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Old 02-12-2019, 09:28   #1156
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Re: La Vagabonde's crossing

just for fun, i looked at the speed of a low which recently came off Newfoundland

speed every 12 hrs
10kts
33kts
21kts
26kts
16kts

average 21kts

that's not necessarily 'representative', just a random low I picked.

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Originally Posted by Exile View Post
enough to avoid an unpredictable, large, and fast moving tropical storm/hurricane.
there are definitely risks, potentially systems that you just can't manage to avoid. How big those risks are I really could not say. Certainly lower with improved forecasting and greater boat speed (and a competent skipper), Certainly higher with hurricane systems than others, but I know people who have lost boats near the Azores mid-summer.

We chatted about Lenny up thread - I would love to see how (well or poorly) the forecasting (esp euro model) handled that today. Scared the **** out of me back in the day.
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Old 02-12-2019, 09:29   #1157
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Re: La Vagabonde's crossing

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So, she didn't fly over? Or the jet mysteriously didn't emit carbon?
Not that I believe it's a problem in the first place, but....
Great example. If basic facts don't appear in media outlets of the reader's choosing they didn't happen. This applies both ways of course.
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Old 02-12-2019, 09:43   #1158
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Re: La Vagabonde's crossing

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Originally Posted by Exile View Post
Finding balanced news or opinion reporting is exactly the problem. So is confirmation bias. These days you have to force yourself to read credible publications and informed opinions that don't conform with your own point of view to try and achieve any sort of objectivity or "balance." Unfortunately, far too many people evaluate the "credibility" of opinions contrary to their own on purely personal, subjective factors. In the extreme, you have far too many people who I have no doubt are sincere in their beliefs, but seem genuinely surprised and therefore personally offended when confronted with contrary points of view. Once the personalization, labeling, and name-calling starts, an otherwise well-intentioned advocate has lost the debate. Or more to the point, has lost the ability to influence opinion on the subject.
I've looked but haven't found any "credible" reports that support the idea that the current climate change is normal and not caused by man.
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Old 02-12-2019, 09:48   #1159
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Re: La Vagabonde's crossing

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I'm no scientist but it seems obvious to me that the cold melt water will flow over top of the warm saline water. Therefore, a cold region where the melt water meets the Gulf Stream.
Well we evidently did have a "scientist" here (Maapallo) state that "Salinty gradients are what drives the gulf stream".
This is just not consistent with existing science regarding driving forces of the five major gyres of the world. Those driving forces primarily include the Coriolis Effect and wind stress. Salinity gradients have indeed been shown to alter the gyres as a secondary effect from what I've read, albiet a serious secondary effect.

I would simply like to see anything (study, paper, Wiki...) that points to salinity gradients as "what drives the gulf stream".
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Old 02-12-2019, 09:53   #1160
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La Vagabonde's crossing

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Originally Posted by bcboomer View Post
I've looked but haven't found any "credible" reports that support the idea that the current climate change is normal and not caused by man.


Really? The charts depicting ocean levels and temps historically didn’t do that for you?
The flip side is that I’d bet depending on how you determine credible, the flip side of that is true too.

I’m not arguing against you, I have believed that burning fossil fuel is stupid since the early 70’s, mostly because I imagine one day people will be sitting around and say unbelievingly, Can you believe those idiots back in the day used to burn such an important raw material, I mean just burn it, can you imagine?

Now don’t get all upset about me bringing up the charts, it was just meant to say that the issue is so complex it’s likely that there isn’t one issue, my personal belief is that yes mankind is greatly affecting the climate, just look at how much heat we release from our activities, it’s astonishing and changing sources of power away from fossil fuel isn’t going to reduce that heat.
In my opinion we need to reduce fossil fuel consumption, but we also need to be more efficient in how we use power, I’m convinced we could become far more efficient and not give up anything. We could still have our personal transportation, but it wouldn’t be 6,000 lb behemoths.
Even the tire wear from those monsters has a very serious effect on the environment, huge amounts of rubber powder is being introduced into the water supply from tire wear, and of course it’s way more than that, merely converting to electricity may make people feel good, but in truth I believe we need to do far more than that.
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Old 02-12-2019, 10:03   #1161
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Re: La Vagabonde's crossing

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Originally Posted by DDouglasone View Post
Thank-you!

