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The issue is the Arctic is not likely to re-freeze even with Gulf Stream gone. This is a little bit like bi-stable switch. Once it switches one way it wants to

The issue is the Arctic is not likely to re-freeze even with Gulf Stream gone. This is a little bit like bi-stable switch. Once it switches one way it wants to be in that position until there is enough force to push it the other way.

Kaibeezy 5y ago
I see what you’re saying. The Gulf Stream affects ocean water distribution worldwide, but doesn’t necessarily have much affect on the Arctic Ocean itself.
- lmilcin 5y ago
  Of course it makes it a little warmer, but the point is, the most important factor that makes Arctic Ocean... well... arctic... is whether it reflects sunlight or not. Water is dark and accepts a lot of sun's energy, getting warmer. With ice present it reflects a lot of that energy back to space. The amount of energy difference we are talking about is astounding. The Gulf Stream, as large as it is, pales in comparison to the amount of sunlight reflected by patch of snow the size of entire Arctic Ocean. Now, I don't want to say Gulf Stream is insignificant. It will definitely have huge effect, especially on Europe where I live. The most important effect, per my understanding, is less rainfall. Because that warm water vaporizes and those vapors tend to turn to rain/snow over Europe. Shift in wind patterns I don't understand so can't elaborate.
  - chrisco255 5y ago
    If the water goes below freezing temperatures, it will tend to freeze and turn white. If the hot tropics are currently pulling warm water up towards the Arctic via the AMOC, the average water temperature of the Arctic is increased. If that pattern were to decrease, you would get colder Arctic water that tends to freeze more easily. A lot of ocean water is already covered by something else with albedo: clouds. Particularly in the poles, clouds tend to form very easily. Reduced AMOC circulation is associated with dramatic effects in the past for Earth's climate. "The Little Ice Age was one of the coldest periods of the last ~10,000 years in the Northern-Hemisphere. Although there is increasing evidence that this cooling was associated with a weakening of the Atlantic Meridional Overturning Circulation (AMOC), the sequence of events that led to a significant reduction in deep convection has yet to be explained." https://instaar.colorado.edu/meetings/AW2021//abstract_details.php?abstract_id=53 https://instaar.colorado.edu/meetings/AW2021//abstract_detai...
    - lmilcin 5y ago
      > A lot of ocean water is already covered by something else with albedo: clouds. Particularly in the poles, clouds tend to form very easily. You are wrong. Antarctica is the driest place on Earth. https://www.google.com/search?q=driest+continent+on+earth https://www.google.com/search?q=driest+continent+on+earth "Antarctica is the driest continent; it is almost entirely desert. Very little snow or rain falls on the continent (...)" Dry == not much cloud cover. And if there are ice crystals in atmosphere it mostly shows as haze, it is not effective at reflecting large portion of the sunlight. Clouds form from moisture from evaporating water. This usually requires warm water to be significant. In northern hemisphere this warm water is supplied by Gulf Stream. Also, as a side note, clouds are not nearly as effective at reflecting energy back to space as snow is. First, ice is there all the time, every day. Clouds are rarely continuous for long periods. Second, clouds are scattering light. Of which some goes back to space. Snow is reflecting it. I know on picture they both look white because humans are poor at discerning levels of whiteness. https://en.wikipedia.org/wiki/Cloud_albedo https://en.wikipedia.org/wiki/Cloud_albedo "Cloud albedo on a planet varies from less than 10% to more than 90% and depends on drop sizes, liquid water or ice content, thickness of the cloud, solar zenith angle, etc Clean snow has albedo of 90%, which is the best clouds can get in optimal conditions, but rarely actually get there. And difference between 90% and 80% of albedo is TWICE the amount of energy absorbed. Without it there is not going to be a lot of clouds and rain in northern Canada or Europe. And arctic is already quite dry.
      - chrisco255 5y ago
        Of course, my comment was on cloud cover above water, near the poles, including the water surrounding Antarctica, which has frequent snowfall including as we speak. Take a look at current satellite imagery of the area surrounding Antarctica: https://www.windy.com/-Satellite-satellite?satellite,-63.744,44.517,4 https://www.windy.com/-Satellite-satellite?satellite,-63.744... Cloud cover is more common over ocean water than on land. Also, Antarctica's cloud cover is larger in the winter than in the summer: "The seasonal cycle of cloud cover is found to range from 45%–50% during the short summer to a relatively constant 55%–65% during the winter. " https://journals.ametsoc.org/configurable/content/journals$002fclim$002f20$002f3$002fjcli4005.1.xml?t:ac=journals%24002fclim%24002f20%24002f3%24002fjcli4005.1.xml https://journals.ametsoc.org/configurable/content/journals$0... You can find similar studies on the cloud cover above exposed water in the Arctic. It doesn't matter how variable clouds are, what matters is an average over a long period of time. Clouds have a far more dramatic effect on global temperatures, because they have the ability to reflect absorption of solar energy in the hottest parts of the planet (the tropics), where ice cannot exist. They can and do form over most of the ocean water which covers 2/3 of the planet's surface. Average cloud cover over ocean water is 90%! Some clouds scatter light. Some are extremely effective at reflecting light into space. Depends on zenith angle of the light (based on latitude), the altitude of the cloud, water content and shape and thickness overall. https://www.researchgate.net/publication/334183298_High_cloud_coverage_over_melted_areas_dominates_the_impact_of_clouds_on_the_albedo_feedback_in_the_Arctic https://www.researchgate.net/publication/334183298_High_clou...

