Caroline C Clason

Durham University | DU · Department of Geography

Meltwater drainage through ice sheets has recently been a key focus of glaciological research due to its influence on the dynamics of ice sheets in a warming climate. However, the processes, topologies and products of ice sheet hydrology are some of the least understood components of both past and modern ice sheets. This is to some extent a result...

Meltwater delivered to the bed of the Greenland Ice Sheet is a driver of variable ice-motion through changes in effective pressure and enhanced basal lubrication. Ice surface velocities have been shown to respond rapidly both to meltwater production at the surface and to drainage of supraglacial lakes, suggesting efficient transfer of meltwater fro...

New high resolution multibeam data in the Gulf of Bothnia reveal for the first time the subglacial environment of a Bothnian Sea Ice Stream. The geomorphological record suggests that increased meltwater production may have been important in driving rapid retreat of Bothnian Sea ice during deglaciation. Here we apply a well-established one-dimension...

Over 11 000 L of kerosene was deposited on the surface of Rabots glaciär on the Kebnekaise Massif, northern Sweden, following the crash of a Royal Norwegian Air Force aircraft in March 2012. An environmental monitoring programme was subsequently commissioned, including a series of dye tracing experiments during the 2013 melt season, conducted to in...

The transfer of surface-generated meltwater to the subglacial drainage system through full ice thickness crevassing may lead to accelerated glacier velocities, with implications for ice motion under future climatic scenarios. Accurate predictions of where surface meltwater accesses the ice/bed interface are therefore needed in fully coupled hydrody...

Fine sediment plays an important role in the healthy functioning of river ecosystems providing nutrients and contributing to habitat functioning. However, excessive sediment supply into rivers has several detrimental impacts on water quality and it causes sedimentation in river channels, reservoirs and estuaries. In addition, silts and clays are ge...

Mountain glaciers are crucial sources of fresh water, contributing directly and indirectly to water, energy and food supplies for hundreds of millions of people. Assessing the impact of diminishing glacial meltwater contributions to the security of this resource is critical as we seek to manage and adapt to changing freshwater dynamics in a warming...

Spatially variable basal conditions are thought to govern how ice sheets behave at glacial time scales (>1000 years) and responsible for changes in dynamics between the core and peripheral regions of the Laurentide and Fennoscandian ice sheets. Basal motion is accomplished via the deformation of unconsolidated sediments, or via sliding of the ice o...

Anthropogenic contamination has been detected in glacial and proglacial environments around the globe. Through mechanisms of secondary release, these contaminants are finding their way into glacial hydrological systems and downstream environments, with potential to impact hundreds of millions of people who rely on glacial meltwater for water, food...

Riverine sediments play an important role in the healthy functioning of river ecosystems as they provide nutrients and a connectivity signal throughout the catchment sediment cascade. However, excess sediment supply to rivers can have several detrimental impacts on water quality, availability and ecology. The application of catchment management pra...

Increasing pressures on ecosystems in the Latin American region, as well as the adoption of multilateral conservation commitments, have led to the implementation of instruments that are economic in nature but oriented towards the recovery, conservation, and functioning of ecosystems such as Payment for Ecosystem Services (PES). In the Peruvian Ande...

Historically, glaciers have been seen as pristine environments. However, recent research has shown that glaciers can accumulate and store contaminants over long timescales, through processes such as atmospheric deposition, sedimentation, glacial hydrology and mass movements. Studies have identified numerous anthropogenically derived contaminants wi...

The release of legacy contaminants such as fallout radionuclides (FRNs) in response to glacier retreat is a process that has received relatively little attention to date, yet may have consequences as a source of secondary contamination as glaciers melt and down-waste in response to a warming climate. The presence of FRNs in glacier-fed catchments i...

Spatially variable bed conditions govern how ice sheets behave at glacial time scales (>1000 years). The presence or lack of complete sediment cover is responsible for changes in dynamics between the core and peripheral regions of the Laurentide and Fennoscandian ice sheets. A key component of this change is because sliding is promoted when unconso...

The release of legacy fallout radionuclides (FRNs) in response to glacier retreat is a process that has received relatively little attention to date, yet may have important consequences as a source of secondary contamination as glaciers melt and down-waste in response to a warming climate. The prevalence of FRNs in glacier-fed catchments is poorly...

