National Geographic
Menu

Expedition Antarctica: On Thin Ice

By Christine Dell’Amore

Christine Dell’Amore is participating in a National Science Foundation media trip to report on scientists conducting polar research near McMurdo Station, Antarctica.

Thumbnail image for expeditionantarctica_border.jpg

Today truly felt Antarctic. So far the weather’s been no worse than a wintry day in D.C., but a storm barreled in this morning that is like nothing I’ve experienced–winds that suspend you in mid-stride; heavy, wet snow; and a disorienting lack of visibility. Contrary to what most might think, Antarctic snowstorms never dump several feet of snow–a little bit falls here and there, which the wind then blows across the landscape.

Helicopters were grounded for the second day, another discouraging development for our trip to the Dry Valleys. But we arranged a last-minute tour of the ice shelf’s pressure ridges, which form when glaciers collide with the frozen sea.


me-with-pressure-ridge.jpg

Me with the ice ax–I certainly got use out of it!

From land, the strangely shaped pillars rising from the ice look like entries in some sort of extreme ice-sculpture competition. It’s hard to imagine how the explorers plowed right through them on their way to the South Pole.

We set out with Mike Santos, McMurdo’s recreation manager, who handed us ice axes and a warning to stay clear of meltwater pools. Then he promptly fell into a pool himself. He was a hardy Antarctican, of course, and we pushed on, testing any questionable-looking ice with our ax edge as we trudged toward the ridge. “And you thought the ice axes were just for photo ops,” Santos shouted as we climbed over an ice wall. Suddenly we arrived in what looked like a Dr. Seuss fantasy world, surrounded by jagged, icicle-trimmed towers and fluorescent blue ponds.

Watch Mike Santos explain how pressure ridges are formed.

Santos pointed out a Weddell seal–the southernmost seal species–a few hundred feet away, and with my 200mm lens I could see him on his back, seemingly clapping his flippers at our impressive hiking skills. Scientists at McMurdo are attaching cameras to these seals–which can usually be found hanging out near the pressure ridges–to find out more about their lives underwater.


seal.jpg

A Weddell seal rests on the pressure ridge

The snow came down harder as we picked our way along the narrow, flag-marked paths, and Santos decided to call it a day. Later he told us our trip was the most challenging pressure ridge hike he’d done–and that it was the last of the summer season.

 


hiking-pressure-ridge.jpg


Hiking through the pressure ridge–the “trail” is marked by flags
 

In the early afternoon I caught a ride up to the Arrival Heights station, an atmospheric research facility on a wind-scoured hill above McMurdo. Inside the lab, research associate Chris Young showed us various instruments that measure the amount of UV light, wind velocity, and low-frequency waves from Earth’s ionosphere, among others. One of the scientists, University of Washington’s Michael McCarthy, gave me a crash course in the ionosphere, a layer of charged particles that begins about 53 miles (85 kilometers) up in Earth’s atmosphere. Since this region can conduct electricity, any changes in its electrical power can impact radio transmissions on Earth, for example television and GPS. That’s why a thunderstorm–what McCarthy called a “great big impulsive radio transmitter”–can suffuse the ionosphere with new energy and affect our GPS signals.

 

Watch Chris Young talk about measuring wind

Jammed GPS signals are the least of our worries tomorrow, when weather may doom our last chance to see penguins before my afternoon flight back to Christchurch. My return flight may be canceled too, which would force me to leave Monday. We’ll see what happens, but I can think of worst things than being stuck in Antarctica!

Photos by Christine Dell’Amore

Christine Dell’Amore is the environment writer/editor for National Geographic News.