Global decline in ocean memory over the 21st century | Hacker News Reader

Global decline in ocean memory over the 21st century

science.org

95 pointsgumby18 comments

So more loss of stability. Decreased predictability. Typical for the climate emergency we're in, and typical precursor for a significant state change event in complex systems.

I hadn't heard of the term ocean memory before. For something more specific and slightly related, check out the Atlantic Meridional Overturning Circulation. Another complex system or subsystem that is being affected with potential for significant impact.

> and typical precursor for a significant state change event in complex systems.

We're about to rediscover food chains and the domino effect sprinkled with a heavy dose of "told you so"

Sadly, there is no "told you so". The kind of people who are impervious to reason before they create a catastrophe are equally impervious in its wake. They're either dead, along with all the other people they got killed, or intransigent to the last.

Carlo Cipolla developed the "Basic Laws of Human Stupidity" as a quadrant model, positing Intelligence, Helplessness, Predation and Stupidity as four individual types [1]. Of all dark human qualities, including malicious psychopathy Cipolla thought that "the stupid person is the most dangerous person that exists".

[1] This paper offers an insightful analysis: https://www.scirp.org/journal/PaperInformation.aspx?PaperID=...

OT, your comment was intellectual pleasing, that I read it twice.

Oh man that is a fun read:

> A large class of stupid agents are those who act only “on principle”, thereby frustrating the work of others without gaining any personal benefits, as often occurs in board meetings, on faculty or departmental committees, in political parties, assemblies with unanimous voting regulations, even in international associations of nations when a nation vetoes a proposition “based on principle”.

> the stupid person is the most dangerous person that exists

But everybody is relatively stupid compared against others, if multiple dimensions of intelligence are measured.

Or use an absolute scale, and I think we can round everybody’s intelligence down to zero. Humans are surely not that smart - certainly in my experience.

> But everybody is relatively stupid compared against others, if multiple dimensions of intelligence are measured.

Absolutely true. And, to go further, "intelligence" is almost impossible to measure.

Look more closely at Cipolla's theory though, and you'll see it is not about *measurement".

He doesn't set up a (diametric) scale of intelligent <---> stupid.

It's about behaviour between people who transact. He labels the behaviours (results of transaction) as one of four types.

The one labelled "stupidity" is the lose-lose quadrant, where the parties act in such a way as to destroy value for them both!

So, I guess in theory two rather low IQ people (measured intelligence) could interact in a way that is "intelligent" behaviour.

Does that help explain it in a useful way?

Thanks. The “theory” would perhaps be better served by using clearer, less inflammatory, terms from transactional games like the prisoner’s dilemma, or from evolutionary strategies.

“Intelligence” just mean “cooperate” in a win-win situation (non-zero sum game)?

“1) Intelligent people, 2) Helpless/Naive people, 3) the Bandit and 4) the Stupid person” seem like terrible categorisations to me, because they imply fairly unchangeable attributes. Who wants to live in a world of being labelled? Defecting can be intelligent. Learning how to play tit-for-tat is worthwhile.

Edit: disclaimer: I didn’t read much of the link, because the little I saw triggered my bogus limit. And I hope Cipolla isn’t Spanish - they would get a lot of ribbing.

Conceptually, this is just about that warming a body of water from above tends to result in a thin layer of warm water sitting atop the larger colder body. Anyone who has gone swimming in a temperate lake in summer will experience this; there's a thin warm layer on top. This greatly reduces mixing with the lower body. In winter, such lakes typically 'overturn', i.e. the temperature gradient disappears and the surface water mixes freely with the deep water.

A feature of a shallower warm layer with less deep mixing in the ocean is that it's going to be more susceptible to atmospheric forcing (clouds blocking sunlight, or winds driving surface currents, or a warm wet air mass driving heating). This paper presents modeling runs in support of that hypothesis. Since long-term (months) climate forecasts (El Nino estimates etc) rely heavily on sea surface temperature forecasts (SSTs being fixed data fed into short-term forecasts), this will reduce the accuracy of the long-term forecasts (but not of the short-term forecasts, which are based in part on real-time satellite measurements of SSTs).

One of the more likely long-term effects of this shallower, warmer mixed layer is a reduction in deep-ocean mixing rates, and what that means is less oxygen gets delivered to the deep ocean, so oceanic anoxia and hypoxia events are more likely to become widespread over time. This is a complex situation, however, as nutrient inputs (i.e. fertilizer runoff from intensive agriculture) can cause a massive drawdown of oxygen in the deeper ocean, due to amplification of local biological breakdown of biomass.

https://oceanservice.noaa.gov/podcast/feb18/nop13-hypoxia.ht...

Global oceanic anoxia events have happened in the past, but would really require hundreds-to-thousands of years to develop; what we see now are more regional events linked to the dieoff of large numbers of bottom-dwelling animals. We are definitely headed in that direction under current practices, however:

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

The specific term shouldn’t be “Climate Change” but rather “Climate Chaos” - both accurate and appropriately ominous-sounding.

I've seen "Climate Crisis" a lot more recently, which I think is an apt descriptor. I've also seen "Climate Emergency", but it doesn't alliterate as well.

Climate Crisis is technically incorrect. For some places the climate is, perhaps temporarily, improved with respect to their local goals. Climate Chaos provides the desired omenisity while accurately describing the physics.

I think this needs a lot more scrutiny.

What did we really know about the ocean in 1899, which is when part of the data starts? Are they just using mathematical models of 1899? What's the margin of error for such a case?

The British admiralty has maintained data on ocean currents and temperatures since the mid 19th century. They operated a number of scientific studies (cf Darwin on the Beagle). I'm mildly surprised the time series starts as late as 1870.

Whenever an abstract uses the word "noise" it has one of two meanings:

* An unpredictable component of a signal, due to things that are inherently theoretically unpredictable, such as Johnson–Nyquist noise.

* Part of a signal that the writers do not understand or cannot model due to shortcomings of the model. Describing such signals as 'noise' generally indicates a poor or incomplete paper.

I suspect in this case, it's the latter sadly.

I believe noise here just refers to high frequency variation in atmospheric forcing. The ocean can be thought of as adding inertia to the climate system like a massive flywheel. This means it reacts slowly to change. This paper is arguing the ocean is becoming quicker to respond to changes it sees (or that’s my interpretation after a first read)

This paper is tangentially related https://onlinelibrary.wiley.com/doi/10.1111/j.2153-3490.1976...

Quick clarification: the noise is applied as a perturbation of their model which is meant to tease out its response to high frequency variation in sst. It is not really a limitation of their model but part of its design.

Dither [1]

[1] https://en.wikipedia.org/wiki/Dither

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