confidently misrepresenting the science on this, in multiple parts of this thread?
IAreATomKs t1_j3m2m7z wrote
Am I crazy? He seems to be staying exactly what's in the quote.
[deleted] t1_j3m9ko6 wrote
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AftyOfTheUK t1_j3m5btg wrote
He isn't, at least not in this post.
Perhaps you could quote the thing you think he has said which is misleading? Might help to explain our different understandings of what he said.
mrbucknut t1_j3me8zp wrote
BurnerAcc2020 didn't misrepresent anything, you just failed at reading comprehension. They correctly state the stated affects by 2300 from the posted article. They then reference another source with a different prediction, and what the worst case scenario is per that quoted article. 2 different articles with different prediction/conclusions, a presented that way. The quoted article is around 2 years older so that is another thing to consider when evaluating both.
CornucopiaOfDystopia t1_j3mfjkn wrote
But they did it specifically to downplay concerns that they purposefully misrepresented to be about total collapse, when even the parent comment merely and correctly expressed concerns about the current being altered, perhaps as it was when Europe was plunged into the Little Ice Age a few hundred years ago causing terrible famines and extreme cold. To attempt to reframe those concerns as being only about 100% shutdown of the current is an egregious and fallacious strawman of the argument.
But even aside from that, as I said, their own references do not support their implication that the concerns are not appropriate for generations. Just because a study is three years old doesn’t mean that the cause for concern it might raise can be dismissed. There is a clear scientific consensus that thermohaline cycle disruption is a real threat to humanity, with potential for catastrophe well before 2300, and yet reading only the comment I critiqued, one would never know that. That is extremely problematic in a discussion like this one, and I stand by my critique.
Wouldwoodchuck t1_j3m7of9 wrote
*will be like Canada or Russia…. Insert dog with room on fire meme…
[deleted] t1_j3li5w0 wrote
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GodToldMeToPostThis t1_j3ipb0g wrote
The difference in salinity and temperature in deep ocean currents is extremely slim under normal conditions.
[deleted] t1_j3jzlvw wrote
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[deleted] t1_j3kizmm wrote
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HipsterCavemanDJ t1_j3l0768 wrote
Or, you know, oxygen.
Kalapuya t1_j3mfpnw wrote
This is misleading. We do not “depend” on the ocean for oxygen as the atmospheric reservoir has more than sufficiently built up over the last 2 billion years. About half of the slow drop that built it up came from the oceans, but even if it ceased doing so tomorrow we wouldn’t be deprived of O2 for a long time.
[deleted] t1_j3lhw9a wrote
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BurnerAcc2020 t1_j3lirk6 wrote
Is 2300 your definition of "swiftly"? That's when their paper actually finds that the current collapses - and not even the Atlantic one but the one in the Southern Ocean, and only under very high warming. It's actually slower than some earlier papers which did project AMOC collapse - in 2200s or so, and again only under very high warming.
As for food security, there was an interesting paper on that earlier.
https://www.nature.com/articles/s41467-020-15708-9
>Significant biomass changes are projected in 40%–57% of the global ocean, with 68%–84% of these areas exhibiting declining trends under low and high emission scenarios, respectively.
>
>...Climate change scenarios had a large effect on projected biomass trends. Under a worst-case scenario (RCP8.5, Fig. 2b), 84% of statistically significant trends (p < 0.05) projected a decline in animal biomass over the 21st century, with a global median change of −22%. Rapid biomass declines were projected across most ocean areas (60°S to 60°N) but were particularly pronounced in the North Atlantic Ocean. Under a strong mitigation scenario (RCP2.6, Fig. 2c), 68% of significant trends exhibited declining biomass, with a global median change of −4.8%. Despite the overall prevalence of negative trends, some large biomass increases (>75%) were projected, particularly in the high Arctic Oceans.
>
>Our analysis suggests that statistically significant biomass changes between 2006 and 2100 will occur in 40% (RCP2.6) or 57% (RCPc8.5) of the global ocean, respectively (Fig. 2b, c). For the remaining cells, the signal of biomass change was not separable from the background variability.
