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by jsilence 3038 days ago
Your reasoning omits that there is also a large amount of energy stored im the oceans. The greenlandic glaciers have already sped up and are calving into the oceans where there is plenty of energy to melt them.
2 comments

That's the whole point of the study of energy storage over fifty years. The interesting point is that the amount of ice calving off from the Greenland glaciers is minute compared to the amount of ice on Greenland. It doesn't matter how spectacular these calves are and they are spectacular and from our point of view they are huge, you can think of them as flaking skin off an elephant.

The problem I see here is that the energy flows and pathways required are of such a magnitude and are so complex that the simplistic modelling being used basically ignores it.

For every kilotonne of ice being calved, it will require, at a minimum, the energy stored in 4 kilotonnes of sea water at 20 degrees Celcius. The resulting temperature of that sea water would be reduced to just above freezing point of water. If you, say, set the limit at a 1 degree Celsius drop, then we are looking extracting the energy of about 84 - 85 kilotonnes of sea water. You still need to take into account the energy conduction through water and also from water to the ice.

At this end of the globe, we see stories often enough of the end of small icebergs that have calved off the Antarctic ice mass. Many of these have been tracked from the initial calve to their final demise and it takes many years for even small ones to finally disappear.

To get any serious ice melt, you have to have serious amounts of energy flowing into that ice.

One question to ask is how the calving is occurring? There can be a variety of ways this can happen and they are not all caused by temperature increases. This, in itself, is a very interesting subject and there are some quite complex processes involved.

The world around us is extremely complex and we have very little understanding of how things work, irrespective of what is portrayed in popular media.

Historical records do indicate that the Arctic Polar ice mass has been of varying sizes. Some of these have essentially indicated that the ice mass was very small at some points in history and at other times very large. Some of these records and reports go back many hundreds of years.

Once they fall into the sea the displacement occurs. It doesn't matter after that how long they take to melt, all that matters is that they fall off land and into the ocean.

So melting is an issue only for ice that melts on land and then flows into the oceans because that represents new water volume.

It's not that simple. You must take into consideration the amount of ice that is deposited onto the ice mass from snow and condensation of water vapour.

If the rate of deposit is greater than the rate of calving then there is a nett addition to the ice mass. If the rates are equal, then you have steady state. If the rate of calving is greater then you have a nett loss.

This has to be looked at over a longer period of time to see what the variation is in the data.

Of course they don't need to actually melt to affect sea rises, they just have to fall into the ocean.