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The research team worked out of Barrow, Alaska, at the juxtaposition of two Arctic seas; the Chukchi and Beaufort Seas. It is a region frequently traveled by the endangered bowhead whale. This project had its genesis in understanding why the region near Barrow, Alaska is a feeding hotspot for migrating bowhead whales, and the whales and their prey will continue to be a focus of the team's interpretations. The research team conducted oceanographic sampling of the physical and biological marine environment in the region over the period 2005-2011 and observed significant inter-annual variability. Long-term studies of the ocean conditions in the Arctic are needed in order to understand how these environments vary inter-annually. The research team will continue to document conditions in the biological-physical ocean ecosystem, through annual boat-based surveys in order to predict and understand potential impacts of climate change on the Arctic ecosystem.

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Titulo financiado: Observación anual del medio ambiente marino biológico y físico en los mares Chukchi y Beauford en las cercanías de Barrow, AK.

El equipo de investigación viajará por avión a Barrow, una comunidad pequeña de aproximadamente 4,500 habitantes en la costa norte de Alaska. Como permitan las condiciones del tiempo, el equipo se embarcara para la colección de muestras oceanográficas a bordo del buque de investigación Annika Marie de 43 pies. Las actividades de a bordo incluirán colección de agua y plancton y mediciones de conductividad, temperatura, y profundidad. A bordo también tomarán nota sobre las ocurrencias de mamíferos marinos y realizarán el procesamiento preliminar de muestras. Si el clima es malo para navegar en el océano ellos pasarán el tiempo en Barrow catalogando muestras y organizándose para los días que pasaran sobre el agua.

If the Antarctic ice sheet were to collapse or melt substantially it would impact all of humankind. This research attempts to reconstruct the paleogeography of parts of Antarctica while trying to determine the physical conditions that led to formation of the Antarctic ice sheet.

The past opening of deep Southern Ocean gateways between Antarctica and South America and between Antarctica and Australia permitted the complete circulation of the Antarctic Circumpolar Current (ACC). This opening may have been critical in the transition from a warm Earth in the past, to the subsequently much cooler conditions that persist to the present day. The opening of Drake Passage and the West Scotia Sea probably broke the final barrier formed by the Andes of Tierra del Fuego and the 'Antarctandes' of the Antarctic Peninsula. It is thought that once this deep gateway, usually referred to simply as the Drake Passage gateway (DPG), was created, the strong and persistent mid-latitude winds likely generated one of the largest deep currents on Earth. This event is widely believed to be closely associated in time with a major, abrupt drop in global temperatures and the rapid expansion of the Antarctic ice sheets 33-34 million years ago. On an earlier cruise to the Central Scotia Sea on board Nathaniel B. Palmer, however, Dalziel and Lawver and their colleagues found evidence that there may have been a barrier to eastward flow from Drake Passage to the South Atlantic Ocean basin until 10-12 million years ago when the planet descended even more deeply into an 'icehouse' state.

The research team dredged seafloor samples and analyzed them for their age and composition to determine if they may indeed have once blocked the Antarctic Circumpolar Current. They mapped the sub-seafloor to see how and/or if South Georgia is colliding with the North East Georgia Rise and with their co-investigator Robert Smalley of the University of Memphis they installed three GPS units on South Georgia to determine its horizontal and vertical motion. It is notable that the mountains of the island, which the explorer Ernest Shackleton and his companions had to cross after their celebrated small boat journey from Antarctica, are three times as high as the equivalent part of the Andean Cordillera in Tierra del Fuego.

The oldest fossil life on Earth consists of stromatolites, which are the remains of complicated communities of bacteria captured in rock. On modern Earth, similar communities still grow in places that are too harsh for worms, snails, and other grazing animals to live and eat them. Lakes in Antarctica with liquid water below a few meters of ice almost always support these communities. Thus, they provide the opportunity to study the ecology of microbial communities like those on early Earth billions of years ago.

The research team studied the communities in Lake Joyce, Antarctica in several different ways. They took images of the stromatolites in Lake Joyce and reconstructed the 3D morphology of microbial mats in the lake. They also characterized the environment that the stromatolites are growing in and studied how the morphology of the stromatolites varies mud deposition and calcite mineral formation. They also directly sampled the stromatolites to study the distribution of photosynthesis, calcite mineral formation, and mud incorporation.

They expect this study to make several important contributions to understanding early life on Earth. Morphological studies of the stromatolites will provide insights into how microbial communities build intricate structures and how variations in environment and ecology affect morphology. Results will also help researchers understand how microbial communities influence calcite mineral growth and how this affects stromatolite morphology. Results will be directly applicable to better interpreting ancient stromatolites, providing insights into ecological and biogeochemical processes on early Earth. Finally, a better understanding of the processes by which microbial communities build stromatolites will aid in the search for evidence of life on other planets, such as Mars, where landed missions have access to sedimentary rocks.