Kaibeezy 5y ago

I see what you’re saying. The Gulf Stream affects ocean water distribution worldwide, but doesn’t necessarily have much affect on the Arctic Ocean itself.

lmilcin 5y ago
Of course it makes it a little warmer, but the point is, the most important factor that makes Arctic Ocean... well... arctic... is whether it reflects sunlight or not. Water is dark and accepts a lot of sun's energy, getting warmer. With ice present it reflects a lot of that energy back to space. The amount of energy difference we are talking about is astounding. The Gulf Stream, as large as it is, pales in comparison to the amount of sunlight reflected by patch of snow the size of entire Arctic Ocean. Now, I don't want to say Gulf Stream is insignificant. It will definitely have huge effect, especially on Europe where I live. The most important effect, per my understanding, is less rainfall. Because that warm water vaporizes and those vapors tend to turn to rain/snow over Europe. Shift in wind patterns I don't understand so can't elaborate.
- chrisco255 5y ago
  If the water goes below freezing temperatures, it will tend to freeze and turn white. If the hot tropics are currently pulling warm water up towards the Arctic via the AMOC, the average water temperature of the Arctic is increased. If that pattern were to decrease, you would get colder Arctic water that tends to freeze more easily. A lot of ocean water is already covered by something else with albedo: clouds. Particularly in the poles, clouds tend to form very easily. Reduced AMOC circulation is associated with dramatic effects in the past for Earth's climate. "The Little Ice Age was one of the coldest periods of the last ~10,000 years in the Northern-Hemisphere. Although there is increasing evidence that this cooling was associated with a weakening of the Atlantic Meridional Overturning Circulation (AMOC), the sequence of events that led to a significant reduction in deep convection has yet to be explained." https://instaar.colorado.edu/meetings/AW2021//abstract_details.php?abstract_id=53 https://instaar.colorado.edu/meetings/AW2021//abstract_detai...
  - lmilcin 5y ago
    > A lot of ocean water is already covered by something else with albedo: clouds. Particularly in the poles, clouds tend to form very easily. You are wrong. Antarctica is the driest place on Earth. https://www.google.com/search?q=driest+continent+on+earth https://www.google.com/search?q=driest+continent+on+earth "Antarctica is the driest continent; it is almost entirely desert. Very little snow or rain falls on the continent (...)" Dry == not much cloud cover. And if there are ice crystals in atmosphere it mostly shows as haze, it is not effective at reflecting large portion of the sunlight. Clouds form from moisture from evaporating water. This usually requires warm water to be significant. In northern hemisphere this warm water is supplied by Gulf Stream. Also, as a side note, clouds are not nearly as effective at reflecting energy back to space as snow is. First, ice is there all the time, every day. Clouds are rarely continuous for long periods. Second, clouds are scattering light. Of which some goes back to space. Snow is reflecting it. I know on picture they both look white because humans are poor at discerning levels of whiteness. https://en.wikipedia.org/wiki/Cloud_albedo https://en.wikipedia.org/wiki/Cloud_albedo "Cloud albedo on a planet varies from less than 10% to more than 90% and depends on drop sizes, liquid water or ice content, thickness of the cloud, solar zenith angle, etc Clean snow has albedo of 90%, which is the best clouds can get in optimal conditions, but rarely actually get there. And difference between 90% and 80% of albedo is TWICE the amount of energy absorbed. Without it there is not going to be a lot of clouds and rain in northern Canada or Europe. And arctic is already quite dry.
    - chrisco255 5y ago
      Of course, my comment was on cloud cover above water, near the poles, including the water surrounding Antarctica, which has frequent snowfall including as we speak. Take a look at current satellite imagery of the area surrounding Antarctica: https://www.windy.com/-Satellite-satellite?satellite,-63.744,44.517,4 https://www.windy.com/-Satellite-satellite?satellite,-63.744... Cloud cover is more common over ocean water than on land. Also, Antarctica's cloud cover is larger in the winter than in the summer: "The seasonal cycle of cloud cover is found to range from 45%–50% during the short summer to a relatively constant 55%–65% during the winter. " https://journals.ametsoc.org/configurable/content/journals$002fclim$002f20$002f3$002fjcli4005.1.xml?t:ac=journals%24002fclim%24002f20%24002f3%24002fjcli4005.1.xml https://journals.ametsoc.org/configurable/content/journals$0... You can find similar studies on the cloud cover above exposed water in the Arctic. It doesn't matter how variable clouds are, what matters is an average over a long period of time. Clouds have a far more dramatic effect on global temperatures, because they have the ability to reflect absorption of solar energy in the hottest parts of the planet (the tropics), where ice cannot exist. They can and do form over most of the ocean water which covers 2/3 of the planet's surface. Average cloud cover over ocean water is 90%! Some clouds scatter light. Some are extremely effective at reflecting light into space. Depends on zenith angle of the light (based on latitude), the altitude of the cloud, water content and shape and thickness overall. https://www.researchgate.net/publication/334183298_High_cloud_coverage_over_melted_areas_dominates_the_impact_of_clouds_on_the_albedo_feedback_in_the_Arctic https://www.researchgate.net/publication/334183298_High_clou...