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Sorry forgot Europeans use comas instead of periods for decimal places.
(...)Climate change is happening, as it has always happened, and man has very little to do with it. (...)
Dr. Johnathan Banper(?) sated on the Naked Scientists that Greenland contains enough ice to raise sea level by 7 meters. I did some math. I might be wrong, I'll provide the stats so you can check my calculations.World wide the Earth's oceans have 3.352581414 square meters of area. So to raise sea level by 7 meters you will need AT LEAST 2.3468061515 cubic meters of water. This number is a bit low because quite a bit of land area is less than 7 meters above sea level. The ocean's area will increase by the number of square meters that are less than 7 meters above sea level.Greenland has 2.1660861212 square meters of area. It's ice would need to be AT LEAST 1109 kilometers thick (when melted) to have this much water. Remember that water expands when frozen so the would be the depth of a tank the size of Greenland when filled with all of Greenland's melted ice.If this is right then, in the wonderful parlance of Briton's parliament, "the right honorable Doctor" is full of Bull- sorry male bovine fecal matter.
...and allowing for the other factors that graham.d mentions above means that the given answer seems about right.
So how much will the ocean rise if Antartica melts as well?
Let's get the maths right chaps. 1. The area of the world's oceans is about 335,000,000 sq km2. The area of Greenland (80% covered with ice) is 2,180,000 sq km3. The ice thickness is 2 to 3 km thick but, of course, varies. The estimated total volume of ice is 2,850,000 cubic km.The ocean level rise is therefore:2,850,000/335,000,000 = .0085km = 8.5mAllowing for the lower density of ice (about 0.92 that of water) the result can be corrected to about 7.8m.If you also assume that the ocean level rise will find its way into all the seas on the earth then this number further reduces by a factor 335/361 to give 7.2m as was stated.I will allow that the rise would be a bit less than this because of the extra area of water after it has consume vast tracts of land through flooding, but the original statement of criticism is clearly not correct. The situation is much worse should the antarctic ice melt too by the way.
Perhaps I should run a poll on how many of us live below 50m above sea level.
I am in fact very happy that the Naked Scientist is free of fecal matter of any kind.
Oh! I guess he's not back yet. While we're waiting, here's a clue.Greenland has an area of 2.16 million square kilometers.Antartica has an area of 14 million square kilometers.So, assuming my $3 calculator is not lying again (it hasn't quite recovered from the coffee mug incident), Antartica could have 6.5 times as much ice as Greenland.Ignoring minor details like how thick the ice actually is, if it was ALL to melt we might conclude that sea level would rise by 45.5 m. Adding the 7 m or so from Greenland would make a total of 52.5 m.
I have every intention of continuing to overlook the effect of an increase in circumference that's roughly in proportion to the change in radius from 6378.1 km to 6378.2 km, not least because I live about 100m above sea level
Sorry I don't own a boat :p
Quote from: Eric A. Taylor on 23/11/2009 07:57:45I am in fact very happy that the Naked Scientist is free of fecal matter of any kind.I'm not sure I would go that far! Anyway, 2015 feet, ....erm, I meant to say 614 m
Quote from: Bored chemist on 23/11/2009 18:50:47I have every intention of continuing to overlook the effect of an increase in circumference that's roughly in proportion to the change in radius from 6378.1 km to 6378.2 km, not least because I live about 100m above sea levelYou may also want to overlook the fact that as the ice on Antarctica, and Greenland come to that, melts, the land surface will rise because it has a lot less weight to support. This increase in elevation will offset some of the tendency for the remaining ice to melt, but I doubt that it will be all that significant.Where are all the geologists when we need them? Off playing with their rocks, I suspect.BTW, at 100m you'll be pretty much "beachfront".
Quote from: Madidus_Scientia on 23/11/2009 18:16:57Sorry I don't own a boat :pNo, I meant you to take your plane. All Australians have planes so they can get around those gigantic sheep stations, don't they?
Oh, yes of course. Unfortunately my plane is not in working order at the moment, it was damaged by bunyips