How do you find something that isn't directly visible? That's the challenge faced by the team who developed the IceCube neutrino detector under the ice at the South Pole. Just as X-rays allow us to see bone fractures, and MRIs help doctors find damage to soft tissue, neutrinos will reveal new information about the universe that can't be seen directly. The in-ice particle detector at the South Pole records the interactions of neutrinos which are nearly massless sub-atomic messenger particles. Neutrinos are incredibly common (about 100 trillion 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 in the sun and other stars. Neutrinos rarely react with other particles; in fact, most of them pass through objects (like the 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 interact with a proton or neutron. This transforms the neutrino into a charged particle of the same type as the neutrino flavor (electron, muon, or tau). Muons are charged particles that can travel for 5-10 miles (8-16 kilometres) through matter depending on their energy, and generate detectable light in translucent media.

IceCube is made up of thousands of sensitive light detectors embedded in a cubic kilometre of ice between 1450 m and 2450 m below surface. The sensors are deployed on strings in the ice holes that were made using a hot water drill. IceCube detects about 100,000 neutrinos a year, and has a projected life time of two decades. The data collected will be used to make a "neutrino map" of the universe and to learn more about astronomical phenomena, like gamma ray bursts, black holes, 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 leads to unexpected discoveries.

The movement of warmer ocean water through or around relatively cooler ice sheets has the potential to lead to increased melting of the ice sheets. This project will determine the potential vulnerability of key ice streams to the infiltration of warmer ocean water and whether this could explain any of the observed thinning of the ice sheet. It will provide important information about a particular section of the East Antarctic Ice Sheet and therefore will be critical for future ice sheet models and investigations into the ice sheet's contributions to sea levels.

Microbial diversity has recently been found to show a pattern of organization at various scales. The research team attempts to answer three basic questions about microbial diversity and dispersal, focused on the long-term aspects of dispersal events and climate change: 1) How does environment influence microbial community composition and rate of function? For example, how quickly they convert organic material to carbon dioxide. 2) How are distribution patterns of microbial communities in lakes, streams, and soils influenced by the dispersal from local water flow? 3) How are the shifts in microbial community composition related to shifts in environmental conditions over time such as those caused by climate change?

To date, the researchers have found that microbial communities in lakes and rivers change dramatically through the seasons but reassemble on an annual basis. They have also found that community composition in soil and surface waters shifts within days in response to environmental fluctuations in temperature or dissolved organic matter composition. They have also found that upland terrestrial habitats act as landscape-level seedbanks for lowland aquatic systems. The ultimate goal of the project is to develop a greater understanding of the controls on microbial community composition and function over space and time.

The research focuses on the interactions between plants and their pollinators, which are animals that aid in plant reproduction through transporting pollen. The aim is to understand how changes in temperature and precipitation may influence plant-pollinator interactions and plant reproduction. Temperature and water availability may alter the timing of flowering and floral traits that attract pollinators, such as nectar volume and flower size. In addition, temperature may alter what pollinator species visit flowers and how often they visit. The combination of these effects on plants and pollinators may influence plant reproduction, measured as the number of fruits and seeds a plant produces. The researchers hope to relate changes in the abiotic environment to floral attractive traits, pollinator visitation, and ultimately the reproductive success of plants. Three focal plant species, blueberry, harebell, and dwarf fireweed are used because they are common in the area and flower at different times of the season.

This work can have important pan-Arctic and global implications. The majority of flowering plants in nature and one third of our crop plants depend on pollinators to produce fruits and seeds. As temperatures rise in the Arctic, successful adaptation and range expansion of many plants, including plants migrating into the Arctic, will depend on pollinators. This study will help us determine which mechanisms may most strongly drive changes in plant-pollinator interactions and plant reproduction.

In the Arctic, bright summers and dark winters are a fact of life and can lead humans to rely on clocks and routines to tell them when to eat or sleep, but how do animals function under these conditions? Circadian rhythms refer to the "internal body clock" that regulates the approximately 24-hour cycle of biological processes in animals and plants. Rhythms in body temperature, brain wave activity, hormone production, and other biological activities are linked to this 24-hour cycle. The Earth's light-dark cycle provides the strongest influence on circadian rhythms and is thought to be the primary driver for the emergence and evolution of internal clocks. In the Polar Regions, however, photoperiod exhibits extreme annual variation because of near 24 hour sunlight in the summer and 24 hour darkness in the winter. In the absence of a well-defined light-dark cycle, some arctic residents lose their daily organization of behavior and physiology, and it is thought that the molecular clockwork that drives circadian rhythms may be weak or absent in arctic vertebrates.

The research team has recently found that the arctic ground squirrel displays daily rhythms of body temperature throughout the arctic summer, in the absence of a light-dark cycle. The current study will investigate the circadian rhythms in arctic ground squirrels during the continuous daylight present during the active summer season and continuous dark of the 6-8 months of hibernation spent sequestered in a burrow. The team wants to understand why arctic ground squirrels, unlike other arctic vertebrates, appear to maintain 24-hour rhythms during the active season. They hypothesize that the persistence of circadian rhythmicity allows ground squirrels to reduce energy expenditure by anticipating predictable changes in its immediate surroundings. They are testing their hypothesis by experimentally phase-shifting free-living ground squirrels to be active at 'night' and estimating their subsequent rates of energy expenditure.