Anyone genuinely questioning the Climate Change debate should first and foremost understand we are currently in a receding glacial maximum.
Remember the "Little Ice Age" experienced in the 1700's anyone or the warming during the 1400's aka The Renaissance?

Yeah right science forgot all about that. You so smart!

https://skepticalscience.com/coming-out-of-little-ice-age.htm

Just look at the Younger-Dryas period 13-14kya when after 5-6 thousands yrs of receding glaciers, boom! 300 yrs and the glaciers advanced down to New York City and were a mile high!

Oh yeah that’s right...those dumb scientists!
https://skepticalscience.com/climate-change-little-ice-age-medieval-warm-period.htm



Just one single volcanic eruption throws up more C02 than man AND woman has ever produced since the discovery of fire! 😁

Oops they left that one out too!
https://skepticalscience.com/volcanoes-and-global-warming.htm

Why are the polar caps on Mars receding as well?

https://skepticalscience.com/global-warming-on-mars.htm

No one likes pollution but to assert what Climate Hoaxers claim is just plain fiction.

https://skepticalscience.com/evidence-for-global-warming.htm

Nothing wrong with cleaning up our act, as we should, but the lunacy I suspect is mere projection because precious little is done by those who advocate this in favor of using my money to "fix it"!
https://skepticalscience.com/climate-scientists-in-it-for-the-money.htm

I know this guy won’t read the links to real facts but his opinions are just that. Try reading a little about the science.
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Old 02-12-2019, 10:05   #1162
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Re: La Vagabonde's crossing

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Originally Posted by Exile View Post
Finding balanced news or opinion reporting is exactly the problem. So is confirmation bias. These days you have to force yourself to read credible publications and informed opinions that don't conform with your own point of view to try and achieve any sort of objectivity or "balance." Unfortunately, far too many people evaluate the "credibility" of opinions contrary to their own on purely personal, subjective factors...
... Once the personalization, labeling, and name-calling starts, an otherwise well-intentioned advocate has lost the debate. Or more to the point, has lost the ability to influence opinion on the subject.
Good points. However, even reading/hearing both sides of a debate, may not really influence us, very much.

Whenever we engage in controversial debates, we all tend to overrate the power of arguments, we find personally convincing, and wrongly think the other side will be swayed. Anyone who has argued with an opinionated friend about climate change, or gun control, knows it is often impossible to sway someone with strong views.

That’s, in part, because our brains work hard to ensure the integrity of our worldview. We seek out information to confirm what we already know, and are dismissive, or avoidant, of facts that are hostile to our core beliefs. What both sides fail to understand, is that they're arguing a point that their opponents have not only already dismissed, but may be inherently deaf to.

In 2017, researchers at Duke, NYU, and Princeton, ran an experiment* where they paid a large sample of Democratic and Republican Twitter users to read more opinions from the other side.
It was, in other words, a test of the simple theory:

Does hearing out the other side make us less polarized, or more?
They found no evidence that inter-group contact on social media reduces political polarization.

In fact, the results of the month-long exposure to popular, authoritative voices, from the other side of the aisle, was an increase in issue-based polarization.

“We find that Republicans, who followed a liberal Twitter bot, became substantially more conservative post treatment,” write the authors. “Democrats exhibited slight increases in liberal attitudes, after following a conservative Twitter bot, although these effects are not statistically significant.”
Republicans in the experiment actually grew more conservative, over the course of the test. Liberals in the experiment grew slightly more liberal.

The study was tuned to tell us what happened when people heard other opinions; it wasn’t designed to illuminate why it happened. But Bail offered three theories.

The first possibility, he said, was counter-arguing. If you’re a liberal browsing Twitter, and you’re suddenly confronted with a Mitch McConnell tweet touting the benefits of tax cuts and the harms of Obamacare, your mental response isn’t to think, “Hmm, that McConnell makes some good points.” It’s to instantly come up with an argument for why he’s wrong.