>
> ...Furthermore, under RCP8.5, consistent relationships were also observed between projected animal biomass changes and SES indicators (Fig. 3c, d), with more severe declines projected in regions with low SES. For example, Fig. 3c shows geographic patterns of projected biomass change and the human development index (HDI) within each EEZ (Fig. 3c, map), as well as the emergent relationship between them (Fig. 3c, right panel). The significant positive relationship between the HDI (Fig. 3c) and the mean rate of projected biomass change under RCP8.5 (p < 0.0001; r2 = 0.16) indicates that higher climate-driven biomass losses are projected to disproportionally occur within the EEZs of the least developed states. In addition to development status, states experiencing the greatest pressures such as high levels of undernourishment, food debt and insecurity, fishery dependency, and economic vulnerability to climate change are projected to experience the greatest losses of marine animal biomass over the coming century. These states also have the lowest ocean health scores, lowest wealth and adaptive capacity, and contribute the least to global CO2 emissions on a per capita (r2 = 0.13; p < 0.0001) and national basis (r2 = 0.1; p < 0.0001). The relationships between projected biomass and almost all SES indicators became weaker and often non-significant under a strong greenhouse gas mitigation scenario (RCP2.6; Fig. 3d).
>
> Under RCP8.5, states that currently have a higher proportion of undernourishment are projected to experience the largest climate-driven reductions in animal biomass. This relationship is troubling, given that seafood accounts for 14–17% of the global animal protein consumed by humans, but with much higher reliance in small island states, where it is vital to maintaining good nutrition and health43. Declining animal biomass within the EEZs of states that are already experiencing poor nutrition may further exacerbate these deficiencies, particularly as these states also tend to be more dependent on fisheries, have low food security and high food debts (Fig. 3d). Changes in nutrition related to declining fisheries productivity could potentially be offset by increased agricultural production, aquaculture, or modifying food distribution systems12. Yet, recent studies have also highlighted the importance of seafood as a critical source of essential micronutrients that are currently lacking in the diets of up to 2 billion people. These micronutrient deficiencies and their consequences are particularly severe in Asian and African countries, many of which are projected to experience severe reductions in marine animal biomass under RCP8.5 (Fig. 2b).
>
> To explicitly evaluate the effect of strong emission mitigation on future animal biomass, we calculated the difference in projected biomass with the strongest mitigation scenario (RCP2.6) relative to those under a worst-case scenario (RCP8.5) within each EEZ and by continent (Fig. 4). The relationship between projected biomass under RCPs 8.5 and 2.6 was positive (r = 0.53) but also suggested that the effects of strong mitigation on biomass were not purely additive: some states experienced disproportionate biomass gains (Fig. 4a, above diagonal line) or losses (Fig. 4a, below diagonal line) from strong, relative to weak mitigation. Although mitigation led to increased biomass relative to worst-case emissions within the EEZs of almost all states, it resulted in declines within the EEZs of Morocco (−1%), Chile (−10%), Spain (−12%), and Russia (−12%; Fig. 4a). Relative to a worst-case scenario, the largest biomass gains from mitigation were observed for African, Asian, and South American states, including Yemen (50%), Oman (49%), Cambodia (48%), Guinea Bissau (46%), Suriname (45%), and Pakistan (44%).
For the record, the two scenarios in that paper are "between 1.5 and 2 degrees" and "between 4 and 5 degrees" by the end of the century, and we are currently tracking for almost exactly in between the two, with a potential to get closer or even meet that former scenario.
CornucopiaOfDystopia t1_j3lyhuj wrote
Their paper absolutely does not claim that, and your own excerpt from it shared elsewhere in this thread states it clearly:
>In the present study, the AMOC collapse reverses the warming seen in the smooth climate change scenarios, generating an average fall in temperature of 3.4 °C by 2080, accompanied by a substantial reduction in rainfall (−123 mm during the growing season.
2080 is quite a lot sooner than “2300.”
Why are you deliberately and confidently misrepresenting the science on this, in multiple parts of this thread?
BurnerAcc2020 t1_j3m4s77 wrote
That excerpt is from a study which is nearly three years old, genius. It has almost nothing to do with the study in the article, and it does not predict that there would be a collapse at that point, either, because it does not actually examine the current at all. What it does is examine the weather in the UK under the assumption it did collapse at that point. I even included the part where they say exactly that in the excerpt.
> This is a low-probability, fast and early collapse of the AMOC compared with current expectations, emphasising the idealized nature of our study and our focus on assessing impacts.
Still, next time actually click on the links. You'll learn a lot more that way.
CornucopiaOfDystopia t1_j3m70z7 wrote
And yet you used it to imply that there was no reason for any concern whatsoever, even though conditions well before a complete collapse would still be disastrous and catastrophic. That is misleading at worst, and bad science at best.
