Automatic weather stations for basic and applied glaciological research

Since the early 1980s, the Geological Survey of Denmark and Greenland (GEUS) glaciology group has developed automatic weather stations (AWSs) and operated them on the Greenland ice sheet and on local glaciers to support glaciological research and monitoring projects (e.g. Olesen & Braithwaite 1989; Ahlstrøm et al. 2008). GEUS has also operated AWSs in connection with consultancy services in relation to mining and hydropower pre-feasibility studies (Colgan et al. 2015). Over the years, the design of the AWS has evolved, partly due to technological advances and partly due to lessons learned in the field. At the same time, we have kept the initial goal in focus: long-term, year-round accurate recording of ice ablation, snow depth and the physical parameters that determine the energy budget of glacierised surfaces. GEUS has an extensive record operating AWSs in the harsh Arctic environment of the diverse ablation areas of the Greenland ice sheet, glaciers and ice caps (Fig. 1). The current GEUS-type AWS (Fig. 2) records meteorological, surface and sub-surface variables, including accumulation and ablation, as well as for example ice velocity. A large part of the data is transmitted by satellite near real-time to support ongoing applications, field activities and the planning of maintenance visits. The data have been essential for assessing the impact of climate change on land ice. The data are also crucial for calibration and validation of satellite-based observations and climate models (van As et al. 2014).