Where's the Melt Factor in Antarctica?
July 23, 2012 --
This week Google debuted a new set of panoramic images from the South Pole. Taken in partnership with on-site researchers from the University of Minnesota’s Polar Geospatial Center, these interactive views shed light on remote locations such as Ernest Shackleton’s early shelter and the Adélie penguin rookery. The images were captured using off-the-shelf equipment that included a digital SLR camera with a fisheye lens, said Alex Starns, a Google technical program manager for Street View whose work covers operations in Asia Pacific and Antarctica. Brad Harried, a researcher with the Polar Geospatial Center, took the latest photos. “Brad would often carry extra batteries in his pocket and use a chemical hand warmer to keep them from freezing,” Starns said. “It’s a little challenging to operate the camera wearing thick winter clothes and mittens.” Explore the frigid Antarctic landscape in this slide show of high-resolution images.
The South Pole Telescope building shown here contains an enormous scientific instrument that took more than 30 engineers and scientists to construct. “The South Pole Station is actually at a really high altitude,” Starns said. Located 1.7 miles above sea level, the telescope is used by a team of scientists seeking to answer crucial questions such as “How old is the universe?” Since the South Pole has such clear atmosphere, it’s an ideal location for observing the thermal radiation that fills our universe. Starns hopes that Street View users who interact with the new images from Antarctica will be excited to learn more about the continent. He also wants them to have a greater appreciation for the explorers of 100 years ago and modern researchers, he said. Particularly the challenges inherent in a place NASA scientists used to prepare the landers for conditions on Mars. ANALYSIS: 100 Years Ago Today: Scott Reaches South Pole
Anglo-Irish explorer Ernest Shackleton survived what seemed like certain death. His first attempt to reach the South Pole in 1901 nearly killed him. In 1908 he returned, getting even closer to the South Pole. Although Norwegian explorer Roald Amundsen got there first in 1911, Shackleton was still determined. His ship Endurance would get trapped in the ice, forcing the crew on an epic adventure to safety. New images show the entire interior of Shackleton’s 1908 hut at Cape Royds. “Having this immersive imagery of the supply depot they built really reinforces the sense of just how incredible that journey was,” Starns said. Reading materials remain on the beds, tossed aside as if their owners will be back momentarily. And yet the objects inside hut have stayed in place for more than a century. “His
was unique because they had some early photographic equipment on board,” Starns said of Shackleton. “In the hut you can still see some of the photographic chemicals that they used to develop their film.” Photographer Frank Hurley’s images from the Endurance expedition would become famous. HOWSTUFFWORKS: Can You Vacation in Antarctica?
A 50-foot-long wooden cabin was built in 1911 at Cape Evans on Ross Island to house several dozen men. British explorer Robert Falcon Scott used this building as a base for his Terra Nova expedition to the South Pole, but he and his team ultimately reached the pole weeks after Amundsen. Scott and the four other men in his party died in the frozen wilderness while attempting to return. A letter found with his body read, "Had we lived, I should have had a tale to tell of the hardihood, endurance, and courage of my companions which would have stirred the heart of every Englishman." Although the cabin has remained largely unchanged since Shackleton locked it up in 1917, scientists have to regularly keep it from being swallowed by ice and snow. "You look at the food and the equipment that they brought and imagine how isolating and how lonely it must have been down there," Starns said, adding that he couldn’t imagine spending years eating tea biscuits and gravy. "It’s amazing to me that not only did these men do this, but many of them volunteered for it." NEWS: Two Aussies Reach South Pole Unaided
Back in 2010, Google first unveiled Street View images taken from Half Moon Island on the northern edge of the Antarctic Peninsula. Visitors from cruise ships that stopped there helped take the panoramic photos at the time, Starns said. Instead of a human, the Street View icon turned into a little penguin. The Adélie penguins at a remote rookery on Cape Royds aren’t accustomed to humans taking their pictures, but they seem more focused on soaking up the summer sun. From here the waters of McMurdo Sound are visible. Adélie penguins use the sun to navigate from land to the sea, according to scientific data from the Polar Conservation Organization. Unlike the humans in Google’s shots, none of the penguins have blurred faces to protect their identities. “If we get any blurring requests from them, we’ll be sure to tend to them,” Starns joked. ANALYSIS: Paralyzed Athlete Sit-Skis to the South Pole
Flags from the nations that signed the Antarctic Treaty encircle the Ceremonial South Pole. In 1959 the original treaty among 12 nations included provisions stating that Antarctica would only be used for peaceful purposes and ensuring continued scientific research there. Since then, the list of signatories has grown to 50. Besides flags, the Ceremonial South Pole is marked by a pedestal with a reflective globe on top. In the background stands the Amundsen-Scott South Pole Station, an American scientific facility. When the Google panoramic images were shot on the polar plateau, the conditions weren’t just windy -- the temperature was negative 60 degrees F. The ice that the station is built on moves annually so the geographic South Pole location is in a different position every year, Starns said. "The ceremonial pole always stays in the same place." VIDEO: Frozen Planet: Journey to the South Pole
The Arctic Ocean is entering its spring melt season, after reaching a winter maximum that was the sixth lowest in the satellite record and that appears to have left the North Pole covered, not by thick multi-year ice but by thin first-year ice. Meanwhile, instead of contracting, sea ice around the continent of Antarctica continues to expand in extent ever so slightly.
As we’ve explained previously, there is an enormous difference between the degree to which Antarctic sea ice is expanding (to a slight but statistically significant degree) and Arctic sea ice is declining (catastrophically). Furthermore, there are fundamental differences between the very nature of sea ice at both polar regions – notably the fact that Antarctica as a continent is surrounded by ice that largely drifts away and melts each summer, and doesn’t generally have the kind of multiyear ice that is disappearing from the Arctic. So the comparison isn’t apples-to-apples.
Even so, explaining the mechanism responsible for the relative stability of Antarctic sea ice – even as some Southern Ocean temperatures increase – is something that has been occupying a number of researchers. A British Antarctic Survey study led by Paul Holland late last year concluded that changes in local wind patterns were spreading the ice out across a greater area. An earlier study by the Georgia Institute of Technology proposed that warmer Antarctic air temperatures are creating greater precipitation, which falls as snow insulates the region’s sea ice cover from warming from below.
This theory addresses an important distinction between the thermodynamics of Arctic and Antarctic sea ice; in the words of Georgia Tech’s Judith Curry, “In the case of the Arctic most of the melting is driven from the warmer atmosphere above. In the Antarctic most of the melting has been driven from the ocean below.” This warming sub-surface water has been implicated in the demise of some West Antarctic glaciers and has also been observed to be impacting glaciers in Greenland.
Now a new theory expands on the impact of that deeper, warm water. According to Richard Bintanja and colleagues at the Royal Netherlands Meteorological Institute, glacial melting is causing the spread of plumes of cold surface water, which – similar to the effect hypothesized by Curry and colleagues at Georgia Tech – is insulating the ice from the warmer waters below and, being cooler, is freezing more easily in fall and winter, thus ensuring a continuing supply of fresh ice.
Of course, the climate is a complex system and it doesn’t necessarily follow that these assorted theories are mutually exclusive (although this latest study suggests that colder surface waters would result in less water evaporating and falling as snow). Holland, the British Antarctic Survey researcher, responded to the new study by saying that, ”The possibility remains that the real increase is the sum of wind driven and melt-water driven effects, of course. That would be my best guess, with the melt water effect being the smaller of the two.”
Photograph of an icebreaker in early-season sea ice in Antarctica’s Ross Sea, by Kieran Mulvaney.