Your attitude and tone in lines like this one,
>That excerpt is from a study which is nearly three years old, genius
Is not appropriate here. If your goal is to actually engage people in an educational and scientific manner, you are failing quite badly.
BurnerAcc2020 t1_j3mey0t wrote
My cornucopian, you have repeatedly made accusations against me in this thread which were entirely based on your inability to understand what I wrote and do even the most cursory research like the clicking the OOP article or my links. If you want to see better attitude from me, how about you delete all of those comments, or edit them to acknowledge what you got wrong?
> even though conditions well before a complete collapse would still be disastrous and catastrophic.
Depends on how you define these words, I guess. A rule of thumb, though: they wouldn't have led with an impact which occurs in 2300 in their headline if they were able to prove something truly dramatic in our lifetimes.
For the record, there actually was one relatively recent peer-reviewed paper which estimated that as long as the AMOC does not shut down entirely, its slowdown would be one of the few tipping points with a positive economic impact because it would help to cancel out the impacts of climate change, although those findings are far from universally accepted.
https://www.pnas.org/doi/full/10.1073/pnas.2103081118
> Slowdown of the AMOC reduces the expected SCC by 1.4% by reducing damaging warming in some countries.
> All AMOC slowdown scenarios result in a decrease in the expected SCC ranging from −0.7 to −5.7%, the latter in a scenario with a notably large two-thirds slowdown in the circulation.
(SCC stands for social cost of carbon and it's a bad thing, so it becoming lower is good.)
Kalapuya t1_j3mfx7x wrote
>nearly three years old
Things don’t change that quickly. That data is still perfectly relevant.
BurnerAcc2020 t1_j3mha38 wrote
Yes, which is why I brought it up in the first place. My point was that merely looking at the publication date would have shown that the link with the exceprt is too old to have anything to do with the OOP post outside of studying similar subject matter, yet the other commenter did not even do that and thought the excerpt was from the present study.
corgibutt19 t1_j3ma1bx wrote
2300 is not very far away, especially on the historical timeline or when you consider how hard it will be to decrease the human contributions to warming. If we only care about the warming that will affect the living population, we are stupid and shortsighted.
BurnerAcc2020 t1_j3mfuss wrote
If what that paper means by "worst-case" is the same as the standard definition in this literature (hard to tell because of the paywall), then it essentially assumes continual acceleration of human contributions to warming, which is extremely implausible. (There are even some papers which argue that there are not enough fossil fuels to enable those rates of warming in the first place.) The rate of warming which is actually projected nowadays (see the last link in that comment) is well below that which is considered in the paper, and was found by the other papers I linked to have limited effects on at least the Atlantic circulation.
Earthling1a t1_j3iqrpv wrote
This has already begun.
BurnerAcc2020 t1_j3lk3pb wrote
Has it?
https://www.nature.com/articles/s41558-022-01342-4
> Observed SSTs and a large ensemble of historical simulations with state-of-the-art climate models suggest the prevalence of internal AMOC variability since the beginning of the twentieth century. Observations and individual model runs show comparable SST variability in the NAWH region. However, the models’ ensemble-mean signal is much smaller, indicative of the prevalence of internal variability. Further, most of the SST cooling in the subpolar NA, which has been attributed to anthropogenic AMOC slowing, occurred during 1930–1970, when the radiative forcing did not exhibit a major upward trend. We conclude that the anthropogenic signal in the AMOC cannot be reliably estimated from observed SST. A linear and direct relationship between radiative forcing and AMOC may not exist. Further, the relevant physical processes could be shared across EOF modes, or a mode could represent more than one process. > > A relatively stable AMOC and associated northward heat transport during the past decades is also supported by ocean syntheses combining ocean general circulation models and data, hindcasts with ocean general circulation models forced by observed atmospheric boundary conditions and instrumental measurements of key AMOC components. Neither of these datasets suggest major AMOC slowing since 1980, and neither of the AMOC indices from Rahmstorf et al. or Caesar et al. show an overall AMOC decline since 1980.
The paper itself does not even find that the Atlantic meriditional overturning circulation collapses on the timescales they investigated (between now and 2300) - only the one in the Southern Ocean, by 2300, and with continually increasing emissions. Granted, earlier, some other papers which did project the collapse of the Atlantic meriditional overturning circulation - in 2200s or so, and again only under very high warming.
