Expedition Name (& Club): Svalbard 2018 - Austre Broggerbreen

Destination country: Norway
Region: Austre Broggerbreen, Broggerhalvoya Peninsula, Svalbard

Lat: 78.9100 Long: 11.8114 Elevation: 114 m
MEF funding: none

Leader: Ms Jayne Kamintzis

Brief Expedition objectives:

List a short summary of the main Expedition objectives.

The objective of the expedition is to conduct a repeat cave survey of the main ice channel transporting water out of the Austre Broggerbreen glacier system, using Terrestrial Laser Scanning (TLS) to recreate the channel interior in three-dimensions. This englacial channel was previously surveyed in March 2017 by the intended 2018 expedition team, with this second survey being proposed in order to determine the nature and rate of channel change after a single melt season.

How can the GPF support your Expedition?:

Please explain the aspects of the trip which make it eligible for Ghar Parau funding.

This expedition is eligible for GPF for several reasons:
- The project uses innovative and novel TLS techniques for the scientific study of an ice cave in the remote Svalbard region, to reveal its interior geometry in greater detail than that afforded by traditional surveying techniques, providing mm-cm scale mapping.
- Successful mapping of the cave by team members in 2017 provides preparatory work and research, meaning that the team has prior knowledge of the cave's accessibility and experience operating within this area. Furthermore, the applicant has financially managed 2 field seasons to this region, including the 2017 research trip.
- Research conducted will form a major part of the PhD applicant's doctoral thesis, and will form the basis of journal paper outputs.

Any grant aid will be extremely beneficial to the project, allowing for its conduction, as there is insufficient funding awarded to the PhD student to support a return trip, in order to conduct a repeat survey.

Detailed description of objectives:

Give a more detailed account of the purpose of the trip, including any particular known caves you intend to visit, specific areas where you will explore for new cave, and scientific experiments you will attempt.

Meltwater channels within glacier ice are relatively inaccessible, meaning that direct observations and measurements of such channels are limited and, thus, little is known about their evolution over time. As this delivery of meltwater to the interior and base of ice masses influences glacier mass balance, as a result of its close association with ice dynamics, it is crucial to enhance scientific understanding of the ways in which water is routed through a glacier.

Therefore, the main objective of the expedition is to provide a second laser scan survey of the main englacial channel delivering water to the glacier forefield, in order to determine the nature, and quantify the rate, of channel change between the March 2017 and March 2018 surveys. This will identify how the ice channel changes over the course of one summer melt season.

To achieve this, the main field objectives of the expedition are:

- To conduct full laser scans of the main englacial meltwater channel exiting the glacier, to reconstruct the channel interior in 3D.
- To identify structural glaciological features within the channel, in terms of fractures, faults and debris.
- To conduct traditional cave surveying techniques of the channel to serve as complementary and contingency data.

The data collected will be fully processed and analysed upon return to the UK, to provide detailed maps of the interior geometry of the channel, including planform, cross-section and longitudinal profiles. The processed point clouds produced by the laser scanner, and the aforementioned maps will be compared to the 2017 surveys, to identify areas of morphological change. This will enable quantification of this change in three-dimensions, to reveal the rate at which this englacial channel has changed over an annual timescale, something not previously achieved.

Previous work in this area:

Give details of any previous work in this area by your own and other teams. Include references to reports and articles published on the area, and the names of any local cavers or academics with whom you have discussed the Expedition.

There have been several studies into the englacial hydrological system of Austre Broggerbreen, using a variety of geophysical, dye tracing and glacio-speleological techniques. This research has given an insight into the changes in meltwater chemistry as the glacier thermal regime has changed from a polythermal to a cold-based one, as well as providing evidence of water flow through the ice from different surface inputs to the main portal of the glacier.
Several moulins on the glacier provide accessible entry points for the conduction of speleological investigation. Research by Vatne and others has focused on the geometry and morphology of englacial conduits, exploring the differences between such channels, the features found within them that reflect/influence water flow, and the formation of such features. Furthermore, Stuart et al (2003) used ground penetrating radar (GPR) techniques to survey the length of the englacial channel leading to the portal, which is the channel to be studied by this expedition. This study found that the channel links to a large moulin situated in the lower ablation zone of the glacier, and mapped the length using the results of the GPR study and direct observations made close to the moulin.

More specifically, the ice channel intended for surveying on this expedition was explored and mapped using a laser scanner in March 2017, by the principal investigator and the proposed personnel for the intended 2018 survey, Catrin Thomas. This research demonstrates the accessibility of the channel entrance, which is at ground level and allows easy walking entry and maneuverability. The channel was scanned from the entrance to ~ 300 m upstream, with detailed notes being made on the glaciological structure and morphology.

KEY PUBLICATIONS

Stuart G (2003) Characterization of englacial channels by ground-penetrating radar: An example from austre Brøggerbreen, Svalbard. Journal of Geophysical Research, 108(B11). (doi:10.1029/2003jb002435)

Vatne G (2001) Geometry of englacial water conduits, Austre Brøggerbreen, Svalbard. Norsk Geografisk Tidsskrift - Norwegian Journal of Geography, 55(2), 85-93. (doi:10.1080/713786833)

Vatne G and Irvine-Fynn TDL (2016) Morphological dynamics of an englacial channel. Hydrology and Earth System Sciences, 20(7), 2947-2964. (doi:10.5194/hess-20-2947-2016)

Vatne G and Refsnes I (2003) Channel pattern and geometry of englacial conduits. 6th International Symposium 'Glacier caves and karst in Polar Regions', Ny-Ålesund, Svalbard, 181-188.