Overview of Subglacial Lake Exploration
International Opportunities for Subglacial Lake
Exploration
By Mahlon C. Kennicutt II,
Geochemical and Environmental Research Group, Texas A&M University
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.
- 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.
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.
- Ask the organizers of the Amsterdam 2001 Biology Conference
to include a symposium on the subject, timed so that interested COMNAP members can attend
while in that country. This overture has been
made and the organizers have agreed.
- Request reports on activities related to sub-glacial lake exploration from interested national programs during the Amsterdam plenary, and keep the topic "Sub-glacial Lakes Exploration" as a standing item on the agenda of its annual meeting for the next few years.
- Request that SCAR agree to place the topic of next steps concerning sub-glacial lakes exploration on the agenda of the Joint SCAR/COMNAP Executive Meeting in Amsterdam. This request has been forwarded to the SCAR chair.
- Recommend joint SCAR/COMNAP workshop on sub-glacial lakes
exploration to be held in conjunction with the 2002 SCAR/COMNAP meeting in Shanghai.
- Place the topic "Sub-glacial Lakes" as a standing
item on the agendas for the annual COMNAP meeting.
Issue a COMNAP Notice in May requesting that National programs intending to become involved in sub-glacial lakes exploration submit a paper to COMNAP one month prior to the Amsterdam meeting outlining their plans.