Melting sea ice and rising sea levels

Chris S

Guru
Location
Birmingham
Ice floats because it is less dense than water. When it melts its weight stays the same but its volume actualy goes down.

Would melting sea ice actually reduce sea levels?
Is it just the ice currently above sea level that could cause them to rise?
 

GrumpyGregry

Here for rides.
According to NASA melting sea ice will have no effect on global sea levels but will have a whole raft of climatic side effects, few of them beneficial.
 

FishFright

More wheels than sense
Globally Sea ice isnt a problem re global warming, the Antarctic ice field is another matter entirely.
Locally the loss of the Arctic sea ice is a major issue as it's looks like it could pull the North Atlantic Conveyor current much further South and deprive us of the moderating effect on our climate giving us a similar climate as other places at our latitude.
 
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Drago

Guest
The biggest contributor to rising sea levels is thermal expansion of the sea water. Much disagreement about what rise a melted ice cap would cause, but whichever number you fancy comes in well behind simple thermal expansion as the biggest contributor.
 

FishFright

More wheels than sense
The biggest contributor to rising sea levels is thermal expansion of the sea water. Much disagreement about what rise a melted ice cap would cause, but whichever number you fancy comes in well behind simple thermal expansion as the biggest contributor.

Got a link for this ? I'm Interest in reading about it, not a criticism
 

slowmotion

Quite dreadful
Location
lost somewhere
Got a link for this ? I'm Interest in reading about it, not a criticism
Try this....
https://www.ipcc.ch/ipccreports/tar/wg1/411.htm
 

swansonj

Guru
Ice floats because it is less dense than water. When it melts its weight stays the same but its volume actualy goes down.

Would melting sea ice actually reduce sea levels?
Is it just the ice currently above sea level that could cause them to rise?
Floating ice displaces a volume of water equal to its weight (Mr Archimedes said so). As floating ice melts, the weight doesn't change, so the volume of water displaced doesn't change, so the sea level doesn't change. You are correct that, as it melts, ice takes less volume, but what happens is that the bit of the ice that was above the surface contracts into the volume that was previously below the surface.

That is simply an answer to the physics of your question about floating ice and in no way contradicts or invalidates the points others have made about (a) other consequences of melting sea ice and (b) the consequences of ice melting that wasn't floating to start with.
 

Wobblers

Euthermic
Location
Minkowski Space
Globally Sea ice isnt a problem re global warming, the Antarctic ice field is another matter entirely.
Locally the loss of the Arctic sea ice is a major issue as it's looks like it could pull the North Atlantic Conveyor current much further South and deprive us of the moderating effect on our climate giving us a similar climate as other places at our latitude.

The loss of sea ice is actually a problem for global warming, as ice reflects more of the sun's heat than the seawater that replaces it. This is a major effect of sea ice loss.

The North Atlantic Conveyor is driven by deep water formation, where cold, dense water sinks to the bottom of the Atlantic. It's affected by the influx of fresh water which inhibits the process - that's not just from melting sea ice but a larger contribution comes from melting permafrost in Siberia.

Deep water formation, and the Gulf strream that it drives, have shut down before, quite often: they can be seen in the paleoclimate records. The effect is profound. The last time it happened (11 000 years ago, the Younger Dryas), the whole of the northern hemisphere reverted to periglacial conditions. The UK which had been temperate grasslands became tundra in the space of a few decades. It's probably something that we want to avoid!
 
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FishFright

More wheels than sense
Google is amazing .. The things you can find to paste on a forum..
So how much tax do we need to pay to fix the big warm up?

Tax won't sort it out. It's up to every single one us using a LOT less energy.

Forex ;

Central heating - how many us heat empty rooms ?
Car journeys - pretty obvious really
Air con in your cars - Amazing how so many people seen to 'need' it on constantly
Buying more locally grown meat and veg - do you really need that lettuce from Kenya ?
Buy less crap made on the other side of the world - Basically its the drive for us to consume constantly which dives the lot


But what about me and my lifestyle ? Tough !
 
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