@article {3211, title = {Carbon Sequestration and Release from Antarctic Lakes: Lake Vida and West Lake Bonney (McMurdo Dry Valleys)}, journal = {Aquatic Geochemistry}, volume = {19}, year = {2013}, month = {03/2013}, pages = {135 - 145}, abstract = {

Perennial ice covers on many Antarctic lakes have resulted in high lake inorganic carbon contents. The objective of this paper was to evaluate and compare the brine and CO2\ chemistries of Lake Vida (Victoria Valley) and West Lake Bonney (Taylor Valley), two lakes of the McMurdo Dry Valleys (East Antarctica), and their potential consequences during global warming. An existing geochemical model (FREZCHEM-15) was used to convert measured molarity into molality needed for the FREZCHEM model, and this model added a new algorithm that converts measured DIC into carbonate alkalinity needed for the FREZCHEM model. While quite extensive geochemical information exists for ice-covered Taylor Valley lakes, such as West Lake Bonney, only limited information exists for the recently sampled brine of \>25\ m ice-thick Lake Vida. Lake Vida brine had a model-calculated pCO2\ =\ 0.60 bars at the field pH (6.20); West Lake Bonney had a model-calculated pCO2\ =\ 5.23\ bars at the field pH (5.46). Despite the high degree of atmospheric CO2supersaturation in West Lake Bonney, it remains significantly undersaturated with the gas hydrate, CO2\·6H2O, unless these gas hydrates are deep in the sediment layer or are metastable having formed under colder temperatures or greater pressures. Because of lower temperatures, Lake Vida could start forming CO2\·6H2O at lower pCO2\ values than West Lake Bonney; but both lakes are significantly undersaturated with the gas hydrate, CO2\·6H2O. For both lakes, simulation of global warming from current subzero temperatures (\−13.4\ \°C in Lake Vida and \−4.7\ \°C in West Lake Bonney) to 10\ \°C has shown that a major loss of solution-phase carbon as CO2\ gases and carbonate minerals occurred when the temperatures rose above 0\ \°C and perennial ice covers would disappear. How important these Antarctic CO2\ sources will be for future global warming remains to be seen. But a recent paper has shown that methane increased in atmospheric concentration due to deglaciation about 10,000\ years ago. So, CO2\ release from ice lakes might contribute to atmospheric gases in the future.

}, keywords = {LTER-MCM}, issn = {1380-6165}, doi = {10.1007/s10498-012-9184-1}, url = {http://link.springer.com/10.1007/s10498-012-9184-1http://link.springer.com/content/pdf/10.1007/s10498-012-9184-1}, author = {G. M. Marion and A. E. Murray and Wagner, Bernd and Christian H. Fritsen and Kenig, Fabien and Peter T. Doran} } @article {1293, title = {Comment on {\textquoteleft}{\textquoteleft}El Ni{\~n}o suppresses Antarctic warming{\textquoteright}{\textquoteright} by N. Bertler et al.}, journal = {Geophysical Research Letters}, volume = {32}, year = {2005}, pages = {L07706}, keywords = {LTER-MCM, Tropical meteorology}, doi = {10.1029/2004GL021716}, author = {Peter T. Doran and Gary D. Clow and Christian H. Fritsen and Christopher P. McKay and Andrew N. Parsons and John C. Priscu and W. Berry Lyons and Walsh, J and Andrew G Fountain and Diane M. McKnight and Daryl L. Moorhead and Ross A. Virginia and Diana H. Wall} } @article {1450, title = {Carbon transformations in a perennially ice-covered Antarctic lake}, year = {1999}, keywords = {LTER-MCM}, author = {John C. Priscu and Craig F. Wolf and Cristina D. Takacs-Vesbach and Christian H. Fritsen and Johanna Laybourn-Parry and Emily C. Roberts and Birgit Sattl} } @article {1490, title = {Cyanobacterial assemblages in permanent ice covers on Antarctic lakes: distribution, growth rate, and temperature response of photosynthesis}, journal = {Journal of Phycology}, volume = {34}, year = {1998}, pages = {587-597}, keywords = {LTER-MCM}, author = {Christian H. Fritsen and John C. Priscu} }