Atlantic currents seem to have started fading last century | Hacker News Reader

Atlantic currents seem to have started fading last century

arstechnica.com

36 pointspseudolus13 comments

The 2013 NOVA episode "Earth From Space"[1] gives a really good explanation of how these conveyor belt currents work, and has some beautiful computer generated graphics that depict the microcurrents in the oceans that they're able to build because of the data collection from satellites. I re-watch it every couple years, and this story prompted me to start watching it again just now.

[1]: https://www.pbs.org/wgbh/nova/video/earth-from-space/

So global warming will eventually cause an ice age right? That's apropos.

Not exactly. We would normally be about to go into an ice age - sometime in the next few thousand years - and actually nothing about the gulf stream slowing is particularly human derived from that perspective.

Conceivably global warming could stop it, accelerate it, just be a nuisance term. We simply don't know.

We're already in an Ice Age, namely the Quaternary. The glaciers have receded somewhat, but the Earth still has a high level of glaciation compared to other geological periods.

One of the most important factors is the arrangement of the continents[1]. First, having a large polar continent allows ice to accumulate and increase the Earth's albedo significantly. Second, having two major oceans instead of one decreases the efficiency of heat transfer around the globe, allowing other pockets of glaciation to occur. In a scenario with no polar continents and only one major ocean a glaciation is virtually impossible regardless of where we are in the Milankovitch cycles[2], because the Earth is effectively swimming in a thermodynamic bath. Atmospheric composition is actually a relatively minor factor, it's just that human activity can't shift continents around or affect solar cycles and those both change on much longer timescales than human activity.

[1] https://www.wisegeek.com/how-does-the-placement-of-the-conti...

[2] https://en.wikipedia.org/wiki/Milankovitch_cycles

An ice age in Europe, and maybe colder weather on the US east coast. It will probably also have other effects, but it's really hard to predict.

We are in an ice age right now

Interglacial

The movie The Day After Tomorrow is quite good, and revolves around this happening.

It's an absurdly unrealistic depiction of the concept.

Yes especially that scene when you have a couple of hundred americans trying to cross the Mexican border, when in reality it would be millions.

I'm really curious to know how this will pan out, the UK should get warmer because of CO2 but with the current stopping we should be colder.

Seems like the UK might stay the same but be a bit dryer?

Biomes with real estate on the ocean floor are the ones to be complaining, not the UK. The deep ocean is fed by the north atlantic downwelling. When that stops, the water will go anoxic. Most ecosystems in that realm will just end.

There’s an easy rule of thumb for predicting how climate will change: Every possible thing will get worse.

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