Description
Dorthe Dahl-Jensen, NEEM, U of Copenhagen 20 mins
Frank Pattyn, U Libre Brussels 20 mins
Jean-Robert Petit, LGGE - CNRS, U J Fourier-Grenoble 20 mins
Buford Price, IceCube, UC-Berkeley 20 mins
Dorthe Dahl-Jensen
(Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen)
28/04/2011, 09:00
Ice Cores
A new Greenland ice core has been drilled. The first results from the NEEM ice core are presented and then combined with results from other deep ice cores from the Greenland Ice Sheet.
All of the ice cores drilled through the Greenland Ice Sheets have been analyzed, and the results show that all contain ice from the previous warm Eemian period near the base. Is it thus clear that the...
Frank Pattyn
(Laboratoire de Glaciologie, U Libre Brussels)
28/04/2011, 09:20
Ice Cores
Subglacial conditions of large polar ice sheets remain poorly understood, despite recent advances in satellite observation. Major uncertainties related to basal conditions, such as the temperature field, are due to an insufficient knowledge of geothermal heat flow. We use a hybrid method that combines numerical modeling of the ice sheet thermodynamics with a priori information, using a...
Jean-Robert Petit
(UJF-Grenoble)
28/04/2011, 09:40
Ice Cores
Polar ice sheets and glaciers contain well-ordered archives of ancient ice that fell as snow, from recently to millions of years ago. The ice composition and impurities, along with the gasses entrapped in air bubbles together provide a unique history of past climate changes and environmental and atmospheric composition. The study of deep ice cores revealed the close link between temperature...
Prof.
Buford Price
(U. C. Berkeley)
28/04/2011, 10:00
Ice Cores
Oxygen-producing cyanobacteria originated on Earth around two billion years ago. Two genera of oceanic submicrometer-size cells -- the Synechococcus and the Prochlorococcus -- account for as much as half of the air that we breathe. Winds transport them from polar oceans onto Arctic and Antarctic glacial ice. We find that they are present in the glacial ice at all seven sites and all depths we...
