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Old 28-04-2018, 07:33   #736
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Re: Northwest Passage - 2018

Melting sea ice makes no difference to sea level, it is the continental ice that will dump its load into the sea and raise the levels... but really more importantly to the Earth's climate and less well described here is what will be happening to ocean currents, surface and deep, as the heat is distributed differently around the planet.
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Old 28-04-2018, 08:10   #737
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Re: Northwest Passage - 2018

Quote:
Originally Posted by SailOar
As a thought experiment, if all the Arctic sea ice were to melt (and nothing else changed), would the sea level rise, stay the same, or fall?
The vote now stands at:
Sea Level Rise: 1
Sea Level Same: 2
Sea Level Fall: 0

Although a clear majority favor Sea Level Same, there still is time to vote and sway the outcome.
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Old 28-04-2018, 09:00   #738
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Re: Northwest Passage - 2018

Quote:
Originally Posted by SailOar View Post
As a thought experiment, if all the Arctic sea ice were to melt (and nothing else changed), would the sea level rise, stay the same, or fall?
Stay the same. Although thermal expansion will result in a increase in sea level.
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Old 28-04-2018, 09:12   #739
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Re: Northwest Passage - 2018

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Originally Posted by Exile View Post

Btw, how does one know if the results of a published scientific study have been peer-reviewed? And where would one find the critiques accompanying such a review, whether positive or negative?
This paper is a good example of a peer-review process. The submission and revision, acceptance and publication dates are shown as are the comments of a very public peer-review and interactive discussion ( in which I took part).

https://www.atmos-chem-phys.net/16/3...3761-2016.html
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Old 28-04-2018, 09:16   #740
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Re: Northwest Passage - 2018

Quote:
Originally Posted by jackdale View Post
Stay the same. Although thermal expansion will result in a increase in sea level.
https://www.newscientist.com/article...ea-level-rise/
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Old 28-04-2018, 09:17   #741
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Re: Northwest Passage - 2018

Quote:
Originally Posted by SailOar View Post
As a thought experiment, if all the Arctic sea ice were to melt (and nothing else changed), would the sea level rise, stay the same, or fall?
https://www.newscientist.com/article...ea-level-rise/
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Old 28-04-2018, 10:02   #742
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Re: Northwest Passage - 2018

Quote:
Originally Posted by SailOar
As a thought experiment, if all the Arctic sea ice were to melt (and nothing else changed), would the sea level rise, stay the same, or fall?
We've got another vote for Sea Level Same, but Newhaul is stubbornly digging in his heels and dragging science into the discussion. What say the rest of you?

Sea Level Rise: 1
Sea Level Same: 3
Sea Level Fall: 0
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Old 28-04-2018, 10:30   #743
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Re: Northwest Passage - 2018

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Originally Posted by newhaul View Post
On the other hand

Quote:
The Arctic has a lot of sea ice, too—at least 6.5 million square kilometers—and it is about two meters thick on average, according to the National Snow and Ice Data Center. Dutton and Rignot say that although the sea ice is shrinking, it does not add to water levels as it melts because it is already part of the ocean’s mass. “You can freeze and melt the sea ice as much as you want—it’s not going to change the sea level,” Rignot says. “You’re just changing the state of the water.” Dutton provides an analogy: “If you’re sitting in a bar with a drink with ice cubes, and your cup is full and the ice cubes melt, it’s not going to overflow. That ice is already floating in the water, so it has displaced the volume of its own space.”

But thawing sea ice still plays a role in sea level rise. “The sea ice acts as a blanket on top of the ocean,” protecting the water from incoming solar energy and atmospheric heat, Rignot says. As that frozen coating disappears, its white surface is no longer there to reflect sunlight back into the atmosphere—so the ocean absorbs much more solar energy. “It’s like going from receiving no heat from the sun to receiving the sun’s full heat,” he explains. “It’s a tremendous difference.” This effect accelerates overall warming, which in turn melts more land ice and drives up sea levels. So even though all that melting sea ice may not seem like a big deal because it is not directly adding to sea levels, Rignot says “it matters greatly—the disappearance of that blanket disturbs the whole Arctic system.”
https://www.scientificamerican.com/a...ng-arctic-ice/
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Old 28-04-2018, 11:10   #744
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Re: Northwest Passage - 2018

Quote:
Originally Posted by SailOar View Post
As a thought experiment, if all the Arctic sea ice were to melt (and nothing else changed), would the sea level rise, stay the same, or fall?
Quote:
Originally Posted by jackdale View Post
not quite jack it is a specific gravity thing also have to figure in the fresh water potential of the snowfall based ice contributions
One more thing jack is that sea ice is frozen some of the salts are pushed out of the solution thereby lowering the salt content of the ice and increasing the relative salinity of the surrounding free water.
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Old 28-04-2018, 11:14   #745
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Re: Northwest Passage - 2018

Quote:
Originally Posted by jackdale View Post
Stay the same. Although thermal expansion will result in a increase in sea level.
Jack the possibility of thermal expansion is outside of the given parameters of this hypothetical exercise.
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Old 28-04-2018, 11:18   #746
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Re: Northwest Passage - 2018

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Originally Posted by newhaul View Post
One more thing jack is that sea ice is frozen some of the salts are pushed out of the solution thereby lowering the salt content of the ice and increasing the relative salinity of the surrounding free water.
If it increases the relative salinity of the surrounding water, that water will require more heat loss to freeze. Actually the increased salinity causes the water to sink.
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Old 28-04-2018, 11:19   #747
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Re: Northwest Passage - 2018

Quote:
Originally Posted by newhaul View Post
Jack the possibility of thermal expansion is outside of the given parameters of this hypothetical exercise.
Hence the "although".
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Old 28-04-2018, 11:21   #748
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Re: Northwest Passage - 2018

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not quite jack it is a specific gravity thing also have to figure in the fresh water potential of the snowfall based ice contributions
The weight of the snow would cause the ice to sink a bit more (Archimedes' principle).

As well the snow is a really good insulator, thereby trapping more heat in the water.
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Old 29-04-2018, 05:04   #749
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Re: Northwest Passage - 2018

Quote:
Originally Posted by SailOar
As a thought experiment, if all the Arctic sea ice were to melt (and nothing else changed), would the sea level rise, stay the same, or fall?
VOTE TOTALS
Sea Level Rise: 1
Sea Level Same: 3
Sea Level Fall: 0

Currently voter turnout is light, and there is no waiting in line to vote. Shall we keep the polls open for a few more hours to allow everyone to express their preference? We can call this "science by ballot".
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Old 29-04-2018, 05:29   #750
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Re: Northwest Passage - 2018

Quote:
Originally Posted by SailOar View Post
VOTE TOTALS
Sea Level Rise: 1
Sea Level Same: 3
Sea Level Fall: 0

Currently voter turnout is light, and there is no waiting in line to vote. Shall we keep the polls open for a few more hours to allow everyone to express their preference? We can call this "science by ballot".
Based on what Newhaul & Jack posted along with the science they linked us to, it looks like every vote is arguably correct, with Newhaul's having the slight edge. Why am I not surprised there isn't a more definitive answer?
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