lakes potentially contain sediments within their lake beds that may provide a record of major changes in the Antarctic ice sheet.
On the basis of the limited data we have so far, however, there seem to be several exciting scientific discoveries to be made from the study of these unique systems, especially the potential for unique microbial communities, a general understanding of the physiochemical processes of this extreme environment, and a history of environmental conditions from the sediment record. The discovery of subglacial aquatic environments, especially lakes, and the intriguing questions posed about these extreme environments have caught the attention of the public.
There is great value in setting the exploration of these environments in motion. 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. The question of whether ice sheets can have a large dynamic response to changes at their margins (e.g., the breakup of ice shelves) partly involves the question of whether or not fast flow processes will be activated by changes in subglacial conditions. Thus, there are conceivable links to the important question of sea level rise. It is important for us to acquire this information in the next 5 to 10 years—not several decades from now.
During the Lake Vostok investigation (Box 1.1), data will be gathered that may help determine whether microbial life is present or absent from this environment. Chemical analyses of water samples will help settle speculative discussions about partition coefficients, which will improve geochemical modeling of these environments. The exploration plans for Lake Ellsworth (Box 1.2) call for a concentrated radio-echo sounding (RES) campaign followed by physicochemical and biological measurements and water and sediment sample recovery. With results of both of these investigations, we will only begin to develop an initial understanding of these environments, but these first samples will provide all-important evidence about how conservative we should be in moving forward. The data and lessons learned from these endeavors should be used to guide future environmental stewardship, scientific investigations, and technological developments.
The pursuit of scientific knowledge, however, needs to be balanced against environmental stewardship and cleanliness. Responsible stewardship during the exploration of subglacial aquatic environments requires that investigators proceed in a manner that minimizes the possible damage to these remarkable habitats and protects their value for future generations, not only in terms of their scientific value but also in terms of conserving and protecting a pristine, unique environment. This is particularly important because it now appears that these environments are hydrologically and potentially biologically connected and that activities at one site may affect other sites within the system.
No lake has yet been entered, thus no lake has been directly altered, chemically or biologically, by scientific study. It is to minimize the possible damage to these remarkable habitats from scientific investigations and protect their value for future generations that this National Research Council (NRC) study has been undertaken.