Abstract:
To understand the drivers and consequences of climate change on timescales important to humans, the paleoclimate of ice cores, the glacial system and local climate patterns were analysed from the Evans Piedmont Glacier. The Evans Piedmont Glacier was explored using GPS and GPR surveys and snow profile properties. GPR measurements were made with low and high frequency radar pulses to map the
... bedrock interface and internal flow structures in the glacier. Snow pits were excavated and the snow profile was analysed with 1cm resolution for snow chemistry and isotopic composition, dust content and mineralogy. Density and temperature of the snow pack was measured with 5cm resolution and snow crystal structure was investigated. One snow profile was sampled at 1cm resolution using ultra clean snow sampling methodology in order to maximise the array of potential measurable trace elements. Isotopic and major ion composition was also measured. Density and temperature profiling were conducted at 5cm resolution once sampling was complete. Physical description notes of crystal structure and the location of hoar horizons were used to provide a preliminary chronology. Two snow precipitation events were sampled hourly throughout the snowfall and was analysed for snow chemistry and isotopic composition. A 180m core was extracted, measured and logged. Each 1m long core had its core temperature measured (within 5 mins of core recovery), weighed to calculate density and determine the depth of bubble close off and firn/ice transition and investigated for crystal structure, melt and dust/tephra layer occurrence. Analysis of volume, grain size and mineralogy was taken to determine the source and to infer wind pattern and strength. Small chips were used to study gas bubble properties (including porosity, gas bubble size and geometry). The borehole was measured for temperature and light penetrations after drilling. Two snow profiles were analysed with high (1cm) resolution for analysis on snow chemistry and isotopic composition, dust content and mineralogy. Three snow pits were excavated to measure density and temperature of the snow pack and to study snow crystal structure and their geographic variability. An automatic weather station was installed as of 15 Nov, 2004 measuring air temperature, dew point temperature and solar radiation (incoming) at 2.5m height, snow accumulation and air temperature at 1.5m height, snow temperature from 0.5-2.5m depth at 12cm intervals and barometric pressure, wind speed and direction. Snow accumulation sensor and high precision snow temperature probe were installed to monitor snow accumulation rates, the potential influence of snow loss through sublimation, wind erosion or melt and the quality of preservation of the meteorological signal in the snow. Mass balance measurements using high precision, differential, static GPS to quantify total accumulation or ablation of the glacier were installed (coffee can devices), marked by GPS and measured in subsequent seasons.