[OceanKing]

From the link:

> "While we can definitively say this weakening is happening, we are unable to say to what extent it is related to climate change or whether it is a natural variation," [the first co-author] Piecuch said. "We can see similar weakening indicated in climate models, but for this paper we were not able to put together the observational evidence that would really allow us to pinpoint the cause of the observed decline."

but also...

> [The second co-author] Beal added, "The Gulf Stream is a vital artery of the ocean's circulation, and so the ramifications of its weakening are global. I used to think of the ocean as our last remaining frontier, wild, pristine, and indomitable. It saddens me to acknowledge, from our study and so many others, and from recent record-breaking headlines, that even the remotest parts of the ocean are now in the grip of our addiction to fossil fuels." (emphasis mine)

Seems a little disingenuous to state in the publication that you cannot conclude the cause of the decline, and then in the press release go about definitively blaming it on fossil fuels, including stating that this conclusion is supported by your study.

[perrygeo]

You're under-emphasizing the "and so many others" part. The causes of ocean circulation change are well known. This paper didn't even address the causality part and only focused on confirming the change. But the causality has been studied elsewhere: we know temperature and salinity are two of the drivers, and those are directly influenced by anthropogenic climate change.

So it's more accurate to say that the synthesis of all recent research indicates fossil fuel emissions are a causal factor. The statement could have been worded more clearly, but it's supported by the scientific evidence.

[pierat]

You know, we're supposed to assume sincerity and general good intent to folks here...

But you know, you have to wonder just how many big business astroturfers there are here. We know the oil companies knew about climate change in the 70s, and buried it. It's not at all unbelievable that they would pay influencers and the like to peddle downplays of climate devastation, in order to slow responses.

Obviously, we don't know for sure, since accts here are semi-anonymous. But it would make a great deal of sense to sow confusion and condemnation and downplay the anthropocene.

[avgcorrection]

I think HN is too liberal (in American terms) to focus the Denial Astroturf on. That plays better with more conservative segments. Liberal audiences are fed the Consumer Awareness Cope: drive less and grow your own tomatos on your veranda. Corporations don't cause climate change because consumers need to buy stuff from corporations for them to survive.

And since this is a wealthy and techy audience you can dial up the upper-middle class fantasies of just buying an EV, installing solar on your roofs, and getting Tesla batteries for your own home.

Go a little further still and you reach the Geoengineering Cope... which also fits here...

[growingkittens]

HN is superficially liberal (in American terms), as a side effect of being a technology community: technology causes progress. I have lived in the American South my entire life, and see that HN has a strong, conservative undercurrent.

[DiggyJohnson]

I genuinely think there are very few. Nearly every time I see someone concerned about astroturfing it seems more likely that it’s simply surprise that another individual has a different perspective than your own.

[chimpanzee]

>> We can see similar weakening indicated in climate models

>> we were not able to put together the observational evidence that would really allow us to pinpoint the cause of the observed decline

>> the grip of our addiction to fossil fuels

I take the above to mean that the ocean’s current state cannot be proven to be caused by climate change. But climate change models do indicate a similar effect would be had. So, given the current state, any future effect of climate change would only make things worse.

Importantly, “in the grip of” only implies a future determined by “the hand that grips” not that the past or present was necessarily produced by the same hand.

[aCoreyJ]

The thing is it's impossible to prove any single event or change is caused by climate change because we have no way of showing what would be happening if humans hadn't altered the planet.

With weather we can show that severe events have become more common.

I'd have to read the study thoroughly to know for sure but it seems they can show certain effects of the fossil fuels industry but not actual causation of the overall slowdown, which may be impossible to prove.

[kergonath]

“Prove” has different meanings for most people compared to scientists. As you say, it is impossible to prove that something like this, which results from a complex set of conditions and most likely a complex set of causes, results from a single thing. So we speak in probabilities, confidence intervals, and significance. That’s just science speak.

This results from human-made global warming in the same way as a smoker’s lung cancer results from smoking. The conclusion is also the same in both cases: “don’t do it”. Nobody can prove that it will kill, but it drastically increases the odds.

Also, note that this is not at all unexpected. I remember articles in scientific vulgarisation magazines in the 1990s discussion this and the fact that, counter-intuitively, global warming could result in local cooling in Western Europe because of a weakened Gulf Stream. We are still far from that.

[Smoosh]

> local cooling in Western Europe

This would be bad, but now has me wondering, what would happen to all that energy if it doesn't travel up towards the north pole to be cooled? Could we have an extra hot Central Atlantic, Gulf of Mexico and Caribbean?

Does anyone know of any studies which have looked into this?

[myshpa]

https://www.oecd-ilibrary.org/environment/climate-tipping-po...

[dang]

Single-purpose accounts aren't allowed on HN; nor is using the site primarily for ideological battle. I know these issues are important and your commitment to them is sincere, but we're trying to have a particular kind of conversation here, and this is not a platform suitable for pre-existing agendas.

Since we asked you to stop (https://news.ycombinator.com/item?id=37384170) and you've not only ignored that request but persisted in doing exactly what we asked you not to, I've banned the account.

https://news.ycombinator.com/newsguidelines.html

[myshpa]

> global warming could result in local cooling in Western Europe because of a weakened Gulf Stream. We are still far from that.

https://en.wikipedia.org/wiki/Atlantic_meridional_overturnin...

In July 2023, a paper from a pair of University of Copenhagen researchers suggested that AMOC collapse would most likely happen around 2057, with the 95% confidence range between 2025 - 2095.

It may be a controversial paper, but all probabilities are off after this year. So there is a possibility that it could collapse as soon as two years from now.

[jncfhnb]

Everything is impossible to prove. However fossil fuels are demonstrably casual factors in mechanics that generate the exact effects we see. Effects which correlate extremely well with the timing of our emissions and we’re largely unchanged on such time scales previously.

[hedora]

It’s well understood that increased average global temperature will shut down the gulf stream.

The question is which of a few different climate change model scenarios we’re in, and which of their tipping points we just crossed, not whether climate change drove the weakening of the Gulf Stream.