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Dispatch 1, from the Second Data-gathering Cruise of SO GLOBEC
April 9, 2002: It was hailed as an incredible feat in 1898 when explorers from a Belgian research cruise became the first humans to survive winter in the Antarctic. But plankton, penguins, and seals, among others wildlife, have for centuries "over-wintered" in Antarctica, despite fierce cold, raging winds, and months of darkness. In fact, the Southern Ocean, which surrounds Antarctica, is one of the world's most biologically productive regions. Today, the Southern Ocean Global Ecosystem Dynamics (SO GLOBEC) program is examining the extraordinary survival strategies of Antarctic creatures and their prospects in the face of potential climate change. This remarkable and complex scientific expedition left Punta Arenas, Chile this week for the Antarctic Peninsula, that portion of the continent that extends northward towards South America. Two National Science Foundation (NSF) research vessels, the Laurence M. Gould and the Nathaniel B. Palmer, will house about 100 scientists and support crew for the next six weeks. Scientists will repeat and refine data and sample collections and experiments conducted last year in SO GLOBEC's inaugural research season, applying some lessons learned in the harsh Antarctic conditions. "This is a real tough environment that doesn't treat your hardware very nicely," said Peter Wiebe, of the Woods Hole Oceanographic Institution, who is the Palmer's chief scientist. The productivity of the Southern Ocean depends largely on an unassuming but abundant animal called krill. These small shrimp-like creatures are the key link in the Antarctic food web, in which nutrients from the water "feed" primary producers (algae and phytoplankton), which in turn feed krill, which in turn feed predators: fish, sea birds, penguins, seals, and whales. SO GLOBEC's central mission is to find out how and where krill live during the critical ice-covered winter period. But, beyond that, scientists hope to find out how krill are connected to the rest of the Antarctic animals and microorganisms and to the physics of the ocean. "There are people with expertise in all these areas on both of these ships," Wiebe said Peter Wiebe, of the Woods Hole Oceanographic Institution in Woods Hole, Mass, who is the Palmer's chief scientist. Working As a TeamThe Palmer and the Gould will work as a team. The Palmer will conduct a broad oceanic survey, collecting data along a series of points on fixed grid. The Gould will collect more focused data, spending four to five days at five stations in strategic locations. The study area centers on Marguerite Bay on the western side of the Antarctic Peninsula. Wiebe's team, aboard the Palmer, will map the distribution and abundance of krill and smaller plankton, including populations living under the ice. Others aboard the Palmer will count whales and sea birds from the Palmer's observation decks high above the ocean's surface. Ocean physics underlies the survival of all these species; for one thing, ocean currents bring in vital nutrients. John Klinck of Old Dominion University in Norfolk, Va., will lead a group of physical oceanographers who will scan the Bay looking for characteristic layers of warmer water -- a "balmy" 2 Degrees Celsius -- (35.6 Degrees Fahrenheit) that signal nutrient-rich water coming from the Atlantic. "As a student, I found it the most incredibly boring thing in the world to do these diagrams of temperature and salinity," Klinck admitted. But, he said, these diagrams actually tell an extraordinary tale. "Water from the surface of the North Atlantic becomes dense and falls to the bottom, slides down the Atlantic, goes round and round the Circumpolar Current [where warm northern waters meet cold Antarctic waters] and eventually comes up to the Antarctic shelf," Klinck explained. After hundreds to thousands of years in this system, this water has built up a rich nutrient base from degrading bacteria and plants. In addition to nutrients, the Atlantic water also brings heat, which can thin out sea ice. Since krill, as well as certain penguin species and mammals, require sea ice as a winter refuge, their populations might suffer if the temperature of this intruding water were to rise. "Last year at this time, there wasn't any ice. This time, we have a lot of ice. The contrast will be interesting," Wiebe said. Learning how krill respond to year-to-year variations in climate may help scientists predict their responses to prospective long-term climate change. How do krill survive the winter?Complementing the Palmer's large-scale survey, Gould scientists will focus on specific biological questions about how krill and other Antarctic animals meet the physical challenges of the Antarctic winter. For example, krill reduce their metabolism in the winter so they do not have to eat as much to survive, said Kendra Daly of the University of South Florida, who is sailing aboard the Gould. They can also feed on large masses of bacteria and algae that accrue on the bottom of sea ice if the ice sits around long enough. "It's kind of like spinach in your freezer," Daly said. Since food in the water column is extremely low in the winter, these "algal popsicles" are a key food source. In the absence of sea ice, or if sea ice forms late in the winter, this food source may diminish, affecting krill survival rates. Daly will measure krill growth rates, molting rates, and feeding rates. The Gould's chief scientist, Joseph Torres, of the University of South Florida, will measure krill metabolism rates. Torres will also lead a group scuba divers under the ice to study Antarctic fish up close. Among other adaptations, some Antarctic fish make antifreeze proteins that prevent their blood from freezing. A penguin group will brave the start of the Antarctic winter in tents. They will camp on land for two weeks to tag penguins and examine their stomach contents. "The penguin guys have a good idea what's going on in the system because their animals are sampling the same things my net's sampling," Torres said. A second group will camp at a separate location to tag seals. The Gould left on April 7, 2002, several hours behind schedule due to a weight problem. Crew removed rocks and gravel destined for Palmer Station for ongoing construction. The Palmer left port on April 9, 2002, right on time. The bright blue, green, red, and orange rooftops of Punta Arenas faded into the distance as the Palmer headed into the Straits of Magellan en route to the Drake Passage-- which contains some of the roughest seas in the world. The voyagers are as much adventurers as scientists as they prepare to take on the cold, rough seas of the Antarctic and even to camp on its lands or dive in its seas. But, then again, adventure is the heart of science.
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