Description
Summary:This dataset contains temperature profile data from 16 saline lakes of the Vestfold Hills, Antarctica. The data were obtained during the 1985-86 summer season and the latter half of 1987. These lakes can be grouped into two classes: those with maximum salinities (anywhere in the water column) greater than 100g kg-1 (ppt) and those with less. The saltier group are usually shallower, tend to be warmer in summer, colder in winter and have thinner ice cover. Salinity gradients in the water column can completely dominate temperature gradients as determinants of density and thus warmer water is not infrequently found beneath colder water. Temperature, in this situation, can be a sensitive tracer of brine movements. Winter freeze-out of brines during the growth of surface ice can produce both a deepened well-mixed layer and discrete brine flows from the lake edge to intermediate depths of equivalent density near the lakes deepest point. The process is clearly shown in the profiles of Organic Lake. This dataset provides thermal structure data for the sixteen lakes studied in the Vestfold Hills. Other previous studies have investigated biological and physical properties of these lakes. Depth and temperature profile measurements were made at 16 saline lakes, while they were covered with ice. Holes were drilled using a Jiffy ice Drill, and the zero level for each cast was taken at the water/ice interface. All temperatures are reported in degrees centigrade. During the 1995-96 summer season, temperature and depth data for the profiles (except for Pendant Lake) were measured using a Yeo-Kal model 606 submersible data logger (SDL). The SDL was usually lowered in discrete intervals and held stationary for 15-20 seconds, providing 3 to 4 temperature and depth registrations for each depth, only one data point for each depth is given. Temperature measurements at Pendant Lake were made using a Phox oxygen/temperature metre model number 62 TE. In 1987, profiles were taken using a Platypus conductivity-temperature-depth recording unit (Platypus Engineering, Loyetea, Tasmania). The unit was lowered in measured 10 cm intervals and held at each depth for 30 seconds, recording every 5 seconds. The online data also provides data for other parameters. The fields in this dataset are: Depth Temperature Lake Salinity Oxic/Anoxic Boundary Mixing Status