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International Polar Year 2007–2008 - WMO

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252<br />

IPY 20 07–20 08<br />

Emerging Subglacial Exploration<br />

Programs<br />

Significant progress has continued on subglacial<br />

lake exploration after the IPY period. Almost a decade<br />

of planning has led to the funding of major new programs<br />

to study various aspects of subglacial aquatic<br />

environments. These programs are in addition to continuing<br />

efforts at Lake Vostok. An ambitious U.K.-led<br />

program will survey and sample Subglacial Lake Ellsworth<br />

in West Antarctica in the next few years with<br />

lake entry predicted in 2011-2012. The geophysical<br />

studies of Lake Ellsworth have shown it to be 10 km<br />

long, 2-3 km wide and at least 160 m deep (under 3 km<br />

of ice). Surveys confirmed that sedimentary deposits<br />

can be expected on the floor of the lake. The surrounding<br />

topography revealed that the area is an ancient<br />

fjord developed at a time when an ice cap occupied<br />

the Ellsworth Mountains prior to the development of<br />

the West Antarctic ice sheet. Geophysical surveys confirmed<br />

that the lake has likely persisted through glacial<br />

cycles. The project will access the lake using clean hotwater<br />

drilling and deploy a probe to sample and measure<br />

both the water and sediment. Lake penetration<br />

and in situ sensing and sampling should take place<br />

in 2012. On a similar time scale, the U.S. has funded a<br />

further program (WISSARD) to enter, instrument and<br />

sample an ‘actively discharging’ subglacial aquatic<br />

system beneath Whillans Ice Stream, which is also in<br />

West Antarctica. Russian researchers had hoped to<br />

penetrate Lake Vostok during IPY, but were beset by<br />

technical problems so they are now developing a new<br />

strategy for lake penetration and sampling.<br />

References<br />

Alekhina I.A., D. Marie, J.R. Petit, V.V. Lukin, V.M. Zubkov<br />

and S.A. Bulat, 2007. Molecular analysis of bacterial<br />

diversity in kerosene-based drilling fluid from the<br />

deep ice borehole at Vostok, East Antarctica. FEMS<br />

Microbiology Ecology, 59:289-299.<br />

Bell, R and D.M. Karl, 1998. Lake Vostok Workshop: A<br />

Curiosity or a Focus for Interdisciplinary Study? Report<br />

to the National Academies: Washington D.C.<br />

Bell, R.E., M. Studinger, M.A. Fahnestock and C.A. Shuman,<br />

2006. Tectonically controlled subglacial<br />

A New Frontier in Antarctic Science is<br />

Advanced by IPY<br />

The IPY period saw the development of significant<br />

new insights into the importance of subglacial aquatic<br />

environments including:<br />

• subglacial lakes were common features of ice sheets,<br />

• a spectrum of subglacial environments exists,<br />

• subglacial hydrologic systems and water movement<br />

beneath ice sheets on various spatial and temporal<br />

scales were common,<br />

• subglacial lakes may be linked with the onset of ice<br />

streams influencing ice sheet movement, and<br />

• outbursts of subglacial waters could have feasibly<br />

played a role in past climate change.<br />

The exploration and study of subglacial aquatic environments<br />

is at its earliest stages and if the major advances<br />

realized during IPY are any indication of what<br />

is to come, the most exciting discoveries will unfold in<br />

the years ahead. In just a decade, findings regarding<br />

subglacial aquatic environments have revolutionized<br />

how Antarctica is perceived (Fig. 2.6-6). Ice sheets are<br />

now seen as exhibiting a highly dynamic behaviour<br />

and the environments beneath them may play critical<br />

roles in fundamental processes that affect the complex<br />

interplay of geology, glaciology, tectonics, ecology and<br />

climate over geologic time. On-going and planned<br />

projects will ultimately determine if subglacial environments<br />

house unique microbiological assemblages, but<br />

these programs would not have been possible without<br />

the momentum provided by the IPY.<br />

lakes on the flanks of the Gamburtsev Subglacial<br />

Mountains, East Antarctica. Geophys. Res. Lett., 33:<br />

L02504.<br />

Bell, R.E., M.Studinger, C.A. Shuman, M.A. Fahnestock<br />

and I. Joughin, 2007. Large subglacial lakes in East<br />

Antarctica at the onset of fast-flowing ice, Nature,<br />

445: 904-907.<br />

Bell, R.E., M. Studinger, A. Tikku, G.K.C. Clarke, M.M. Gutner<br />

and C. Meertens, 2002. Origin and fate of Lake<br />

Vostok water frozen to the base of the East Antarc-

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