The Arctic sea ice cover is undergoing significant climate-induced changes, resulting in a reduction in ice extent and a net thinning of the sea ice cover. During IPY researchers from 10 nations will be studying the properties and processes that govern this sea ice cover and exploring its role as an indicator and amplifier of climate change. Numerous techniques will be brought to bear on this task, including expeditions, satellite remote sensing, autonomous rovers, buoys, ocean moorings, and numerical models.

During glacial periods ice sheets move faster along so called ‘ice streams’. Ice streams leave footprints on the seafloor when the ice is grounded below the sealevel. This project aims at developing new models of fast ice flow in ice-streams based on analyses of the geological record of past ice-streams.

Recent changes in surface elevation and discharge speed in outlet glacier systems along the margins of the Greenland Ice Sheet have provided examples of dramatic localized shifts in the balance of ice discharge, surface melt, and accumulation. These rapid changes are in sharp contrast to relatively slow variations in surface elevation in the interior, which have been tied to accumulation and firn compaction variations on a decadal timescale. The challenge of documenting and attempting to understand the processes involved has motivated a large collection of proposed research projects aimed at this problem. These range from expansions of ongoing efforts to new projects, and from individual investigators to consortia from a number of nations. They utilize a range of observational and modeling techniques and exploit evolving capabilities in atmospheric modeling, remote sensing for measurement of ice motion and surface conditions, and surface-based and aircraft-based measurement techniques.

The salt content of sea ice is a major control on many climatically and biologically relevant processes (e.g., summer melting rates and surface albedo, the equilibrium thickness of multi-year ice, the formation of the brine channels that harbor microbial life in sea ice, the regulation of carbon fluxes between the atmosphere and ocean by maintaining brine network connectivity, the sea ice mechanical strength and, radiation scattering within the ice). In this project, we will study heat and brine fluxes through sea ice; two processes that are crucial for a better understanding of ice growth and melt dynamics.

This project links together multidisciplinary interests in the region of West Antarctica where the ice sheet discharges into the Amundsen Sea. It is one of the most active ice sheet areas, is already contributing a significant fraction of the increasing sea level, and holds the potential to dwarf other sea level contributions in the future. Aside from routine satellite coverage that monitor elevation and surface features, information about the area is limited. Our project will greatly advance our knowledge of ice dynamics of the area, the basal conditions, sub-shelf oceanic interactions, atmospheric transport of incoming snow, and historical record of ice extent. These studies will be conducted with the direct intention of supplying the involved modeling experts with necessary data to construct, initialize and validate advanced full-stress tensor models of ice flow.

GRACE (Gravity Recovery and Climate Experiment) is the first geodetic mission dedicated to the measurement of the time-variations of the Earth’s gravity field, it enables the detection of water mass transfers. The on-going GRACE mission (launched in 03/2002 for a nominal lifetime of 5 years; quasi-polar orbit) provides monthly maps of tiny spatio-temporal variations of gravity due to the redistributions of mass inside the surface fluid envelops of the Earth. These satellite measurements represent vertically-integrated gravity effects of water mass reservoirs (oceans, atmosphere, continental waters and ice sheets) and of the solid Earth that need to be unravelled.

SALE United International Team for Exploration and Discovery;

Subglacial Antarctic Lake Environments (SALE): A Unifying Phenomenon in Antarctic Earth Science

Beneath Antarctica's ice sheets, water has slowly accumulated over millenia pooling in catchment basins within the continental bedrock. Antarctic subglacial environments are natural macrocosms that, in some instances, trace their origins to more than 35 million years before present, when the continent became encased in ice. Life, especially microbial life, has successfully radiated into most aquatic habitats on Earth. There is little reason to doubt that subglacial environments are exempt from this process.The exploration and study of subglacial environments provides an unparalleled opportunity to advance our understanding of how the expression of life, the environment, climate evolution, and planetary history have combined to produce the world as we know it today.

OASIS will study the chemistry in the air over the Arctic Ocean. The health of mammals and humans is at stake, and a future change in climate will undoubtedly introduce unknown changes. OASIS will make use of a variety of platforms (icebreakers, ice islands, buoys) to obtain year-round information on the behavior of such key chemicals as ozone, mercury, and carbon dioxide. As the nature and extent of snow and ice cover is changing OASIS will assess the associated impact on, and by, climate change, and the human and ecosystem impacts of these chemicals.

Global Warming will have a large impact on glaciers in the Arctic region. Sea level will be affected, and substantial changes can be expected in sediment and fresh water supplies to embayments and fjords. In GLACIODYN we study the dynamics of Arctic glaciers by means of field observations, remote sensing from satellites, and computer modelling. This will deliver tools to make more accurate predictions about future changes.