No one is better at convincing us of a position than, well, us, and so as we see and instantly reject the arguments made by our political opponents, we become more convinced in the rightness of what we initially believed, and we come up with more reasons to believe it.

Another possibility turns on the differing values of Democrats and Republicans. A strain of research called moral foundations theory shows that Democrats tend to construct their moral lives atop values like diversity, change, and fairness, while Republicans build their moral frameworks atop values like authority, tradition, and certainty.
Perhaps the reason Republicans reacted more strongly to being confronted with contrary views, is that they’re more offended by challenges to authority, while Democrats have built more of an identity around openness to change.
The problem with that explanation, in my view, is that it seems to predict Democrats changing their views, which didn’t happen.

A third possibility is that the participants were taking cues from elites, including negative cues. A low-information Republican, who didn’t know that much about what Democrats actually thought, might find themselves more horrified by the liberal worldview when exposed to it regularly. If you’re not that interested in politics, and your image of a Democrat is Hillary Clinton or Barack Obama, seeing a lot of tweets about abolishing ICE or kneeling during the national anthem might push you further right.

I tend to believe a variant of the first explanation. “Republican” is an identity. “Democrat” is an identity. When you log on to Twitter (or CF), and read someone attacking the people you admire, the people you ally with, the people you see as your group, you become defensive of your side, and angry at the critics.

* “Exposure to opposing views on social media can increase political polarization” ~ by Christopher A. Bail et al
https://www.pnas.org/content/115/37/9216.full

In another recent study, Jan Gerrit Voelkel & Robb Willer found, in a nationally representative sample, that conservatives would be more willing to support a hypothetical liberal candidate for president, if that candidate used language that reflected conservative values. For instance, conservatives who read that the candidate’s “vision for America is based on respect for the values and traditions that were handed down to us...” were more likely to say they supported him, than when the candidate’s message was framed with liberal buzzwords. In other words, framing mattered more than policy.
So, if a conservative wanted to convince a liberal to support higher military spending, he shouldn't appeal to patriotism. He should say something like, "Through the military, the disadvantaged can achieve equal standing, and overcome the challenges of poverty and inequality."
Of course, there's only so much that reframing in terms of values can do. It can't turn an anti-Obamacare conservative into a universal health-care liberal, but it might soften his stance, and get him to listen to counter-arguments.

“Resolving the Progressive Paradox: Conservative Value Framing of Progressive Economic Policies Increases Candidate Support” ~ by Jan Gerrit Voelkel & Robb Willer
https://papers.ssrn.com/sol3/papers....act_id=3385818
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Old 02-12-2019, 10:05   #1163
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Re: La Vagabonde's crossing

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Originally Posted by bcboomer View Post
I've looked but haven't found any "credible" reports that support the idea that the current climate change is normal and not caused by man.
You just made my point. I'd suggest looking harder.
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Old 02-12-2019, 10:55   #1164
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Re: La Vagabonde's crossing

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Originally Posted by GordMay View Post
Good points. However, even reading/hearing both sides of a debate, may not really influence us, very much.

* * *
While I don't agree with some of its generalizations about Repubs & Dems (rather biased stereotyping), I thought overall this was an excellent post Gord. (as is your habit & pattern ) Among other basic human traits, it reinforces why tribalism is such a predominant one, and therefore why partisanship, polarization, and bias is so difficult to overcome.

But it does trouble me when the response from those who disagree is more along the lines of shock/surprise -- or worse righteous indignation -- as opposed to more reasoned retort. It suggests people are no longer bothering to engage with each other, a state of affairs which has proven itself rather dangerous historically. And I still hold out hope that, while overall opinions & beliefs may never be changed as the study you cite adeptly explains, a better understanding of where the opposition is coming from might just lead to some compromise. With our democratic systems of governance, only compromise will move issues forward, whether some like that concept or not. The absence of compromise runs the risk of a move towards autocracy/tyranny and govt by fiat as opposed to consensus, a result which many feel is far more dangerous to basic human rights than warming temps.
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Old 02-12-2019, 11:14   #1165
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Re: La Vagabonde's crossing

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Originally Posted by Exile View Post
6. Climate change is real. The human role is likely significant. It may not be too late but the socioeconomic/political remedies being proposed have time & again proven themselves worse for humankind than the forecasted environmental harm.



