Conclusions

Despite temperatures well below the freezing point, the Antarctic continent possesses a wide variety of lakes (Figure 7) that contain liquid water throughout the year, making them an oasis for life in what would otherwise appear to be an uninhabitable environment. Interestingly, owing to their sensitivity to climate changes (small climate changes produce a magnified cascade of physical, chemical and biological changes), these lakes receive relatively little discussion in limnology textbooks. Antarctic lakes contain reservoirs of the evolutionary history of the continent and the contemporary activity we measure today often reflects the legacy of resources deposited in the environment during the evolution of the lake basins. Subglacial lakes, which have been isolated beneath the Antarctic ice sheet for >10 My, present an exciting new paradigm for limnologists. Recent calculations show that the subglacial lakes and rivers beneath the Antarctic ice sheet contain ~10 000 km3 of liquid water. This volume is ~10% of all lake water on Earth, enough to cover the whole continent with a uniform water layer with a thickness of m. Once sampled, information from these systems will change the way we view global water and biological reservoirs on our planet. Importantly, lakes in Antarctica provide clues on ecosystem properties and metabolic lifestyles that may exist on other frozen worlds such as Mars and Europa. As such, they provide us with a logical step in our search for extraterrestrial life.

Lake Ecosystem

Figure 7 Examples of different Antarctic lake types: (a) Lake Bonney an epiglacial lake, located in the McMurdo Dry Valleys is bound by both rock and glacier; the Taylor Glacier forms the lower boundary of the lake in the photo; (b) Radarsat image showing the flat area on the surface of the East Antarctic Ice sheet where the ice sheet 'floats' as it passes over the waters of Subglacial Lake Vostok; (c) Pony Lake is a shallow coastal lake at Cape Royds that freezes to the bottom in winter. Radarsat image is courtesy of NASA-GSFC. Shadows on the mountain side appear as dark blue areas in panel (a) and should not be confused with liquid water or dark mineral deposits.

Figure 7 Examples of different Antarctic lake types: (a) Lake Bonney an epiglacial lake, located in the McMurdo Dry Valleys is bound by both rock and glacier; the Taylor Glacier forms the lower boundary of the lake in the photo; (b) Radarsat image showing the flat area on the surface of the East Antarctic Ice sheet where the ice sheet 'floats' as it passes over the waters of Subglacial Lake Vostok; (c) Pony Lake is a shallow coastal lake at Cape Royds that freezes to the bottom in winter. Radarsat image is courtesy of NASA-GSFC. Shadows on the mountain side appear as dark blue areas in panel (a) and should not be confused with liquid water or dark mineral deposits.

See also: Effects of Climate Change on Lakes; Mer-omictic Lakes; Origins of Types of Lake Basins; Saline Inland Waters.

Was this article helpful?

0 0
Project Earth Conservation

Project Earth Conservation

Get All The Support And Guidance You Need To Be A Success At Helping Save The Earth. This Book Is One Of The Most Valuable Resources In The World When It Comes To How To Recycle to Create a Better Future for Our Children.

Get My Free Ebook


Post a comment