CornucopiaOfDystopia t1_j3lyndo wrote
Literally not even what your own quoted excerpt from elsewhere in this thread states that, so why are you posting this? What do you think is meant by your own quoted portion which states,
>In the present study, the AMOC collapse reverses the warming seen in the smooth climate change scenarios, generating an average fall in temperature of 3.4 °C by 2080, accompanied by a substantial reduction in rainfall (−123 mm during the growing season.
Why are you deliberately and confidently misrepresenting the science on this, in multiple parts of this thread?
silas67r t1_j3jshf2 wrote
Why is disaster in quotations?
mycatisgrumpy t1_j3jw17q wrote
Because "disaster" is light-hearted sarcasm. What they actually mean is "completely fucked."
SillyFlyGuy t1_j3kwoby wrote
You seem "upbeat" about this.
Content_Date_318 t1_j3mtc1o wrote
Yeah I don't understand why people feel the need to be so negative about this! We're only looking at something that will probably be worse than the Permian extinction event. no big deal really.
Gemini884 t1_j3noquw wrote
> worse than the Permian extinction event.
​
Read IPCC report on impacts and read what climate scientists say instead of speculating-
https://nitter.kavin.rocks/MichaelEMann/status/1432786640943173632#m
https://nitter.42l.fr/ClimateAdam/status/1553757380827140097
https://nitter.42l.fr/GlobalEcoGuy/status/1477784375060279299#m
https://nitter.42l.fr/JacquelynGill/status/1553503548331249664#m
https://nitter.kavin.rocks/hausfath/status/1533875297220587520#m
https://nitter.42l.fr/JacquelynGill/status/1513918579657232388#m
https://nitter.42l.fr/waiterich/status/1477716206907965440#m
Information on marine biomass decline from recent ipcc report: "Global models also project a loss in marine biomass (the total weight of all animal and plant life in the ocean) of around -6% (±4%) under SSP1-2.6 by 2080-99, relative to 1995-2014. Under SSP5-8.5, this rises to a -16% (±9%) decline. In both cases, there is “significant regional variation” in both the magnitude of the change and the associated uncertainties, the report says." phytoplankton in particular is projected to decline by ~10% in worst-case emissions scenario.
https://www.nature.com/articles/s41558-021-01173-9/figures/3
It is likely that the proportion of all species at very high risk of extinction (categorised as “critically endangered” by the IUCN Red List) will reach 9% (maximum 14%) at 1.5C, 10% (18%) at 2C, 12% (29%) at 3C, 13% (39%) at 4C and 15% (48%) at 5C, the report says.
Content_Date_318 t1_j3npfo8 wrote
I'm sorry but, many of these models have been shown to be incredibly conservative and leave out many variables which is why "sooner than expected" is a catch phrase among climate scientists.
I read reports religiously.
Gemini884 t1_j3nrzhb wrote
Then why are climate models used in previous IPCC reports so accurate and have predicted the pace of warming so well?
https://www.realclimate.org/index.php/archives/2022/02/another-dot-on-the-graphs-part-ii/
You probably should listen to what climate scientists say on the matter-
https://nitter.kavin.rocks/hausfath/status/1557421984484495362
https://nitter.kavin.rocks/hausfath/status/1491134605390352388
https://nitter.kavin.rocks/JoeriRogelj/status/1424743837277294603
https://nitter.kavin.rocks/PFriedling/status/1557705737446592512
https://nitter.kavin.rocks/ClimateAdam/status/1429730044776157185
https://nitter.kavin.rocks/Knutti\_ETH/status/1554473710404485120
https://nitter.kavin.rocks/ClimateOfGavin/status/1556735212083712002#m
There were some models for the recent ipcc report that overestimate future warming and they were included too
https://www.nature.com/articles/d41586-022-01192-2
​
What about all the times it's been slower than expected and wasn't reported in media outlets?
Content_Date_318 t1_j3nytza wrote
Climate scientists will tell you that their long term models are getting BETTER but not 100% accurate because earth is an extremely complex system with many unknown variables and uncertainties. They don't account for permafrost thaw or dynamic vegetation feedback which contains vast amounts of methane for example.
https://www.carbonbrief.org/analysis-how-carbon-cycle-feedbacks-could-make-global-warming-worse/
Our global industrial activity emits more CO2 than a super volcano with no signs of slowing down on top of observable CO2 feedback loops going off. Ocean heat content and acidity is rising as it did in the Permian. So I don't think its an unfair claim to make.
