High-Endurance UAV for Monitoring Calving Glaciers: Application to the Inglefield Bredning and Eqip Sermia, Greenland

Abstract

Unmanned aerial vehicle (UAV) photogrammetry has become an important tool for generating multi-temporal, high-resolution ortho-images and digital elevation models (DEMs) to study glaciers and their dynamics. In polar regions, the roughness of the terrain, strong katabatic winds, unreliability of compass readings, and inaccessibility due to lack of infrastructure pose unique challenges for UAV surveying. To overcome these issues, we developed an open-source, low-cost, high-endurance, fixed-wing UAV equipped with GPS post-processed kinematic for the monitoring of ice dynamics and calving activity at several remote tidewater glaciers located in Greenland. Our custom-built UAV is capable of flying for up to 3 h or 180 km and is able to produce high spatial resolution (0.25-0.5 m per pixel), accurately geo-referenced (1-2 pixels) ortho-images and DEMs. We used our UAV to perform repeat surveys of six calving glacier termini in north-west in July 2017 and of Eqip Sermia glacier, west Greenland, in July 2018. The endurance of our UAV enabled us to map the termini of up to four tidewater glaciers in one flight and to infer the displacement and calving activity of Eqip Sermia at short (105 min) timescale. Our study sheds light on the potential of long-range UAVs for continuously monitoring marine-terminating glaciers, enabling short-term processes, such as the tidal effects on the ice dynamics, short-lived speed-up events, and the ice fracturing responsible for calving to be investigated at unprecedented resolution.

Challenges in predicting Greenland supraglacial lake drainages at the regional scale

“…1, the MEaSUREs maps contain a handful of gaps: winters 2010/2011, 2011/2012, 2013/2014, and 2017/2018. To fill the 2013/2014 gap, we used a dataset from the European Space Agency Climate Change Initiative (Boncori et al, 2018;Khvorostovsky et al, 2016). Veloci-Figure 1.…”

“…This mission gathered topography data; data from repeat flights over the same area could be used to generate velocity and strain-rate maps, following Chudley et al (2020). In fact, Jouvet et al (2019) performed eight surveys of glacier termini by a custom-built 2 m UAV to produce a time series of velocity maps over a 12 d period in July. These velocities compared to satellite-derived velocities to within ∼ 10 %.…”

“…These velocities compared to satellite-derived velocities to within ∼ 10 %. Operation of longer-range, fixed-wing UAVs such as the Manta typically requires more personnel than local-range UAVs, including ground-control and remote-control pilots and engineers (Crocker et al, 2012), but UAVs with lower operational costs are being developed (e.g., Jouvet et al, 2019). Overall, the success of UAV photogrammetry in monitoring regional-scale strain rates hinges on the magnitude of support: adequate temporal and spatial coverage will rely on longer field seasons with larger crews than are typically granted to field-based scientific studies.…”

UAV-Based Photogrammetry and LiDAR for the Characterization of Ice Morphology Evolution

“…Alternatively, no GCPs geo-referencing approaches begin to emerge when conditions are limited [10], [31]. For multi-temporal studies, it is a common practice to measure the shifts of two bedrock areas on each side of the glaciers between multiple surveying products as the uncertainty of DEM differentiation [32]. In this paper, based on the orthomosaics and elevation models from the two UAV technologies, we make full use of the well-established DEM of Difference (DoD) methodology [33] to unravel and quantify the evolution of ice morphology.…”

In situ measurements of the ice flow motion at Eqip Sermia Glacier using a remotely controlled unmanned aerial vehicle (UAV)

“…Among them, marine-terminating glaciers usually show fast ice flow (up to several meters per day or even faster) due to buoyant forces with variations at different timescales (e.g., Bartholomew et al, 2012). These range from minute-scale ice flow responses to the collapse of large icebergs (e.g., Murray et al, 2015), to tidally driven hourly-scale variations (e.g., Sugiyama et al, 2015), to daily-scale ice speed-ups induced by rapid change in the subglacial hydrological system (Jouvet et al, 2018), e.g., due to the sudden drainage of a supraglacial lake (Kjeldsen et al, 2014). To continuously capture the dynamics of marine-terminating glaciers, it is therefore necessary to develop methods that can measure their ice flow in high spatial and temporal resolution.…”