Difference between revisions of "Ice-shelf"

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Typically, a shelf front will extend forward for years or decades between major calving events. Snow accumulation on the upper surface and melting from the lower surface are also important to the mass balance of an ice shelf. Ice may also accrete onto the underside of the shelf.
Typically, a shelf front will extend forward for years or decades between major calving events. Snow accumulation on the upper surface and melting from the lower surface are also important to the mass balance of an ice shelf. Ice may also accrete onto the underside of the shelf.


The density contrast between glacial ice and liquid water means that 1/9 up to 1/6 of the floating ice is above the ocean surface - depending on how much air at which pressure is contained in the bubbles within the glacial ice, stemming from compressed snow. The formula for the denominators above is 1/((ρseawater-ρglacial_ice)/ρseawater), density of cold seawater divided by kg/m3 is about 1.028 and that of glacial ice from about 0.85 to well below 0.92, the limit for very cold ice without bubbles. The height of the shelf above the sea can be even larger, if there is a lot of less dense firn and snow above the glacier ice.
The density contrast between glacial ice and liquid water means that 1/9 up to 1/6 of the floating ice is above the ocean surface - depending on how much air at which pressure is contained in the bubbles within the glacial ice, stemming from compressed snow. The height of the shelf above the sea can be even larger, if there is a lot of less dense firn and snow above the glacier ice.


The world's largest ice shelves are the Ross Ice Shelf and the Filchner-Ronne Ice Shelf in Antarctica.
The world's largest ice shelves are the Ross Ice Shelf and the Filchner-Ronne Ice Shelf in Antarctica.