Gemini884 t1_j3qd8eg wrote
Did you not read all of my links?
https://nitter.lacontrevoie.fr/hausfath/status/1572317492781125632#m
https://nitter.kavin.rocks/JoeriRogelj/status/1424743837277294603
There's not enought available fossil fuel resources to match the total amount emitted during that event. Do you think we will keep emitting at current rate for many more hundreds of years?https://www.nature.com/articles/s41467-021-22298-7
https://eos.org/articles/how-modern-emissions-compare-to-ancient-extinction-level-events
https://nitter.lacontrevoie.fr/hausfath/status/1280282554889760768#m
Content_Date_318 t1_j3r0tcc wrote
There's more than enough fossil fuels though to kick off feedback loops in the earths climate. Feedback loops such as carbon release from forest fires, albedo loss from earth losing reflective surfaces, permafrost melt and a couple others I'm missing.
​
Not only that, but the CO2 ppm we are currently sitting at is roughly the same as when the permian started, which is why it's no coincidence we are seeing earths systems begin to behave in similar ways as during the outset of the permian as we have filled the atmosphere full of carbon.
Gemini884 t1_j3r4evr wrote
Why didn't you read any of my links? Don't talk to me unless you'venread every single one. You don't understand what you're talking about.
​
There is no evidence for projected warming <3-4C of any tipping points that significantly change the warming trajectory. Read ipcc report and read what scientists say instead of speculating.
https://nitter.kavin.rocks/MichaelEMann/status/1495438146905026563
https://nitter.kavin.rocks/hausfath/status/1571146283582365697#m
"Some people will look at this and go, ‘well, if we’re going to hit tipping points at 1.5°C, then it’s game over’. But we’re saying they would lock in some really unpleasant impacts for a very long time, but they don’t cause runaway global warming."- Quote from Dr. David Armstrong Mckay, the author of one of recent studies on the subject to Newscientist mag. here are explainers he's written before-
https://climatetippingpoints.info/2019/04/01/climate-tipping-points-fact-check-series-introduction/ (introduction is a bit outdated and there are some estimates that were ruled out in past year's ipcc report afaik but articles themselves are more up to date)
Content_Date_318 t1_j3r83gg wrote
But the thing is, we aren't stopping at 2c. We will burn carbon based energy sources as long as our current system exists at increasing rates until they're gone, which is backed up by our behavior since the outset of the industrial revolution.
​
A bunch of these people you're linking are making assumptions that our carbon emitting industrial activity will cease, which is wrong unless a revolution to change our economic system happens.
​
Also in those articles those scientists talk about how they have LOW CONFIDENCE due to a variety of factors in their modeling around several feedback loops. Read your own stuff please
Gemini884 t1_j3rar5g wrote
But you literally made the assumption that warming is going to be worse than what models project, and that agw "will probably be worse than the Permian extinction event. ".
​
Do you think you know more than the climate scientists I've linked? Our emissions are projected to peak and start declining around 2030 in current policy scenario.
https://nitter.kavin.rocks/KHayhoe/status/1539621976494448643#m
https://nitter.kavin.rocks/hausfath/status/1511018638735601671#m
https://climateactiontracker.org/
https://nitter.kavin.rocks/MichaelEMann/status/1432786640943173632#m
You don't understand what you've read. And I suspect that you did not read everything I've linked.
Content_Date_318 t1_j3rbwru wrote
Yes, I treat the models like they're supposed to be treated, as a good reference and solid idea on how things turn out. They don't perfectly simulate reality for the reasons I have outlined.
​
I do not listen to climate panel agreements anymore because they have been shown to be worth less than the paper they are written on outside of a few cases. I've been following climate panels since the 90s and we've nearly doubled CO2 emissions since then. There is no meaningful interest in reducing emissions for a myriad of factors which can be boiled down to, we will not ignore cheap energy when its so vital to economic growth.
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Gemini884 t1_j3xjmsb wrote
Why are you spreading misinformation that's not in line with ipcc report scientific consensus? You know that it's an irresponsible thing to do.
Content_Date_318 t1_j3xmyn1 wrote
I am not spreading misinformation. I am making people aware of the limitations of our scientific modeling and stating clearly the present course we are on. I have given you more than enough to back up my statements which obviously is a bother to you, which is a personal problem I'm afraid. Have a nice life.
Gemini884 t1_j3xqmen wrote
I literally pointed out where you are wrong multiple times. You did not read all of the links I sent you which is your problem. You should listen to actual climate scientists instead of morons from r/collapse.
