Briar Wait
The geochemical extremes in Antarctic meltwater ponds over a seasonal cycle.
Briar Wait, Gateway Antarctica
Supervisors
Prof. Bryan Storey, Gateway Antarctica
Dr Jenny Webster-Brown, University of Auckland
Prof. Clive Howard-Williams, NIWA
Meltwater ponds are small inland water bodies dominated by cyanobacteria that have diverse physical and geochemical properties. This PhD research aims to fully characterise the geochemical extremes in Antarctic meltwater ponds over a seasonal cycle and to assess the ability of geochemical models to predict meltwater pond chemistry. This involves the development of a conceptual model to describe the annual freeze-thaw process in meltwater ponds near Bratina Island to enable a more realistic understanding of the processes affecting meltwater chemistry. Additionally, the geochemical model FREZCHEM will be validated using samples collected during the extended IPY field season to test its reliability for the prediction of winter brine conditions from summer bulk pond-water chemistry and, potentially, from summer surface water chemistry. Finally the relationship and degree of exchange between the inorganic and organic components of the carbon and nitrogen cycles in meltwater ponds will be investigated in order to determine the importance of biological processes on the major ion chemistry of the environment.
Research in 2008 focused primarily on the analysis and interpretation of the water samples collected in previous field seasons, finalization and modeling of the conceptual model of freeze and thaw, and thesis preparation.