6 ms·

What would happen if the Gulf Stream did collapse? Would a different similar circulatory system emerge soon after? Would the lack of a dominant system lead to

by cwkoss 5y ago

What would happen if the Gulf Stream did collapse? Would a different similar circulatory system emerge soon after? Would the lack of a dominant system lead to many more smaller chaotic systems? Do we just not know what would happen, so that it's concerning in that it's unknowable?

the8472 5y ago
There is no requirement that water MUST circulate. It could simply stagnate. That's pretty much the worst case though, a weakened gulf stream is not the same as a total collapse.
- chrisco255 5y ago
  As long as there are temperature differences between the poles and the equator, there will be movement of water. That's thermodynamics in play.
- colinmhayes 5y ago
  I think that would require all the water be the same temperature.
cinntaile 5y ago
Just watch The Day After Tomorrow to know what happens.
- jacquesm 5y ago
  No, that is heavily sensationalized. But a new 'small ice age' as a result of the gulfstream shutting down is a serious possibility, even if it changed direction that would already cause serious problems for very large parts of Europe.
  - fosk 5y ago
    Although the benefit would be increased reflection of sunlight due to more icy (reflective) surface which would alleviate (or reverse?) the current weather warming trend.
  - geocrasher 5y ago
    Sensationalized? Sure. Hollywood. But incorrect? It's hard to know.
    - jacquesm 5y ago
      The basic premise is faulty, a chance in the ocean currents would not immediately cause massive climate change, it would take a couple of centuries but would be pretty much inevitable. It likely would also accelerate other processes already in motion, so more extreme weather would be a pretty safe bet but not to the degree depicted in the movie.
    - jbay808 5y ago
      Well, they forgot to account for adiabatic heating of that cold air getting pulled out of the upper atmosphere, which would have made it quite hot when it hit the ground. If I recall, that cold air was the central threat in the movie.
      - rjldev 5y ago
        We actually ran the numbers on that as an exercise during my undergrad degree (meteorology), iirc it would end up the same as the surface air temperature
  - cinntaile 5y ago
    I guess the joke flew over your head :P
    - jacquesm 5y ago
      I guess you're on the wrong website.
      - cinntaile 5y ago
        No worries, I don't usually joke much on HN. Sometimes jokes work here, maybe climate change is a bit too polarized.
        jacquesm 5y ago
        Or maybe it is just a bit too serious.
- Shorel 5y ago
  Films like that, showing immediate and extreme change over a couple of hours instead of the gradual over-decades change that is more likely to happen, are part of the problem. People remember the film, and see nothing similar happening, and claim nothing is actually happening. All this while the change is going steady.
jacquesm 5y ago
You can kiss Northern Europe as a habitable area goodbye. So yes, it matters quite a bit.
- failuser 5y ago
  Northwest Russia is habitable. Not that pleasant, but habitable.
  - jacquesm 5y ago
    For a relatively limited number of people and with a standard of life that doesn't compare to western/northern Europe. It will be 'a bit of an adjustment' to put it euphemistically. I've lived in Northern Canada, which is somewhat comparable to Northwest Russia and sure, it's doable, but civilization as it currently exists in the countries that are exposed to this will cease, the present day number of inhabitants will be unsupportable. Just trying to imagine the UK with a climate shift like that and the mind boggles. What works for Iceland will not work for the UK without a massive reorientation, which is probably a friendly way of writing 'mass die-off'.
    - myth_drannon 5y ago
      Novosibirsk, Russia is 1m+ city... with some effort you can live. Russians are obsessed about populating their country all over even in the most inhospitable places vs Canadians who are just fine with living south of 60th parallel.
      - jacquesm 5y ago
        Go ask them how many of them would like to move family and all to Paris or Amsterdam and how many people from Paris or Amsterdam would like to move to Novosibirsk. I've lived in Northern Canada. Snow isn't nearly as much fun as it is cracked up to be when there is 6+ months of it in some years (I recall one year where the snowplow went on the tractor in October and we had the last snow in June). Those areas are well outside the ones where humans feel comfortable most of the time and don't underestimate the energy budget on a per-person basis required to make those places habitable to begin with.
roter 5y ago
There will always be a Gulf Stream as long as there are westerlies, a coastline, and Coriolis [0] [0] https://rwu.pressbooks.pub/webboceanography/chapter/9-4-western-intensification/ https://rwu.pressbooks.pub/webboceanography/chapter/9-4-west...