​
>I treat the models like they're supposed to be treated, as a good reference and solid idea on how things turn out.
I repeat, you literally made the assumption that warming is going to be worse than what models project when it can go both ways. There is little evidence that climate change is worse than we thought, nor that assessments are downplaying the risks.
You also claimed that models "don't account for permafrost thaw or dynamic vegetation feedback" which is not true because they do account for these things.
"climate panel agreements" Yeah, you totally can not read. I was talking talking about current policies(as in, policies that are already implemented, not pledges made at COPs).
"Also in those articles those scientists talk about how they have LOW CONFIDENCE" You just took words out of context. Point me to the article and paragraph where these words are.
Content_Date_318 t1_j3xsug8 wrote
I'm sorry, but we are going in circles. I will not be replying anymore. I literally linked you your own article with climate scientists saying what particulars in their simulations they have high and low confidence on which is predicated on our understanding of certain mechanics in earths system which we are still learning much about.. Not only that the lower pathways rely on us cutting emissions, which I am telling you isn't happening unless there are major changes to our growth based economic system as it is addicted to the cheap energy carbon based fuels provide.
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Work on your reading comprehension and read your own stuff please.
Gemini884 t1_j3y0f2a wrote
Yes, models aren't 100% accurate and there are uncertainties, please answer how does that justify your assumption that they somehow underestimate future warming? It's not a fair assumption to make, since warming tends to track middle-of-the-range estimates, climate models in previous ipcc reports neither systematically overestimated nor underestimated warming over the period of their projections.
https://nitter.kavin.rocks/hausfath/status/1557421984484495362
https://nitter.kavin.rocks/Knutti_ETH/status/1554473710404485120
Climate policy changes have already reduced projected warming from >4c to <3c by the end of century. That's a current policy scenario, it's even lower if you count in pledges and commitments.
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https://nitter.kavin.rocks/MichaelEMann/status/1432786640943173632#m
https://nitter.kavin.rocks/hausfath/status/1511018638735601671#m
https://nitter.kavin.rocks/KHayhoe/status/1539621976494448643#m
Gemini884 t1_j3y4jum wrote
>I will not be replying anymore
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It's funny how you can just do that on the internet(on top of having no proper punishment or any consequences for disinformation whatsoever).
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Gemini884 t1_j3npjq7 wrote
You did not even read the article. tldr- (https://www.reddit.com/r/science/comments/106tuzk/comment/j3lh3nb/?utm_source=reddit&utm_medium=web2x&context=3
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Also,
Information on marine biomass decline from recent ipcc report: "Global models also project a loss in marine biomass (the total weight of all animal and plant life in the ocean) of around -6% (±4%) under SSP1-2.6 by 2080-99, relative to 1995-2014. Under SSP5-8.5, this rises to a -16% (±9%) decline. In both cases, there is “significant regional variation” in both the magnitude of the change and the associated uncertainties, the report says." phytoplankton in particular is projected to decline by ~10% in worst-case emissions scenario.
https://www.carbonbrief.org/in-depth-qa-the-ipccs-sixth-assessment-on-how-climate-change-impacts-the-world/#oceanshttps://
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WeLLrightyOH t1_j3k0x4f wrote
For a serious answer, I believe it represents an actual word or term that was directly spoken in the item that the title refers to. Essentially it’s a quote really.
nitrohigito t1_j3k33hq wrote
To clarify this isn't their subjective remark.
Chance_Implausible t1_j3k3ujx wrote
Well folks, it's been nice knowing you.
subzero112001 t1_j3kkqpm wrote
No it hasn’t. Hence why this has happened. :’(
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berkelbees t1_j3l2i9h wrote
Deep water currents are so important. I learned this in an oceanography class that I took in 1992. I also learned that scientists had been looking at the slowing of these currents since the 1980’s.
maxToTheJ t1_j3l0dr3 wrote
I am starting to suspect our illicited mass climate change might kill alll the fish before we could fish them to extinction
daytonakarl t1_j3lhxlp wrote
Commercial fishing is going to give it a bloody good shot though
BurnerAcc2020 t1_j3lj8wo wrote
https://www.nature.com/articles/s41467-020-15708-9
>Significant biomass changes are projected in 40%–57% of the global ocean, with 68%–84% of these areas exhibiting declining trends under low and high emission scenarios, respectively.