From one of GT's (and others) latest pronouncements:



"That action must be powerful and wide-ranging. After all, the climate crisis is not just about the environment. It is a crisis of human rights, of justice, and of political will. Colonial, racist, and patriarchal systems of oppression have created and fueled it. We need to dismantle them all. Our political leaders can no longer shirk their responsibilities."



https://www.project-syndicate.org/co...-et-al-2019-11



Talk about alienating a huge segment of the population that are otherwise sympathetic to the environmental issue but don't want to have anything to do with the extreme politics that seems to be required to be "subscribed." I'll stick with more rational subscriptions thanks.


Reality doesn't care to what you are subscribed
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Old 02-12-2019, 11:24   #1166
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Re: La Vagabonde's crossing

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Originally Posted by crankysailor View Post
Reality doesn't care to what you are subscribed
Who's reality? As Gord's recent post ably pointed out, reality is all too often in the eye of the beholder. Reality should always be questioned, not blindly adhered to.
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Old 02-12-2019, 11:31   #1167
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Re: La Vagabonde's crossing

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Originally Posted by jzk View Post
She is telling people that ecosystems are collapsing and a mass extinction event is underway. Currently, the amount of children that live past age 10 is directly proportional to fossil fuel use. Fossil fuel is not just a money making scheme for a segment of society, but rather how most of society eats and moves around.

A super cool trip for a kid to experience. But she had Nikki fly back from Europe to join the team cancelling out any "benefit" from her not flying. Other than promoting LV that is.
we all know what she is telling kids ( and the rest who are prepared to listen ) what i asked was where you heard the sensationalist claim that kids are suffering etc etc ???????
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Old 02-12-2019, 11:32   #1168
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Re: La Vagabonde's crossing

Quote:
Originally Posted by GordMay View Post
Good points. However, even reading/hearing both sides of a debate, may not really influence us, very much.

Whenever we engage in controversial debates, we all tend to overrate the power of arguments, we find personally convincing, and wrongly think the other side will be swayed. Anyone who has argued with an opinionated friend about climate change, or gun control, knows it is often impossible to sway someone with strong views.

That’s, in part, because our brains work hard to ensure the integrity of our worldview. We seek out information to confirm what we already know, and are dismissive, or avoidant, of facts that are hostile to our core beliefs. What both sides fail to understand, is that they're arguing a point that their opponents have not only already dismissed, but may be inherently deaf to.

In 2017, researchers at Duke, NYU, and Princeton, ran an experiment* where they paid a large sample of Democratic and Republican Twitter users to read more opinions from the other side.
It was, in other words, a test of the simple theory:

Does hearing out the other side make us less polarized, or more?
They found no evidence that inter-group contact on social media reduces political polarization.

In fact, the results of the month-long exposure to popular, authoritative voices, from the other side of the aisle, was an increase in issue-based polarization.

“We find that Republicans, who followed a liberal Twitter bot, became substantially more conservative post treatment,” write the authors. “Democrats exhibited slight increases in liberal attitudes, after following a conservative Twitter bot, although these effects are not statistically significant.”
Republicans in the experiment actually grew more conservative, over the course of the test. Liberals in the experiment grew slightly more liberal.

The study was tuned to tell us what happened when people heard other opinions; it wasn’t designed to illuminate why it happened. But Bail offered three theories.

The first possibility, he said, was counter-arguing. If you’re a liberal browsing Twitter, and you’re suddenly confronted with a Mitch McConnell tweet touting the benefits of tax cuts and the harms of Obamacare, your mental response isn’t to think, “Hmm, that McConnell makes some good points.” It’s to instantly come up with an argument for why he’s wrong.

