The National Academies Press

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1 Introduction
Pages 11-31

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From page 11... ... From geophysical surveys, we now know that beneath the Antarctic ice sheet, water has accumulated over millennia forming watery subglacial environments ranging in size and form from Lake Vostok, a large water body similar in surface area to Lake Ontario, to shallow frozen swamp-like features the size of several city blocks. The discovery of subglacial aquatic environments has opened an entirely new area of science in a short period of time. Read the entire page →
From page 12... ... From a scientific perspective, they may hold critical information needed to answer many questions about microbiological life, evolution, and adaptations; Antarctic and global climate over the past 65 million years; ice sheet dynamics; and evolution of subglacial aquatic environments and their associated hydrological and biogeochemical processes. Scientific interest in the subglacial hydrology of ice sheets has never been higher, because we need to learn as much as possible about how the subglacial water systems operate beneath ice sheets. Read the entire page →
From page 13... ... Use of this technique across the Antarctic ice sheet provided, for the first time, the possibility of mapping the whole of the underlying continental rock (Robin 1972) Read the entire page →
From page 14... ... The next step proposed is to drill an additional 75 m to obtain new scientific data on the origin, properties, and structure of the ice near the "ice cover-subglacial lake" bound ary. The proposed method to access Lake Vostok will exploit the physical peculiarities of the lake-ice sheet system. Read the entire page →
From page 16... ... Phase 1 -- Geophysical Exploration (3 years) : The size and shape of Lake Ellsworth, flow of the ice sheet over the lake, and subglacial topography surrounding the lake will be measured. Read the entire page →
From page 18... ... The advent of satellites with radar altimeter sensors able to measure the height of the ice sheet surface to within a few centimeters has provided a complementary approach to locating such lakes, because the flat lake surface is apparently reflected in the ice surface topography kilometers above it. In 1993, altimetric data from satellite Read the entire page →
From page 19... ... Using RES and satellite altimetry together, the location and extent of this subglacial lake, now named Lake Vostok, was described by Kapitsa et al. Read the entire page →
From page 20... ... Microorganisms are continually deposited from the atmosphere onto the surface of the ice sheet (Vincent 1988) and some may survive the lengthy transport to subglacial aquatic environments, thereby providing a potential source of microbial life to these environments. Read the entire page →
From page 21... ... Many of these sites are located within suspected drainage basins of identified subglacial aquatic environments. Liquid water is able to accumulate at the bottom of the ice sheets, including the Greenland ice sheet, because of the presence of geothermal heat, the lowering of the freezing temperature of water from the pressure of the overlying ice, and the insulation provided by the ice sheet (Siegert et al. Read the entire page →
From page 22... ... 1.04 The region with the highest spatial density of subglacial water bodies surrounds what is likely to have been one of the nucleation points for the East Antarctic ice sheet. Subglacial aquatic environments located in these regions may contain sediments that accumulated prior to ice sheet formation and may potentially contain paleo-records of major shifts in climate. Read the entire page →
From page 23... ... During the Cambridge workshop (1999) , the scope of investigation was expanded beyond just Lake Vostok to include all subglacial lakes under thick ice sheets. Read the entire page →
From page 24... ... • Encourage adherence to the agreed guiding principles of exploration and research on sub glacial lake environments, especially environmental stewardship. • Be an advocate for exploration of subglacial lake environments in all venues, including na tional committees, scientific communities, and the public, and establish scientific liaisons and logistics cooperation with other Antarctic entities and activities as appropriate. Read the entire page →
From page 25... ... SCAR continues to serve as the international focal point of activities to facilitate cooperation in the exploration and study of subglacial lake environments in Antarctica, advising the international community on issues related to exploration, research, data management, and other matters. In addition, members of the U.S. Read the entire page →
From page 26... ... Siegert (2002) applied the first five questions to the inventory of known subglacial lakes to identify which were the most suitable subglacial aquatic environments for exploration. Read the entire page →
From page 27... ... For most subglacial aquatic environments, the glaciological setting has been rudimentarily described through RES surveys. However, there are very few detailed geological data from beneath the Antarctic ice sheet, and this lack of data inhibits our ability to characterize the geological setting in which these environments are contained and to understand the geological history of these environments. Read the entire page →
From page 28... ... The Antarctic ice sheets are a critical part of the Earth's hydrological balance, as well as the most important heat sink. The continent provides an opportunity to measure baseline global pollution levels, and the measurements of greenhouse gases at the South Pole have been a key feature of research into global climate change. Read the entire page →
From page 29... ... has requested guidance from the National Academies to address the environmental and scientific protection standards necessary to responsibly explore the subglacial lake environments found under continental-scale ice sheets. In response, the National Research Council of the National Academies created the Committee on the Principles of Environmental and Scientific Stewardship for the Exploration and Study of Subglacial Environments. Read the entire page →
From page 30... ... This report addresses the environmental and scientific protection standards needed to responsibly explore the subglacial aquatic environments. The motivations for this study are to ensure wise stewardship of these unique environments, including strict observance of environmental protection responsibilities under domestic and international laws and treaties, and to determine how to collect the best possible samples for scientific study while minimizing site contamination and ensuring preservation for future scientific inquiry. Read the entire page →
From page 31... ... The committee acknowledged that the scientific investigation of subglacial aquatic environments has previously been vetted internationally through the Antarctic Treaty Protocol and exploration has been accepted as a legitimate activity. The charge to the committee was concerned with how to undertake such an activity while maximizing the overall protection of this particular environmental resource. Read the entire page →

From page 11...

... From geophysical surveys, we now know that beneath the Antarctic ice sheet, water has accumulated over millennia forming watery subglacial environments ranging in size and form from Lake Vostok, a large water body similar in surface area to Lake Ontario, to shallow frozen swamp-like features the size of several city blocks. The discovery of subglacial aquatic environments has opened an entirely new area of science in a short period of time.

1 Introduction Pages 11-31

1 Introduction
Pages 11-31