>
>...Climate change scenarios had a large effect on projected biomass trends. Under a worst-case scenario (RCP8.5, Fig. 2b), 84% of statistically significant trends (p < 0.05) projected a decline in animal biomass over the 21st century, with a global median change of −22%. Rapid biomass declines were projected across most ocean areas (60°S to 60°N) but were particularly pronounced in the North Atlantic Ocean. Under a strong mitigation scenario (RCP2.6, Fig. 2c), 68% of significant trends exhibited declining biomass, with a global median change of −4.8%. Despite the overall prevalence of negative trends, some large biomass increases (>75%) were projected, particularly in the high Arctic Oceans.
>
>Our analysis suggests that statistically significant biomass changes between 2006 and 2100 will occur in 40% (RCP2.6) or 57% (RCPc8.5) of the global ocean, respectively (Fig. 2b, c). For the remaining cells, the signal of biomass change was not separable from the background variability.
https://www.nature.com/articles/s41558-021-01173-9
>Mean projected global marine animal biomass from the full MEM ensemble shows no clear difference between the CMIP5 and CMIP6 simulations until ~2030 (Fig. 3). After 2030, CMIP6-forced models show larger declines in animal biomass, with almost every year showing a more pronounced decrease under strong mitigation and most years from 2060 onwards showing a more pronounced decrease under high emissions (Fig. 3). Both scenarios have a significantly stronger decrease in 2090–2099 under CMIP6 than CMIP5 (two-sided Wilcoxon rank-sum test on annual values; n = 160 for CMIP6, 120 for CMIP5; W = 12,290 and P < 0.01 for strong mitigation, W = 11,221 and P = 0.016 for high emissions).
>
>For the comparable MEM ensemble (Extended Data Fig. 3), only the strong-mitigation scenario is significantly different (n = 120 for both CMIPs; W = 6,623 and P < 0.01). The multiple consecutive decades in which CMIP6 projections are more negative than CMIP5 (Fig. 3b and Extended Data Fig. 3b) suggest that these results are not due simply to decadal variability in the selected ESM ensemble members. Under high emissions, the mean marine animal biomass for the full MEM ensemble declines by ~19% for CMIP6 by 2099 relative to 1990–1999 (~2.5% more than CMIP5), and the mitigation scenario declines by ~7% (~2% more than CMIP5).
There was even a paper which found that even if the worst-case emission trajectory in those studies somehow continues until 2300 and gets to something like 12 degrees by 2300 (which would necessarily require the world not to collapse until then, btw, as otherwise the emissions wouldn't have anywhere to come from), about half the species in the ocean would still survive.
BurnerAcc2020 t1_j3lh3nb wrote
So, out of the 33 comments so far, literally nobody read the article far enough to realize that, according to the researchers, this only happens:
a) under worst-case warming (code word for continually increasing emissions);
b) by 2300;
c) Even then, it only happens to the Southern Meridional Overturning Circulation, and not to the Atlantic one?
r/science at its "best", as usual.
CornucopiaOfDystopia t1_j3lypo2 wrote
Literally not even what your own quoted excerpt from elsewhere in this thread states that, so why are you posting this? What do you think is meant by your own quoted portion which states,
>In the present study, the AMOC collapse reverses the warming seen in the smooth climate change scenarios, generating an average fall in temperature of 3.4 °C by 2080, accompanied by a substantial reduction in rainfall (−123 mm during the growing season.
Why are you deliberately and confidently misrepresenting the science on this, in multiple parts of this thread?
screendoorblinds t1_j3m2ot3 wrote
Not who you're replying to but I don't see that quote in their post or the article - I think they are referencing this section "These researchers analyzed projections from three dozen climate models and found that the Atlantic Meridional Overturning Circulation and the Southern Meridional Overturning Circulation will slow by as much as 42 percent by 2100. The simulations suggest that under worst-case warming, the SMOC could cease entirely by 2300."
CornucopiaOfDystopia t1_j3m31nj wrote
A good clarification, thank you. However, that commenter is very clearly implying that there is no concern to be had at all before 2300, which is plainly not what the relevant studies have found. Significant dangers exist well before total shutdown of the current, and it’s misleading at best to imply that the concern is only relevant if the collapse is complete.
Alternative-Flan2869 t1_j3ky62x wrote
This all does not sound good at all, especially with climate deniers gaining ground a ross the globe.
grewapair t1_j3mdseg wrote
To solve this, you would have to A) increase energy prices to replace carbon sources with renewable sources thereby increasing inflation, and B) stop the purchase of products from China and India, who would remain the world's biggest emittters, thereby increasing inflation.
