ALE has supported a variety of projects by the Centro de Estudios Científicos (Center for Scientific Studies, Valdivia, Chile), including involvement in the Lake Ellsworth Project, investigation of sub-glacial lake CECs, glacier flow rate and bedrock studies at Union Glacier, and several oversnow traverses. CECs have been invaluable in undertaking GPR surveys of the Patriot Hills to Union Glacier route and of Union Glacier itself. They have worked closely with ALE commissioned land surveyors to make surveys of Union Glacier ice runway.
2004 South Pole Traverse
CECs first accompanied the Chilean Army traverse to the South Pole in 2004 and subsequently surveyed routes from Patriot Hills to Lake Ellsworth and from Union Glacier to Lake Ellsworth drilling site. ALE provided tractor, with driver/mechanics and fuel for all traverses, as well as meals and accommodation at Union Glacier Camp. Current work is focused on the stability of the West Antarctic Ice Sheet (WAIS) and investigation of newly discovered subglacial lake CECs.
Stability of the West Antarctic Ice Sheet
In January 2014, CECs conducted an oversnow traverse to the triple ice divide between Pine Island, Institute and Rutford ice streams in the WAIS. The traverse convoy was comprised of a scientific and a logistics module installed on Lehmann sledges and pulled by a Prinoth tractor provided by ALE. In total, the traverse covered near 1100 km (685 miles) from their base camp at Union Glacier. (79.8ºS/83.4ºW).
The main aim of the campaign was to map the surface and subglacial topography of the region, as well as to identify the internal structure of the ice, and the surface mass balance and ice dynamics. Two different radars operated on a synchronized basis during the long term traverse and the radar data was geolocated using GPS receivers. A network of stakes was installed for mass balance and ice dynamic purposes. A couple of shallow snow/firn cores were also collected.
The West Antarctic Icesheet (WAIS) has been considered potentially unstable, especially Pine Island Glacier, which is the most dynamic in the region and may be experiencing irreversible changes. Little is known about the present and past dynamics at its ice divide with nearby ice streams. Is the ice divide experiencing a migration in response to the lower thinning and ongoing acceleration? Is there evidence within the internal structure of the ice of past dynamic changes? The researchers hope that their data will help answer these questions.
Early indications of a subglacial lake were detected during the initial traverse and the team returned the following season to complete an exhaustive mapping of the area. The results were published in the specialized journal “Geophysical Research Letters” in May 2015.
Subglacial Lake CECs
CECs researchers conducted fieldwork from ALE-supported field camp at subglacial lake CECs (SLCECs) in January 2016. They conducted geophysical measurements on the subglacial lake; re-measured the GPS positions of a network of beacons installed in the last two years; and took ice thickness measurements in sectors bordering SLCECs. They also conducted mass balance and weather measurements, including the installation of a solar and wind-powered automatic weather station with a real-time transmission.
Fieldwork continued in December 2016, with detailed studies of the depth of SLCECs; the presence of sediment in its basin; and the surrounding subglacial features. The team traveled by ALE-supported tractor-train, from Union Glacier to SLCECs, where they set up their field camp and mobile research station. They were joined by two researchers from the British Antarctic Survey (BAS), who worked with the CECs crew to take GPS and seismic measures. A detailed account of their expedition and fieldwork can be found in their expedition blog.
http://www.cecs.cl/website/index.php/en/menu-noticias/1151-expedicion-antartica-2016 (Dec 2016 expedition blog)