Premium
Dissolved gas dynamics in perennially ice‐covered Lake Fryxell, Antarctica
Author(s) -
Hood E. M.,
Howes B. L.,
Jenkins W. J.
Publication year - 1998
Publication title -
limnology and oceanography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.7
H-Index - 197
eISSN - 1939-5590
pISSN - 0024-3590
DOI - 10.4319/lo.1998.43.2.0265
Subject(s) - neon , anoxic waters , supersaturation , geology , photic zone , noble gas , oceanography , atmospheric sciences , argon , chemistry , phytoplankton , organic chemistry , nutrient
We use the concentrations of noble gases (He, Ne, and Ar), helium isotopes, and tritium to characterize the mechanisms and rates of ventilation for Lake Fryxell, Antarctica, as well as the physical processes controlling dissolved gases. The upper oxic zone is ventilated on timescales of several decades. The anoxic bottom waters are weakly ventilated, with a turnover time of ∼3,800 years. In the upper euphotic zone, helium and neon are greatly undersaturated with respect to solubility equilibrium with the atmosphere, whereas argon is greatly supersaturated owing to equilibrium partitioning of the gases between ice, water, and air inclusions in the ice. In the bottom waters, the inert dissolved gas concentrations may be remnants of a near‐desiccation event that occurred ∼2,000 years B.P., consistent with current paleoclimatic theories.