Impuretés solubles contenues dans la glace de l’Antarctique

Ionic concentrations in the ice (down to 100 meters deep) and in the firn of the eostal region of Terre Adelie have been studied. The results show that the concentration found in the upper layers of the ice is sensibly the same as that found in locally accumulated layers of the firn. The principal ions, of which average concentration is always less than 1 mg/l, are in order of their importance Cl, Na, and SO₆ and then K and Ca. The ice in lower layers, originating by way of ice flow from inland area of Antarctica, contains three times less impurities. The concentration of SO4 ions then becomes predominant (0.24 mg/l). The possible origin of these different ions is discussed. Important variations in their concentration observed at one station do not seem to be linked to a seasonal phenomenom.

On the base of published data, it has been estimated that every year approximately 4·10⁶ tons of soluble impurities are deposited on Antarctica. These impurities take part in a cycle, but the ice of this continent could contain up to 19·10⁹ tons of soluble salts.