Department Lecture Series (DLS) – John Priscu (MSU)

“Geobiology of Antarctic Subglacial Environments: An historical perspective”

Antarctica is the highest, driest and coldest continent on earth. It holds 90% of our world’s ice and 70% of its freshwater. If the ice melts, sea level will rise about 60 m and inundate more than 12 million km2 of land. The early explorers referred to it as a place devoid of life. The idea that the Antarctic ice sheet was lifeless persisted for more than 80 years, when the first explorers stepped foot on the continent. Recent research has now shown that huge river basins and some of our planet’s largest lakes exist beneath more than 4 km of Antarctic ice providing new information on the stability of the West Antarctic Ice Sheet and biodiversity on the continent. Collectively, these data reveal that subglacial aquatic ecosystems in Antarctica form the largest wetland on our planet. Given the isolated, dark and frigid conditions presented by this environment, we do not find catails and red winged blackbirds, common to surface wetlands; instead, the environment is completely microbial. These organisms mine the energy in rocks and in relict marine sediments to obtain energy to support their existence, while at the same time mobilizing nutrients that fuel life in the coastal regions of Antarctica. Data from biogeochemical experiments together with prokaryotic single cell genomics and metagenomic data on viruses will be presented to describe what is currently known about the biogeophysics of the Antarctic subglacial environment.

ABOUT THIS SERIES:
[DLS] EAPS Department Lecture Series

Weekly talks aimed to bring together the entire EAPS community, given by leading thinkers in the areas of geology, geophysics, geobiology, geochemistry, atmospheric science, oceanography, climatology, and planetary science. Runs concurrently with class 12.S501.

Contact: eapsinfo@mit.edu