I’m far, far from home but I’m going to try hard to respond politely to this thread. (Also, if my wife twigs I’m still going on the forum, I’m dead!!!)
I’m turning over a new leaf and trying not to insult.
Firstly. G hall
- it was my impression over the sea level rise from Greenland ice-sheet melting debate long ago that you were displaying extraordinary ‘arrogance’ over the about 7m rise calculated by many other people. I felt that your attitude to them was derisory and you felt that this calculation was flawed. I remember that you then did your own superior calculation but assumed it was 7 Kilometres rise – out by a factor of 1000
Here’s a suggestion, sincerely meant kindly – I will try very hard not to be insulting any more here and furthermore, I hope to go to Norwich / Gt Yarmouth later in the Year so if you are in that region, which I’ve assumed you are, may we could meet and have a drink and laugh all this past rubbish off.
Secondly, Exorcist:-
The calculation of approximate sea level rise is very simple, - ultimately about 10 seconds probably.
Logic:-
Working on your ‘box’ principle, one can assume the existing ocean volume can be represented by a ‘box’.
current ocean volume, V1 = ocean area x current H1,
Assuming the ocean area doesn’t change (see later for discussion), new volume after melted ice V2 = ocean area x new height H2, thus:-
H2=V2/area, and H1=V1/area, so ......... therefore H2-H1 = V2/area – V1/area
which re-arranges to, H2-H1 = (V2-V1)/area
But V2-V1 is simply the melted ice volume, so the calculation reduces simply to
Melted ice volume / ocean area.
Now, in sense you are correct to put in say, a 0.92 correction because the volume of ice is greater than water (below 4 deg),, but you should also consider the resulting water will warm to say a average of what 15 deg C and will expand.
Also, a lot of the Greenland ice is incredibly compressed at the bottom by the weight of it above so it is not ‘normal’ volume ice.
Even the IPCC do not consider expansion of ocean area in their calculations but also they do not consider isostatic rebound of the Greenland land mass. What I’m suggesting therefore is that there are competing volume/area changing factors which may cancel each other out to some extent.
The volume of the Greenland ice cap was measured, I am fairly certain, several years ago to most scientists satisfaction by differential radar scanning.
Finally, using these figures from wiki,
Current ocean area = 361 X10 km2
Volume of ice = 2.85 million KM3, Okay, put your 0.92 correction then = 2622000 km3
So, increase in height = 2,622,000/361,132,000 which = 0.00726 km = 7.26 metres
If I’ve made a mistake in logic or calculation, I’m sorry – it’s not the highest thing on my mind at the moment but if this IS okay, please try the second or third challenges.
I may not respond for sometime.


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) Exorcist used a 0.92 factor for the melting volume of ice to water, presumably at 0 deg C but ignores any water volume increase as it warms to ? what ? 10 deg C world average.Besoeker has already put a convincing calculation od sea area change, which would lessen sea level rise but also nobody has consider isodtatic rebound of the greenland land mass when the ice is gone, or even that of antarctica. When all is said and done, sea level rise from the greenland ice sheet melt is still going to be 'about' 7m. 
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