It is 20 years since subglacial Lake Vostok in central East Antarctica
was found to be one of the world’s largest freshwater bodies (Kapitsa et al.,
1996). It was hypothesized to be both an ancient, extreme yet viable environment
for microbial life, and a recorder of past climate change. Testing
these hypotheses is possible with direct measurement and sampling, but
in-situ examination is challenging because of the thick ice to drill through,
the necessary cleanliness required of the experiment, and the extreme
polar conditions in which to operate. In this issue of Geology, Michaud
et al. (2016, p. 347) report on water and sedimentary material collected
in January 2013 from Lake Whillans, a component of the hydrological
system beneath Whillans ice stream in West Antarctica. They reveal the
water comprises melted basal ice and a small proportion of seawater, the
concentration of which increases with sediment depth, making it unique
among known subglacial environments within and outside of Antarctica.
Here, to place the Lake Whillans work in context, I discuss the range of
Antarctic subglacial lake environments, showing the continent to contain
an assortment of systems in which novel physical, chemical, and biological
processes may take place.