Subglacial Antarctic Lake Environments (SALE) have attracted great scientific and public interest in recent years.
SALE will be a focus of scientific and engineering exploration and research in Antarctica for the next decade or more. SALE will be a key element of the IPY 2007-2008 scientific theme - exploring new frontiers. There is a need for the world-wide Antarctic science community to better organize and coordinate their efforts in this important and emerging arena of polar science, engineering, and education. To assist in organizing SALE efforts, Texas A&M University has established the SALE Program Office (PO) as a focus for all aspects of SALE exploration and research. The SALE Program Office creates synergy by serving the US community, the recently approved SCAR international Scientific Research Program - SALE and the IPY coalition of seven countries - SALE-UNITED (SALE Unified International Team for Exploration and Discovery). The SALE PO will act as a clearing house for all SALE interests including being the point of contact for the ICSU/WMO Joint Committee during the IPY2007-2008. The SALE PO provides a central location for interested parties to find and communicate information about SALE exploration and research. The SALE PO will also facilitate partnerships, cooperation, and coordination as the broader SALE agenda unfolds over the next several years.
Subglacial Lake Research and Exploration......
The exploration of subglacial lakes has caught the imagination of the scientific and lay public. The high level of interest has been generated by speculation about the possibility of life in the lake being isolated for hundreds of thousands of years and its potential analogy to other ice covered world's in the solar system, such as Europa a moon of Jupiter. Plans by the scientific community to explore subglacial lakes have been advanced by a series of workshops that have been convened starting in 1996. The first wide publicity about the possible presence of a large lake under the East Antarctic ice sheet was engendered by the article of Kapitsa et al. in the journal Nature in 1996 (Volume 381:684-686). Subsequent to this article, the presence of the lake was reported during the Rome meeting of the Scientific Committee on Antarctic Research (SCAR). Following several workshops, activities culminated with an international workshop in Cambridge in 1999. From this meeting a scientific plan was produced and suggestions were made for a phased-in approach to implementation of a comprehensive subglacial lake exploration program. This report has been widely distributed (Kennicutt et al, 2000).
The workshop report and science plan suggested that subglacial exploration must be international in participation, interdisciplinary in scope, use non-contaminating techniques for lake entry and sample retrieval, and that Lake Vostok should be the ultimate exploration target. The report recognized that successful exploration of subglacial lakes would require sizeable and sustained resources to attain the wide ranging scientific objectives of such a program. While a number of specific scientific objectives were described they fall into three categories: the detection and characterization of life in the lake, recovery of the paleo-climate record that may be present, and development of a better understanding of the tectonics of Antarctica. The overarching research theme was how the evolution of life, climate and tectonics interacted to produce the unusual physical/chemical settings now known as subglacial lakes.
As far as implementation of an exploration plan, it was recognized that many challenges would need to be addressed. A mechanism for international coordination would have to be devised to encourage broad participation in the project through sharing of implementation and logistical costs. It was also recognized that significant technological challenges will need to be overcome and that the best approach was a phased-in approach that included funding of corollary or supporting projects (such as aerial surveys), technology development and tests in analogous settings, exploration of smaller lakes, and final entry into Lake Vostok. First entry and exploration might best be accomplished by remote sensing or robotic techniques and sample retrieval may be postponed until after initial exploration efforts have been accomplished.
One area that warrants significant investment is the development of the technologies needed to conduct subglacial lake exploration. The remoteness and the difficulty of the challenge to enter the lake, retrieve water, pass through the lake and retrieve sediment, and do all of this through four kilometers of ice in a way that prevents lake contamination is a no small order. It was recognized that much of the technology needed does not now exist. Enabling technologies include access methodologies (ice drilling), non-contaminating systems and procedures, robotics and in situ sensors, sample retrieval techniques, and miniaturization of sensors and sampling devices. Given these technological challenges it was recommended that more accessible analogous settings such as those that may be available in northern regions be used as test sites. Northern ice shelves, frozen lakes, and glaciers may be effective proving grounds for new technologies. As the effort proceeds to Lake Vostok, additional tests on the ice shelves of the southern ocean, in smaller more accessible lakes and other analogous settings would be appropriate to prove new technologies.
The workshop produced a series of recommendations that include SCAR's appointment of an international group of specialists, encouragement of scientists and National Antarctic committees to engender support for the program in their home countries and constituencies, and a request to the Council of Managers of National Antarctic Programs (COMNAP) to assist in technology development and planning of logistics. At the SCAR meeting in Tokyo in the summer of 2000 a Group of Specialists on Subglacial Lakes was formed. As of this report the Group has not officially met, although a tentative meeting is set for September 2001 in Bologna, Italy. COMNAP has deferred the convening of a technology workshop until the problems are more completely defined. Various countries are forming working groups and advancing the cause of subglacial lakes through their national agencies and support mechanisms. The US will most likely convene a series of workshops to address specific issues related to subglacial lake exploration including sterile entry and sample retrieval methods, drilling technologies, and robotics and in situ sensors.
It is clear that a comprehensive, interdisciplinary subglacial lake exploration program is a major undertaking. It is recognized that the accomplishment of the broad objectives envisioned may well take a decade or more to complete. However, the first steps have already begun. The US has funded improved aerial radar surveys of Lake Vostok and plans are under way to fund a wide array of corollary and supporting projects in other countries. While it may be a while before an international collaborative mechanism is agreed to conduct subglacial lake exploration, interested parties should be developing plans to contribute to the wide range of challenges that will need to be addressed if this ambitious program is to be accomplished.
Scientific Goals
Determine the form, distribution, and activity of life in the lake water, the sediment below, and the ice above.
Recover climatic information contained in ice overlying the lakes and sediment underlying lakes.
Understand the origins of subglacial lakes and their impact on the evolution of life under the ice.
Stages of Exploration
Lake Vostok is the largest of the known subglacial lakes, and is a logical long-term target for subglacial exploration through in situ instrumentation and sample return. However, there are clear benefits to a staged, progressive scientific program that includes:
Reconnaissance and mapping in analogue settings;
The exploration of smaller lakes and possibly ice shelves;
In situ sensing of the water, sediments, and overlying ice of subglacial lakes;
Examination of water and sediment properties in several subglacial lakes;
Water and shallow (<10 m) sediment retrieval; and finally,
Deep sediment (10-500 m) retrieval. |
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