No one is better at convincing us of a position than, well, us, and so as we see and instantly reject the arguments made by our political opponents, we become more convinced in the rightness of what we initially believed, and we come up with more reasons to believe it.

Another possibility turns on the differing values of Democrats and Republicans. A strain of research called moral foundations theory shows that Democrats tend to construct their moral lives atop values like diversity, change, and fairness, while Republicans build their moral frameworks atop values like authority, tradition, and certainty.
Perhaps the reason Republicans reacted more strongly to being confronted with contrary views, is that they’re more offended by challenges to authority, while Democrats have built more of an identity around openness to change.
The problem with that explanation, in my view, is that it seems to predict Democrats changing their views, which didn’t happen.

A third possibility is that the participants were taking cues from elites, including negative cues. A low-information Republican, who didn’t know that much about what Democrats actually thought, might find themselves more horrified by the liberal worldview when exposed to it regularly. If you’re not that interested in politics, and your image of a Democrat is Hillary Clinton or Barack Obama, seeing a lot of tweets about abolishing ICE or kneeling during the national anthem might push you further right.

I tend to believe a variant of the first explanation. “Republican” is an identity. “Democrat” is an identity. When you log on to Twitter (or CF), and read someone attacking the people you admire, the people you ally with, the people you see as your group, you become defensive of your side, and angry at the critics.

* “Exposure to opposing views on social media can increase political polarization” ~ by Christopher A. Bail et al
https://www.pnas.org/content/115/37/9216.full

In another recent study, Jan Gerrit Voelkel & Robb Willer found, in a nationally representative sample, that conservatives would be more willing to support a hypothetical liberal candidate for president, if that candidate used language that reflected conservative values. For instance, conservatives who read that the candidate’s “vision for America is based on respect for the values and traditions that were handed down to us...” were more likely to say they supported him, than when the candidate’s message was framed with liberal buzzwords. In other words, framing mattered more than policy.
So, if a conservative wanted to convince a liberal to support higher military spending, he shouldn't appeal to patriotism. He should say something like, "Through the military, the disadvantaged can achieve equal standing, and overcome the challenges of poverty and inequality."
Of course, there's only so much that reframing in terms of values can do. It can't turn an anti-Obamacare conservative into a universal health-care liberal, but it might soften his stance, and get him to listen to counter-arguments.

“Resolving the Progressive Paradox: Conservative Value Framing of Progressive Economic Policies Increases Candidate Support” ~ by Jan Gerrit Voelkel & Robb Willer
https://papers.ssrn.com/sol3/papers....act_id=3385818
The very best post I ever read on any forum
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Old 02-12-2019, 11:33   #1169
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Re: La Vagabonde's crossing

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Originally Posted by OldKetch View Post
Please spend 2 minutes on google before ranting

"Children are increasingly suffering anxiety and grief about climate change, British psychologists said on Thursday, advising parents to discuss the issue in an age-appropriate way."

https://www.reuters.com/article/us-b...-idUSKBN1W42CF

And these guys are on the side of GT
https://www.climatepsychologyalliance.org/
if any kids are suffering anxiety where are the parents ? somewhere in denial ???
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Old 02-12-2019, 11:39   #1170
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Re: La Vagabonde's crossing

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Well we evidently did have a "scientist" here (Maapallo) state that "Salinty gradients are what drives the gulf stream".
This is just not consistent with existing science regarding driving forces of the five major gyres of the world. Those driving forces primarily include the Coriolis Effect and wind stress. Salinity gradients have indeed been shown to alter the gyres as a secondary effect from what I've read, albiet a serious secondary effect.

I would simply like to see anything (study, paper, Wiki...) that points to salinity gradients as "what drives the gulf stream".
I had not wanted to comment further - despite a lot of really flawed representations of what science says being posted - because this thread is not about the ice age cycles or climate change. I had tried to limited my post just to effects that might change weather patterns in the North Atlantic down the road. And the lenth of my post was embarrassing - difficult to be short on such demanding topics (thanks for lots of positive feedback, though).

