A firsthand look at the effects of climate change near the South Pole.
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Last month, Radarsat-2 completed a new mapping mission of Antarctica, and the Canadian Space Agency is planning to process the data and develop new maps, establishing comparative data sets 12 years apart.Skip to next paragraph
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Robert Saint-Jean, manager of radar data in the Satellite Operations Directorate of the Canadian Space Agency, says Radarsat-2 can image down to three feet. “One of the main technical advantages of Radarsat-2 is the ability to slew – to turn and look at the left side of its track. Usually synthetic aperture radar systems look to the right side. This enables us to observe the central part of the Antarctic continent on a day-to-day basis, mapping the interior of the continent for the very first time.”
Mr. Jezek and the Canadian Space Agency are spearheading efforts to coordinate the imaging activities of Earth observation satellites in the US, Europe, and Asia, so that each “bird” images a distinct Antarctic region, avoiding duplication.
From one bay to the next, the Europa drops anchor in front of enormous glaciers plunging down to the sea at very high angles. “You have all of these pull-apart crevasses,” says Mr. Stewart, the boatswain, who trained as a geologist, “all of them parallel to the shore, parallel to the toe of the glacier, and these will just fall away all at once, like bookshelves in a library dropping down. It sounds like rifle shots.”
According to Europa’s captain, Klaas Gaastra, a giant iceberg calving off a glacier last year set off a 15-foot impact wave that could have overturned the ship. Fortunately, there was just enough time to let out all the anchor cable.
Evgeniyy Karyagin is the base commander at Ukraine’s Vernadsky station, on the west side of the Antarctic Peninsula. Formerly known as Faraday Station, the base was transferred from Britain to Ukraine in 1996. Researchers here focus on atmospheric and climate research.
Mr. Karyagin brings his experience as a seismologist for the Ukrainian National Space Agency to study what he calls “ice quakes” – nontectonic seismic events caused by the glacier movements.
“I receive signals from the iceberg-generation process,” he says. “The whole coast of the Antarctic Peninsula has many glaciers, each of which drops a big weight of ice into the water, generating a very small signal like an earthquake. Every day, I receive about 1,000 to 2,000 such signals. If I count the number of signals I receive from glaciers, I can measure the total weight of freshwater reaching the ocean in the form of ice.”
Rick Atkinson, manager of Port Lockroy – once a British scientific base but now a heritage site welcoming 15,000 cruise-ship tourists each summer – says that his area has seen warmer temperatures recently. “This last winter, our automatic weather recorders here told us that the coldest temperature all winter was only 6 degrees F., and most of the time it was just around freezing, or just below.”
As the Europa nudges into smaller pieces of ice, they make a crackling sound as air bubbles trapped inside are released by the sun and water.
“Is the breakup of Antarctic ice shelves a cause for concern?” Jezek asks. “Expressed in that way, I find [that] people become unduly worried.... I prefer to think of it as an observation that should be considered and planned against. Sea level will surely continue to rise, and this will have an impact on coastal communities. What we need to do now is better refine our estimates of the rate of that change so that people can intelligently plan.... I think people in general will be more receptive to that message instead of some of the gloom and doom you often see reported.”