Landscape: Antarctic Pressure Ridges

Snow and ice is nice…just about anywhere, but it becomes an even more beautiful landscape feature here in Antarctica. At this time of the year—late-summer now—the sea ice becomes unstable due to warmer temperatures. Seawater pushes against the ice edge and causes tidal waves to ripple through an icy crust. These waves eventually crack from the pressure when they reach the land, causing the ice to fracture into wily formations called pressure ridges:

These blocks of ice rise up from their pancake-flat surroundings and crack into jagged peaks, almost like ice sculptures. Here’s a closer look:

The pressure ridges are most pronounced near Scott Base, the New Zealand Antarctic station, just about 1.5 miles over the hill from where I live and work at McMurdo Station. Both bases are on Ross Island, which is webbed to the continent of Antarctica by a sea ice/ice shelf matrix. Also on Ross Island is Mt. Erebus, the southernmost active volcano, hovering here behind the Scott Base pressure ridges:

It’s a bit unsettling to know that pressure ridges are caused by cracks in the sea ice…and that they’re located in such close proximity to the area where we access ski routes on the ice shelf.

In order to leave Ross Island for the super-smooth Nordic skiing on the McMurdo Ice shelf, we have to walk or ski through the land-to-ice transition. My roommate, above, is tiptoeing through the slush. It’s safe—really, it is—but I sometimes feel like I’m going to step into a slush pool and fall all the way through the ice to the sea floor. So I tread carefully, prodding with my poles at any suspicious-looking pools of water. And then when I’m safely beyond transition, I simply enjoy the view.

One response to “Landscape: Antarctic Pressure Ridges

  1. whats the weather like

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