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Geophysical constraints on the dynamics and retreat of the Barents Sea ice sheet as a palaeobenchmark for models of marine icesheet deglaciation
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-11-14)
Our understanding of processes relating to the retreat of marine-based ice sheets, such as the West Antarctic Ice Sheet and tidewater-terminating glaciers in Greenland today, is still limited. In particular, the role of ice-stream instabilities and oceanographic dynamics in driving their collapse are poorly constrained beyond observational timescales. Over numerous glaciations during the Quaternary, ...
Biocryomorphology: integrating microbial processes with ice surface hydrology, topography and roughness
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-12-02)
UAV photogrammetry and structure from motion to assess calving dynamics at Store Glacier, a large outlet draining the Greenland ice sheet
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-01-06)
This study presents the application of a costeffective, unmanned aerial vehicle (UAV) to investigate calving dynamics at a major marine-terminating outlet glacier draining the western sector of the Greenland ice sheet. The UAV was flown over Store Glacier on three sorties during summer 2013 and acquired over 2000 overlapping, geotagged images of the calving front at an ∼ 40 cm ground sampling ...
Changing surface–atmosphere energy exchange and refreezing capacity of the lower accumulation area, West Greenland
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-11-18)
We present 5 years (2009–2013) of automatic weather station measurements from the lower accumulation area (1840 m a.s.l. – above sea level) of the Greenland ice sheet in the Kangerlussuaq region. Here, the summers of 2010 and 2012 were both exceptionally warm, but only 2012 resulted in a strongly negative surface mass budget (SMB) and surface meltwater run-off. The observed run-off was ...
Derivation of High Spatial Resolution Albedo from UAV Digital Imagery: Application over the Greenland Ice Sheet
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-05-23)
Measurements of albedo are a prerequisite for modeling surface melt across the Earth’s cryosphere, yet available satellite products are limited in spatial and/or temporal resolution. Here, we present a practical methodology to obtain centimeter resolution albedo products with accuracies of ±5% using consumer-grade digital camera and unmanned aerial vehicle (UAV) technologies. Our method comprises ...
Direct measurements of meltwater runoff on the Greenland ice sheet surface
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-12-05)
Meltwater runoff from the Greenland ice sheet surface influences surface mass balance (SMB), ice dynamics, and global sea level rise, but is estimated with climate models and thus difficult to validate. We present a way to measure ice surface runoff directly, from hourly in situ supraglacial river discharge measurements and simultaneous high-resolution satellite/drone remote sensing of upstream ...
Deglaciation of the Eurasian ice sheet complex
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-06-14)
The Eurasian ice sheet complex (EISC) was the third largest ice mass during the Last Glacial Maximum with a span of over 4500 km and responsible for around 20 m of eustatic sea-level lowering. Whilst recent terrestrial and marine empirical insights have improved understanding of the chronology, pattern and rates of retreat of this vast ice sheet, a concerted attempt to model the deglaciation of the ...
Area and volume of mid-latitude glacier-like forms on Mars
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-12-04)
Although a substantial ice cover has been identified within the mid-latitudes of Mars, there is uncertainty regarding the formation, current and former volume, and dynamic evolution of these ice masses. Here, we present the first comprehensive ice volume estimate of martian glacier-like forms (GLFs) from systematic population scale mapping and volumetric analysis. The outlines of 1243 GLFs were ...
Rock glaciers in central Patagonia
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-10-22)
Active rock glaciers are ice and debris-cored landforms common in cold arid mountains. They have not been widely described in the Patagonian Andes of southern South America and here we provide the first rock glacier inventory for the Jeinimeni region to the east of the contemporary North Patagonian Icefield. Detailed analysis of available satellite imagery and fieldwork demonstrates the presence of ...
A Full-Stokes 3-D Calving Model Applied to a Large Greenlandic Glacier
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-01-30)
Iceberg calving accounts for around half of all mass loss from both the Greenland and Antarctic ice sheets. The diverse nature of calving and its complex links to both internal dynamics and climate make it challenging to incorporate into models of glaciers and ice sheets. Here we present results from a new open‐source 3‐D full‐Stokes calving model developed in Elmer/Ice. The calving model implements ...