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Welcome to an Operation IceBridge sea ice interlude.

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We start with a visualization of AMSR-E data from the Aqua satellite,

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showing sea ice, or frozen seawater, pulsing over the course of months

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around the Antarctic continent.IceBridge often passes around the Antarctic continent.IceBridge often passes

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passes the scenic Antarctic Peninsula on its way to survey the continent’s ice sheets, glaciers,

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Usually the peninsula's mountains are shrouded by clouds

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but today we have a clear view.

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As we descend, we see vast fields of sea ice, which comes in an array of shapes

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and thicknesses. Large pieces of sea ice are called floes

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and these formations often collide, creating thick ridges along their edges,

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or raft over top of each other.

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This ice appears to be thick enough to be 2nd-year ice, or ice which survived a summer melt season.

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Darker, grayer ice

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appears to be more recent, and might be around 10 cm thick,

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while the white ice covered by snow is probably more than 30 cm thick.

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The area in the lower center here is so smooth,

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it might just be a few hours old.

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This is frazil ice. It’s granular,

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like a slushy beverage, and is created by very dynamic conditions

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of turbulence in the water.

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This is a region of brush, containing sea ice and a few icebergs.

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IceBridge measures Antarctic ice from 500 meters above the surface, using

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radar, laser altimetry, and with these crisp images

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from the DMS or Digital Mapping System.

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Here we have ice that’s holding fast to the shore,

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and immobilizing icebergs from a nearby glacier or ice shelf.

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These slabs of ice from continental ice shelves,

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sticking above the water by perhaps 50 meters

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are large and flat enough to be called tabular bergs.