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Pressure from the McMurdo Ice Shelf pushing the sea ice against the shore of Ross Island is so intense that it pushes the ridges of ice very high in the air - the formations are constantly changing, and always beautiful.

Exploring the Pressure Ridges of McMurdo Sound

In McMurdo Sound, the McMurdo Ice Shelf cascades into the sea. pushing and squeezing the frozen sea ice against the hut point peninsula where McMurdo Station and Scott Base are located. This pushing and squeezing of the floating sea ice creates dramatic pressure ridges in the ice, which are beautiful and memorizing to explore. A few nights ago I had the opportunity to walk amongst the pressure ridges and take some pics…

From Wikipedia:

214px-Pressure_ridge_(ice)_Geometry_Drawing.svgPressure Ridges – A pressure ridge develops in an ice cover as a result of a stress regime established within the plane of the ice. Within sea ice expanses, pressure ridges originate from the interaction between floes,[note 1] as they collide with each other.[3][4][5][6] Currents and winds are the main driving forces, but the latter are particularly effective when they have a predominant direction.[7] Pressure ridges are made up of angular ice blocks of various sizes that pile up on the floes. The part of the ridge that is above the water surface is known as the sail; that below it as the keel.[note 2] Pressure ridges are the thickest sea ice features and account for about one-half of the total sea ice volume.[2] Stamukhi are pressure ridges that are grounded and that result from the interaction between fast ice and the drifting pack ice.[8][9]

Mcmurdo_sound_USGS_mapMcMurdo Sound – McMurdo Sound and its ice-clogged waters extends about 55 kilometres (34 mi) long and wide. The sound connects the Ross Sea to the north with the Ross Ice Shelf cavity to the south via Haskell Strait. The strait is largely covered by the McMurdo Ice Shelf. The Royal Society Range rises from sea level to 4,205 metres (13,796 ft) on the western shoreline. Ross Island, an historic jumping-off point for polar explorers, designates the eastern boundary. The active volcano Mt Erebus at 3,794 metres (12,448 ft) dominates Ross Island. Antarctica’s largest scientific base, the United States’ McMurdo Station, as well as the New Zealand Scott Base are located on the southern shore of the island. Less than 10 percent of McMurdo Sound’s shoreline is free of ice.[1] It is the southernmost navigable body of water in the world.[2]

Entering the ice ridges on the frozen sea ice of McMurdo Sound. Colored flags mark the way through the ridges, on areas known to be solid. Amongs the ridges are huge cracks in the ice, leading to think ice and the Ross Sea.
Entering the ice ridges on the frozen sea ice of McMurdo Sound. Colored flags mark the way through the ridges, on areas known to be solid. Amongs the ridges are huge cracks in the ice, leading to think ice and the Ross Sea.
Melt Pools form in the low sections of the ridges. It's in these melt pools that Weddle Seals make holes from the Ross Sea onto the ice. Here you can see two seals hanging out on the ice.
Melt Pools form in the low sections of the ridges. It’s in these melt pools that Weddle Seals make holes from the Ross Sea onto the ice. Here you can see two seals hanging out on the ice.
Seals on the Ross Sea ice
Seals on the Ross Sea ice
Taking pictures of seals, with New Zealand's Scott Base in the background. Humans aren't allowed to get much closer to wildlife, and the seals don't really acknowlage our presence there.
Taking pictures of seals, with New Zealand’s Scott Base in the background. Humans aren’t allowed to get much closer to wildlife, and the seals don’t really acknowlage our presence there.
Me, walking through the inter-ridge trough.
Me, walking through the inter-ridge trough.
Pressure from the McMurdo Ice Shelf pushing the sea ice against the shore of Ross Island is so intense that it pushes the ridges of ice very high in the air - the formations are constantly changing, and always beautiful.
Pressure from the McMurdo Ice Shelf pushing the sea ice against the shore of Ross Island is so intense that it pushes the ridges of ice very high in the air – the formations are constantly changing, and always beautiful.
Beautiful structures created in the Ross Sea ice ridges.
Beautiful structures created in the Ross Sea ice ridges.
Through various freeze/thaw cycles, beautiful patterns emerge in the ice near Scott Base.
Through various freeze/thaw cycles, beautiful patterns emerge in the ice near Scott Base.

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