This data package contains chemical characteristics of water samples collected along four supraglacial streams on Canada Glacier, located in Taylor Valley, McMurdo Dry Valleys, Antarctica. Samples were collected during the 2015-16 and 2016-17 austral summers in order to characterize the spatial and temporal evolution of glacial meltwater as it travels over and off Canada Glacier. Samples from the 2015-16 austral summer have been fully analyzed and those data are included here. Samples from the 2016-17 austral summer have been stored frozen since collection and have not been analyzed. This package may be amended in the future if analysis of the 2016-17 samples occurs.
This package contains data from 40 sampling sites, with 10 sites each on four streams on Canada Glacier. Stream 1 drains the southwest part of the glacier, stream 2 drains the southeast corner, stream 3 drains the northwest side of the ablation zone, and stream 4 drains the northeast side of the ablation zone.
Samples were collected in triple DI-washed 500 ml polyethylene bottles. In some cases, an ice lid had to be chopped away with an ice axe to access liquid water. In cases where the stream was too narrow or shallow to fill the bottle, the bottle was filled using water scooped with the bottle cap. These conditions are indicated in the notes. After collection, samples were brought back to the field camp where water was distributed into a 20 ml glass scintillation vial, one triple DI-washed and one acid-washed 60 ml polyethylene bottle, and one acid-washed 125 ml bottle. The scintillation vial was stored at 4º C, all polyethylene bottles were frozen at -20º C, and all samples were shipped back to Boulder, Colorado for further analyses. One 60 ml bottle was thawed at 4º C in the Crary lab at McMurdo Station and analyzed by ion chromatography for Cl-, SO4-, and NO3-. Atomic absorption spectroscopy was used to analyze samples for Ca2+, Na+, K+, Mg2+, and by Latchet for NH4+ in the Arikaree Lab at the University of Colorado Boulder. Samples were analyzed for water isotopes using cavity ring-down spectroscopy on a Picarro in the Barnard Lab at the University of Colorado Boulder.
Contributing areas to each sampling point were calculated using a MD-Infinity flow routing algorithm on a sink-filled 1 m lidar-derived DEM.
Funding for these data was provided by the National Science Foundation Grant #OPP-1637708 for Long Term Ecological Research.