But since I'm being challenged, here we go. I am not happy that this thread is deteriorating once again, but maybe that is because the voyage is ending and there is little routing to discuss. Probably not going to short again - apologies. Don't know why you put "scientist" into quotation marks.

Perhaps there is a bit of misunderstanding. For surface currents, such as those that sailors deal with, wind is of course the major factor, and of course they are shaped by coriolis forces as are all flows of some size. But these wind-driven currents cannot explain the large flows of water in much larger depth - down to 1.2 km going north, much deeper going south - that constitute the Atlantic meridonial overturning circulation, the thermohaline circulation in the Atlantic that transports all that energy north. As the name already says, these are largely driven by thermo and haline, i.e. temperature and salinity gradients, while of course being influenced by - but not sustained by - winds and coriolis. Overall it is a complex phenomon with eddies and flows across all scales, very fascinating, a product of turbulent complexities.

Wikipedia explains it quite well, eg under "thermohaline circulation" (I have to shorten by a lot): "In the deep ocean, the predominant driving force is differences in density, caused by salinity and temperature variations (increasing salinity and lowering the temperature of a fluid both increase its density). There is often confusion over the components of the circulation that are wind and density driven. [...] The thermohaline circulation is mainly driven by the formation of deep water masses in the North Atlantic and the Southern Ocean caused by differences in temperature and salinity of the water. [...]".

Or wikipedia under "Atlantic meridonial overturning circulation": "The Atlantic meridional overturning circulation (AMOC) is the zonally-integrated component of surface and deep currents in the Atlantic Ocean. It is characterized by a northward flow of warm, salty water in the upper layers of the Atlantic, and a southward flow of colder, deep waters that are part of the thermohaline circulation. These "limbs" are linked by regions of overturning in the Nordic and Labrador Seas and the Southern Ocean. The AMOC is an important component of the Earth's climate system, and is a result of both atmospheric and thermohaline drivers."

The melting of Greenland - which could cross the threshold of no-return already at less than 2 deg C of warming (7m of sea level rise - but would luckily take thousands of years to melt completely) - could be messing up the salinity balances in the deep water formation zones, slowing down the circulation and heat transport, which in turn is a major factor in the weather systems arising.

Here are scientific reviews: July 2019, Weijer et al., Journal of Geophysical Research: Oceans, 124, "Stability of the Atlantic Meridional Overturning Circulation: A Review and Synthesis": "A key process in the maintenance of the AMOC is thought to be deep convection in the subpolar North Atlantic Ocean, in particular the Labrador and Nordic Seas (e.g., Marshall & Schott, 1999). Here, wintertime cooling of relatively salty surface waters leads to convective instabilities that drains heat from the water column and produces cold and salty North Atlantic Deep Water (NADW). The salinity of the upper North Atlantic is significantly higher than in other basins, a salinity surplus that is maintained partly by a net excess of evaporation over precipitation, river runoff, and ice melt (Emile‐Geay et al., 2003; Schmitt, 2008; Warren, 1983) and partly by oceanic transports, in particular, the import of salty Indian Ocean water through Agulhas Leakage (De Ruijter et al., 1999; Gordon, 1986). These processes precondition the Atlantic for deep convection (e.g., Marsh et al., 2007). Yet, an important factor is the fact that the AMOC itself transports high‐salinity water from the subtropical to the subpolar North Atlantic, hence maintaining high‐salinity conditions in the convection regions. This provides a powerful feedback—called the salt‐advection feedback–that has kept the AMOC strong throughout the Holocene. However, models across the full spectrum of complexity have identified the concerning possibility that the AMOC could be prone to collapse. The basic idea is that the salt‐advection feedback that currently maintains a strong AMOC can also work against it: a weakened AMOC would transport less salt into the subpolar North Atlantic, leading to reduced convection and even more weakening of the AMOC. A state would result in which no NADW is formed, and the deep Atlantic is either stagnant or experiences basinwide upwelling of abyssal waters formed around Antarctica. An AMOC collapse would have global consequences and could lead to reduction in surface air temperatures of up to 10 °C in the North Atlantic (Barreiro et al., 2008; Jackson et al., 2015; Liu et al., 2017; Manabe & Stouffer, 1988; Vellinga & Wood, 2002). Evidence of temperature change of this magnitude has been identified in paleo‐proxy records (Blunier & Brook, 2001; de Abreu et al., 2003; Dansgaard et al., 1993), giving credence to the hypothesis that AMOC collapse events were responsible for rapid climate change during the Pleistocene era of ice ages (Broecker et al., 1990). The Fifth Assessment Report of the Intergovernmental Panel on Climate Change identifies an AMOC collapse as one of the tipping points in the climate system (Collins et al., 2013), with a low probability of occurrence but potentially with a high impact."

