Image of the Day: Retreat of Sea Ice in McMurdo Sound, Antarctica, 2003-2011
Caption by Holli Riebeek
March 10, 2011 Early in February 1902, Captain Robert Falcon Scott sailed into McMurdo Sound and docked his ship, the Discovery, in a small, sheltered bay at the tip of a rocky peninsula on Ross Island. Eager to begin a year exploring one of Earth’s last untouched places, Scott and his men immediately set to work building a hut to serve as the base for the 47 men on the expedition. The peninsula became Hut Point Peninsula. While the men were taking scientific measurements and scouting the alien landscape, sea ice formed over McMurdo Sound, trapping the Discovery. The following summer, Scott discovered that sea ice around Hut Point Peninsula does not disappear every year. In fact, if Scott had made his expedition in 1998, he would only now be free. In 2011, sea ice in McMurdo Sound reached its lowest extent since 1998, reported the United States Antarctic Program. It is the first time that the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor, which launched on NASA’s Terra satellite in late 1999, has seen the tip of Hut Point Peninsula free of ice. Sea ice in McMurdo Sound fluctuates from year to year based on local currents and weather patterns. For much of the past decade (shown in the animation), the giant B-15 iceberg altered currents and trapped sea ice in McMurdo Sound. Sea ice still clogged the Sound when MODIS acquired the top left image on March 3, 2003. The iceberg broke apart in 2005, and the largest piece is visible in the 2006 image. Though the Sound was clearer in 2006, Hut Point Peninsula was still solidly encased. From 2008 through 2010, late-summer sea ice around Hut Point Peninsula changed very little. In the final image in the series, from February 25, 2011, the point of the peninsula is surrounded by open water. … [T]he breaking sea ice posed transportation problems for modern explorers at McMurdo Station in 2011. The ice broke enough that parts of Pegasus airfield had to be relocated just as scientists and crewmembers were leaving the station on airplanes at the end of the summer, said the U.S. Antarctic Program.
