I thought it was already a known fact that the melting ice caps will NOT cause the oceans to rise? For the same reason that melting ice in a glass of water does not cause the level of the water to rise. In Before the Flood they mention several times that the oceans will rise and it will cause catastrophes but I thought this was already known to be incorrect.
shareIce caps are made of different density than the surrounding salt water. Ice caps are fresh water which has different buoyancy than salt water. It will increase the mass of water as it melts.
Tap water and ice cubes are the same density. As the ice cube melts, only the part under water will increase the mass below it.
Ice caps are on land. Those will rise sea levels.
Sea ice is like the ice cube in a glass and doesn't affect sea levels. Sea ice is more of an indicator. Less sea ice exposes dark water, which absorbs more heat.
Sea ice is also an ecological niche. Krill feeds on plankton underneath the ice and fish feed on krills. Less ice = less plankton = less krill = less fish & chips.
In the Antarctic there is land under the ice. Not in the Arctic.
The ice in the Arctic already increases and decreases over the course of a year due to the seasons. At its largest, the Arctic ice sheet is about twice the size it is at its smallest.
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When it comes to being a role model, "good enough" usually isn't.
There are glacial ice shelves on Greenland melting away and ice in the arctic does rise over the surface, but as we all know, a tip of the iceberg is just that- the tip. However melted ice at higher temps will take up more volume, and is more than "an indicator", because the masses of ice in the poles has been a ballast and stabilizing source to keep temps cooler everywhere else, and the more we lose this natural balance with diminishing ice at the poles, the more the temps elsewhere in our thin atmosphere increase.
Did you NOT watch this film and see the gushing rivers of melted ice draining off of Greenland and into the sea?
Plus earth and vegetation is always washing off the continents and islands as mud and debris and garbage, and into the ocean to settle on the floor and raise the sea level. And so as more floods come from hotter sea storms more flood mud washes off of land. Care must be taken to minimize erosion, and use of garbage for land fill and sea walls. Sand that was on Floridas beaches before the last hurricane has been washed to sea, and then has to be reclainmed by machines using more fossil fuels- a vicious circle.
Finally it is known that sea rise and storm surges happen more in warmer waters at warmer times of the year simply because a liquid takes up more volume when it's warm as opposed to when cooler
I'm not involving myself on either side of the discussion (although I do have my own thoughts on the matter). I was merely responding to Joe_Cinema's statement:
Ice caps are on land.
Ice caps are on land by definition. Arctic sea ice is not an ice cap. Greenland is.
shareFair point. I didn't do my research and made a schoolboy error!
Sorry for my misinformation.
Is Greenland at risk of melting?
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When it comes to being a role model, "good enough" usually isn't.
As a side note. Also is it not true that if the temperature of the sea rises, this causes it to expand also?
shareThat's an interesting point...
Pure water, unlike most liquids, expands when it freezes, so there could be an argument that when the ice caps melt, they contract. However, this may not be true of salt water (I'm simply not knowledgeable in that area). Even if it is the case, there will be a temperature where the water begins to expand as it is heated and gets warmer. But, again, I don't know what that temperature would be.
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When it comes to being a role model, "good enough" usually isn't.
Most things usually contract with cold and expand with heat, and so then the temperature is just a scale.
Despite all the obfuscation- ice is melting off land and going into the sea, and sea ice, which may tower hundreds of feet above sea level- and yet still be just the tip of an iceberg- is melting both above and below the water line.
The accurate satellite data we have since 1980 shows a steady decline with vary little variation from a standard deviancy.
The Antarctic has a piece of ice the size of Connecticut ready to break off and begin floating into the larger ocean.