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An interdisciplinary research team collected water and ice cores to study the microbial communities found in the Transantarctic Mountains and the McMurdo Dry Valleys in Antarctica. Once believed to be devoid of life, closer observations of glacial ice have revealed microhabitats teeming with life. In these extreme conditions, microorganisms live in the liquid water phases of ice, and they depend upon dissolved organic matter (DOM) in the water for food and nutrients. Although DOM is found in every environment and is an important component of the global carbon cycle, we still need more basic information about it, such as how DOM forms and changes over time.

The research team compared the microbes and DOM in two different types of Antarctic streams: normal streams that flow out of a lake and a supraglacial stream that forms on top of a glacier each summer. Because the supraglacial stream forms each year from a relatively clean surface, the investigators had a unique chance to study how the microbial community and DOM start from scratch and develop over time. By isolating the DOM and studying its chemical and structural composition, the team learned more about how the contributions and interactions between microbes and the DOM pool are different in the two different types of streams.

In addition, it is not well known how DOM and carbon locked in glacial ice will respond to climate change. The connection between ice-bound DOM and climate change is important because frozen environments comprise 25% of the Earth's surface, potentially releasing additional carbon into the atmosphere as global temperatures warm.

A large international team of scientists and drilling technicians worked throughout the austral summer to continue to assemble and test the world's largest scientific instrument, the in-ice IceCube Neutrino Detector. Neutrinos are incredibly common (about 10 million pass through your body as you read this) subatomic particles that have no electric charge and almost no mass. They are created by radioactive decay and nuclear reactions, such as those on the sun and other stars. Neutrinos rarely react with other particles or forces; in fact, most of them pass through objects (like you, or the entire earth) without any interaction. This makes them ideal for carrying information from distant parts of the universe, but it also makes them very hard to detect. All neutrino detectors rely on observing the extremely rare instances when a neutrino does collide with a proton. This collision transforms the neutrino into a muon, a charged particle that can travel for 5-10 miles and generate detectable light.

IceCube is being constructed in Antarctica because the huge amount of dense ice under the South Pole contains a lot of protons that can be hit by passing neutrinos, and the ice is transparent, so the resulting light can be caught by sensors. IceCube is made up of 4200 sensitive light detectors embedded in the ice at depths between 1450 and 2450 meters (4700-8000 feet). The sensors were deployed on strings of 60 modules each, into holes 60 cm. in diameter in the ice, melted using a hot water drill. Covering about one square kilometer, IceCube expands on an existing experiment that started detecting neutrinos at the South Pole in 1997 (http://

). Now complete, IceCube can detect up to 300,000 neutrinos a year for up to 20 years.

The data collected will be used to make a neutrino map of the universe and to learn more about cataclysmic astronomical phenomena, like gamma ray bursts, black holes, and exploding stars, and other aspects of nuclear and particle physics. However, the true potential of IceCube is discovery; the opening of each new astronomical window can lead to unexpected discoveries.

Initially, the CReSIS team worked at McMurdo Station preparing and outfitting a Twin Otter airplane with equipment that was used to conduct aerial radar surveys of glaciers at remote field camps. Since it was used as a platform for conducting the experiments, the airplane was mounted with instruments that measured ice thickness, mapped ice layers, and conducted SAR-imaging – a form of radar that produces high-resolution maps of the ice surface.

In early December 2009, after aircraft preparations were completed, the team traveled to Byrd Camp, a remote camp on the West Antarctic Ice Sheet, to conduct the aerial surveys. Each day (when weather permitted), the team took off, flew over area glaciers, and came back to camp. When they arrived back at camp, the team downloaded and processed the data that was collected by the instruments.

Although many of the areas that were surveyed were previously largely undiscovered, the survey work included flights over Thwaites Glacier (75.5°S 106.75°W). Part of the West Antarctic Ice Sheet, the Thwaites Glacier is one of the largest and most rapidly thinning glaciers in Antarctica.

At the core of CReSIS's work, the data collected during this project was integrated with other research efforts and data to create a 3-D visualization of the ice sheet to model and assess the potential impacts of ice sheets to future sea level rise.

Are microorganisms metabolically active in glacier ice? To address this exciting question, the research team traveled to the McMurdo Dry Valleys – one of the harshest environments on Earth – to study the biology, geology, and chemistry of basal ice – the dynamic layer of ice closest to the bedrock at the base of a glacier. The team used a tunnel cut into the side of Taylor Glacier to reach the basal ice layer. Data collected from field measurements and laboratory experiments helped researchers understand the connections between available nutrients, geochemical properties, and gas composition. This information helped determine if evidence for metabolism of microorganisms living in the ice could be found, and to link this to the types of cells present.

In addition, the research team investigated the similarities and differences among microorganisms in different types of ice within the basal ice zone. Some layers in the basal ice zone are clear and have little sediment. Other layers have high concentrations of debris. The basal ice zones of polar glaciers show similarities with the layered deposits evident in images of the northern ice cap on Mars. The findings from this project may be of interest to scientists studying potential habitats for microbial life on Mars and on the survival in of microorganisms in ice because the frozen environments in Antarctica and Mars may have many similarities.

The research team continued to explore remote regions of the seafloor around McMurdo Station, Antarctica with a remotely operated vehicle (ROV) for underwater research. The ROV was deployed through a small (15 cm) hole in the sea ice, enabling access to regions beyond scuba diving depths (at 40-170 m) and allowing the research team to survey very large areas of overlapping seafloor.

The research team used the ROV to locate historical experimental structures on the sea floor around McMurdo Station and to investigate the colonization of these structures by species of sessile invertebrates. The ROV was able to take videos and photographs of these ecological communities, which permitted the team to identify size, type, and species of organisms living on the structures. This provided an unprecedented opportunity to explore and document the rates and patterns of ecological succession from one of the most extreme habitats in the world.

The team also tested protocols for conducting sonar mapping with the new ROV as a first step towards creating high-resolution, bathymetric maps of the entire seafloor around McMurdo Station. The ROV's continued development and testing ensures its flexibility to be used for a variety of types of research projects in the future.

Learn more about Project SCINI at the official project website. 

Polar bears, Ursus maritimus, spend most of their time on the sea ice – where they travel, hunt, and sometimes even give birth. However, during the summer the sea ice retreats northward and leaves some polar bears on shore for several months. These bears may not be able hunt and may face warmer temperatures than they do on the ice. The research team investigated how the polar bears cope with these difficult conditions on shore, and attempted to determine if they possess adaptations similar to bears that hibernate in the winter.

A research team made up of scientists from the University of Wyoming, United States Geological Survey (USGS), and the United States Fish and Wildlife Service (USFWS) used the U.S. Coast Guard icebreaker Polar Sea and on-board helicopters to approach polar bears on the sea ice and collect measurements and samples to determine the overall physical condition of the animals. The research team recaptured bears that were originally tested in May 2009, to compare data from before and after the summer of 2009. Measurements included weight and length of the bear as well as overall appearance. In addition, the researchers measured body fat, muscle condition, and took blood samples.

Knowing how polar bears adjust when living on shore, and why they may not be able to adjust will provide important information to indigenous people, U.S. and international management agencies, conservation groups, and policy maker's for addressing the polar bear's needs in the future.