The IPCC writes in that latest 5th Assessment Report, part 1, chapter 3 on oceans: "The Atlantic Meridional Overturning Circulation (AMOC) consists of an upper limb with net northward transport between the surface and approximately 1200 m depth, and a lower limb of denser, colder, fresher waters returning southward between 1200 m and 5000 m. The AMOC is responsible for most of the meridional transport of heat and carbon by the mid-latitude NH ocean and associated with the production of about half of the global ocean’s deep waters in the northern North Atlantic. Coupled climate models find that a slowdown of the AMOC in the next decades is very likely, though with uncertain magnitude."

Btw, the cooling in that region is not caused by cold meltwater (as someone suggested). Not enough meltwater. But enough to change salinity where it matters.

The observed slowdown is well explained in this paper: January 2018, Caesar et al. Nature 556, 191, "Observed fingerprint of a weakening Atlantic Ocean overturning circulation". That is the one that shows that the pattern of sea surface temperature trends produced by atmosphere-ocean climate models when co2 is doubled in the atmosphere is just like the pattern we actually observe (a pattern that does not arise if co2 is not doubled). Unfortunately, lots of science is behind the paywalls of the journals- not as it should be. The paper says: "The AMOC is one of Earth’s major ocean circulation systems, redistributing heat on our planet and thereby affecting its climate. At the same time, it is a highly nonlinear system with a critical threshold, depending on a delicate balance of temperature and salinity effects on density, and is considered one of the main tipping elements of the Earth system. Changes in Atlantic overturning have been responsible for some of the strongest and most rapid climate shifts during the Quaternary Period (the past 2.6 million years). These historical changes in the AMOC have not only affected the North Atlantic and surrounding landmasses, but have also had global impacts. [...] Given the potentially disruptive impact of a major change in the AMOC, it is imperative to better understand whether and how the AMOC is responding to modern anthropogenic warming." and finds: "Our findings show that in recent years the AMOC appears to have reached a new record low, consistent with the record-low annual SST in the subpolar Atlantic (since observations began in 1880) [...] Although long-term natural variations cannot be ruled out entirely 29,30 , the AMOC decline since the 1950s is very likely to be largely anthropogenic, given that it is a feature predicted by climate models in response to rising CO 2 levels. [...] The AMOC weakening may already have an impact on weather in Europe. Cold weather in the subpolar Atlantic correlates with high summer temperatures over Europe, and the 2015 European heat wave has been linked to the record ‘cold blob’ in the Atlantic that year. Essentially, low subpolar SSTs were found to favour an air-pressure distribution that channels warm air northwards into Europe. Model simulations further suggest that an AMOC weakening could become the “main cause of future west European summer atmospheric circulation changes” , as well as potentially leading to increased storminess in Europe. AMOC weakening has also been connected to above-average sea-level rise at the US east coast and increasing drought in the Sahel. Continued global warming is likely to further weaken the AMOC in the long term, via changes to the hydrological cycle, sea-ice loss and accelerated melting of the Greenland Ice Sheet, causing further freshening of the northern Atlantic.

A balanced assessment by the authors inviting discussion is here: "If you doubt that the AMOC has weakened, read this"
(I am not one of the authors of any of these works I cited.)

Apologies for such a long post - not as it should be - and for having been forced off-topic - did not want to - but this challenge was not trolling, I hope, but asking for references. While we wait for LV to arrive.
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