Not saying we shouldn't do it, but it's going to dramatically lower our standard of living right now, to preserve the standard of living 77 years from now. That's the problem with this, the harms are so far off, and the costs are so high, it is difficult to rally much support.
crazyhadron t1_j3n1e1s wrote
Yeah, stop buying stuff from India until our government enacts similar stringent environmental policies. Exports don't really help the common person, and we're more of a service-based economy anyways.
thecowintheroom t1_j3lg6j9 wrote
Let’s get to work y’all
It’s no longer a question.
Commitment coming from America
“Our analysis also shows that reducing greenhouse gas emissions now can prevent this complete shutdown of the deep circulation in the future,” he said.
daytonakarl t1_j3lilkt wrote
>Commitment coming from America
Hmmmm, we'll see...
thecowintheroom t1_j3lj8hx wrote
We’ll see Europe continue complaining about energy independence.
We’ll see China expand into the South China Sea.
We’ll see Russia continue to extract and use oil because the Russian Orthodox Church says that oil is gods gift to Russia and there are no harmful effects from its use.
But yes you will see america lead the earth into a renewable future.
Good luck with climate change.
_CMDR_ t1_j3l9ydb wrote
The endgame of that is Permian Extinction. Bad at a level we would have a hard time comprehending.
Gemini884 t1_j3nocvf wrote
Read IPCC report on impacts and read what climate scientists say instead of speculating-
https://nitter.kavin.rocks/MichaelEMann/status/1432786640943173632#m
https://nitter.42l.fr/ClimateAdam/status/1553757380827140097
https://nitter.42l.fr/GlobalEcoGuy/status/1477784375060279299#m
https://nitter.42l.fr/JacquelynGill/status/1553503548331249664#m
https://nitter.kavin.rocks/hausfath/status/1533875297220587520#m
https://nitter.42l.fr/JacquelynGill/status/1513918579657232388#m
https://nitter.42l.fr/waiterich/status/1477716206907965440#m
​
Information on marine biomass decline from recent ipcc report: "Global models also project a loss in marine biomass (the total weight of all animal and plant life in the ocean) of around -6% (±4%) under SSP1-2.6 by 2080-99, relative to 1995-2014. Under SSP5-8.5, this rises to a -16% (±9%) decline. In both cases, there is “significant regional variation” in both the magnitude of the change and the associated uncertainties, the report says." phytoplankton in particular is projected to decline by ~10% in worst-case emissions scenario.
https://www.nature.com/articles/s41558-021-01173-9/figures/3
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It is likely that the proportion of all species at very high risk of extinction (categorised as “critically endangered” by the IUCN Red List) will reach 9% (maximum 14%) at 1.5C, 10% (18%) at 2C, 12% (29%) at 3C, 13% (39%) at 4C and 15% (48%) at 5C, the report says.
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_CMDR_ t1_j3nq9x0 wrote
These are all consistent with Permian extinction outcomes as that took hundreds of thousands of years and this is taking decades.
Gemini884 t1_j3nuv8j wrote
There's not enought available fossil fuel resources to match the total amount emitted during that event. Do you think we will keep emitting at current pace for many more hundreds of years?
DeepHistory t1_j3mr5kz wrote
Good research. But don't just doomscroll, do something about it.
- Vote, volunteer, and fund raise for viable environmental candidates.
- Our personal choices DO matter when we act together - have less kids (if you live in a wealthy country), go vegan, make your next car an EV, divest from polluting corporations.
- Get your family, friends, and community to join you in the above.
Spocks-Nephew t1_j3kuz0k wrote
Polar bears are making a huge comeback too.
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WillLurk4Food t1_j3l1e9r wrote
Yeah, I know. We're doomed. I get it.
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ProceedOrRun t1_j3kjz0m wrote
But it appears we're collectively failing to take it seriously, or more to the point the establishment isn't taking it seriously and we're being bullshitted into having to live with it.
river_tree_nut t1_j3km49m wrote
Would you feel better if the “quotes” were removed from the term disaster?
South5 t1_j3khtod wrote
It has been spoken about for many years that if the Atlantic sea currents were to alter that northern europe would be vastly colder than it is currently.
We have very mild winters in the uk because of the heat of the ocean, we could be like canada or russia in winter without this convection current.