by cwkoss 5y ago

the8472 5y ago

There is no requirement that water MUST circulate. It could simply stagnate. That's pretty much the worst case though, a weakened gulf stream is not the same as a total collapse.

chrisco255 5y ago
As long as there are temperature differences between the poles and the equator, there will be movement of water. That's thermodynamics in play.
colinmhayes 5y ago
I think that would require all the water be the same temperature.

cinntaile 5y ago

Just watch The Day After Tomorrow to know what happens.

jacquesm 5y ago
No, that is heavily sensationalized. But a new 'small ice age' as a result of the gulfstream shutting down is a serious possibility, even if it changed direction that would already cause serious problems for very large parts of Europe.
- fosk 5y ago
  Although the benefit would be increased reflection of sunlight due to more icy (reflective) surface which would alleviate (or reverse?) the current weather warming trend.
- geocrasher 5y ago
  Sensationalized? Sure. Hollywood. But incorrect? It's hard to know.
  - jacquesm 5y ago
    The basic premise is faulty, a chance in the ocean currents would not immediately cause massive climate change, it would take a couple of centuries but would be pretty much inevitable. It likely would also accelerate other processes already in motion, so more extreme weather would be a pretty safe bet but not to the degree depicted in the movie.
  - jbay808 5y ago
    Well, they forgot to account for adiabatic heating of that cold air getting pulled out of the upper atmosphere, which would have made it quite hot when it hit the ground. If I recall, that cold air was the central threat in the movie.
    - rjldev 5y ago
      We actually ran the numbers on that as an exercise during my undergrad degree (meteorology), iirc it would end up the same as the surface air temperature
- cinntaile 5y ago
  I guess the joke flew over your head :P
  - jacquesm 5y ago
    I guess you're on the wrong website.
    - cinntaile 5y ago
      No worries, I don't usually joke much on HN. Sometimes jokes work here, maybe climate change is a bit too polarized.
      - jacquesm 5y ago
        Or maybe it is just a bit too serious.
Shorel 5y ago
Films like that, showing immediate and extreme change over a couple of hours instead of the gradual over-decades change that is more likely to happen, are part of the problem. People remember the film, and see nothing similar happening, and claim nothing is actually happening. All this while the change is going steady.

jacquesm 5y ago

You can kiss Northern Europe as a habitable area goodbye. So yes, it matters quite a bit.

failuser 5y ago
Northwest Russia is habitable. Not that pleasant, but habitable.
- jacquesm 5y ago
  For a relatively limited number of people and with a standard of life that doesn't compare to western/northern Europe. It will be 'a bit of an adjustment' to put it euphemistically. I've lived in Northern Canada, which is somewhat comparable to Northwest Russia and sure, it's doable, but civilization as it currently exists in the countries that are exposed to this will cease, the present day number of inhabitants will be unsupportable. Just trying to imagine the UK with a climate shift like that and the mind boggles. What works for Iceland will not work for the UK without a massive reorientation, which is probably a friendly way of writing 'mass die-off'.
  - myth_drannon 5y ago
    Novosibirsk, Russia is 1m+ city... with some effort you can live. Russians are obsessed about populating their country all over even in the most inhospitable places vs Canadians who are just fine with living south of 60th parallel.
    - jacquesm 5y ago
      Go ask them how many of them would like to move family and all to Paris or Amsterdam and how many people from Paris or Amsterdam would like to move to Novosibirsk. I've lived in Northern Canada. Snow isn't nearly as much fun as it is cracked up to be when there is 6+ months of it in some years (I recall one year where the snowplow went on the tractor in October and we had the last snow in June). Those areas are well outside the ones where humans feel comfortable most of the time and don't underestimate the energy budget on a per-person basis required to make those places habitable to begin with.

roter 5y ago

There will always be a Gulf Stream as long as there are westerlies, a coastline, and Coriolis [0] [0] https://rwu.pressbooks.pub/webboceanography/chapter/9-4-western-intensification/ https://rwu.pressbooks.pub/webboceanography/chapter/9-4-west...