Cryoconite, a sediment found on the surface of glaciers, is known for its ability to accumulate radionuclides. New data on cryoconite from the Morteratsch glacier (Switzerland) are presented to shed light on the mechanisms that control the distribution of radioactivity in cryoconite. Among the radionuclides detected in our samples, we have identifi...

Cryoconite is rich in natural and artificial radioactivity, but a discussion about its ability to accumulate radionuclides is lacking. A characterization of cryoconite from two Alpine glaciers is presented here. Results confirm that cryoconite is significantly more radioactive than the matrices usually adopted for the environmental monitoring of ra...

Cryoconite, a sediment found on the surface of glaciers, is known for its ability to accumulate radionuclides. New data on cryoconite from the Morteratsch glacier (Switzerland) are presented with the aim to shed light on the mechanisms that control the distribution of radioactivity in cryoconite. Among the many radionuclides detected in our samples...

Cryoconite is extremely rich in natural and artificial radionuclides, but a comprehensive discussion about its ability to accumulate radioactivity is lacking. A characterization of cryoconite from two Alpine glaciers is presented and discussed. Results confirm that cryoconite is among the most radioactive environmental matrices, with activity conce...

Relict landforms provide a wealth of information on the evolution of the modern landscape and climate change in the past. To improve understanding of the origin and development of these landforms we need better spatial measurements across a variety of scales. This can be challenging using conventional surveying techniques due to difficulties in lan...

Ice-stream dynamics are strongly controlled by processes taking place at the ice/bed interface where subglacial water both lubricates the base and saturates any existing, underlying sediment. Large parts of the former Eurasian ice sheet were underlain by thick sequences of soft, marine sediments and many areas are imprinted with geomorphological fe...

The Gulf of Bothnia hosted a variety of palaeo-glaciodynamic environments throughout the growth and decay of the last Fennoscandian Ice Sheet, from the main ice-sheet divide to a major corridor of marine- and lacustrine-based deglaciation. Ice streaming through the Bothnian and Baltic basins has been widely assumed, and the damming and drainage of...

Supraglacial lake drainage events are common on the Greenland Ice Sheet. Observations on the west coast typically show an up-glacier progression of drainage as the annual melt extent spreads inland. We use a suite of remote sensing and modelling techniques in order to study a series of lakes and water-filled crevasses within 20km of the terminus of...

Geomorphological mapping from the new LiDAR (Light Detection and Ranging)-derived digital elevation model for Sweden and a high-resolution multibeam bathymetry data-set for the Gulf of Bothnia reveals a continuous system of glacial landforms crossing the transition between the modern terrestrial and marine environments. A palaeo-ice stream in the n...

Over 11 000 L of hydrocarbon pollution was deposited on the surface of Rabots glaciär on the Kebnekaise Massif, northern Sweden, following the crash of a Royal Norwegian Air Force aircraft in March 2012. An environmental monitoring programme was subsequently commissioned, including water, snow and ice sampling. The scientific programme further incl...

Meltwater delivered to the bed of the Greenland Ice Sheet is a driver of variable ice-motion through changes in effective pressure and enhanced basal lubrication. Ice surface velocities have been shown to respond rapidly both to meltwater production at the surface and to drainage of supraglacial lakes, suggesting efficient transfer of meltwater fro...

We simulated the LateWeichselian extent and dynamics of the Eurasian ice sheets using the shallow-ice approximation ice-sheet model SICOPOLIS. Our simulated Last Glacial Maximum ice-sheet extents closely resemble geomorphological reconstructions, and areas of modelled fast flow are consistent with the known locations of palaeo-ice streams. Motivate...

On March 15th 2012 a Royal Norwegian Air Force Lockheed Martin C-130J Super Hercules aircraft crashed into the western face of Kebnekaise in northern Sweden, approximately 50 m below the mountain ridge, during a military exercise. It was carrying c.14000 l of kerosene jet fuel when it left Narvik, and an estimated minimum of 8 m3 of fuel was deposi...

The influence of seasonal influx of supraglacial meltwater on basal water pressures and consequent changes in ice surface velocity has been a focus of research spanning over three decades, particularly focussing on alpine glaciers. Now, with increased recognition for a need to better include glacial hydrology within models of ice dynamics and ice s...

The transfer of surface-generated meltwater to the subglacial drainage system through full ice thickness crevassing may lead to accelerated glacier velocities, with implications for ice motion under future climatic scenarios. Accurate predictions of where surface meltwater accesses the ice/bed interface are therefore needed in fully coupled hydrody...

Dynamic response to increased supraglacial meltwater generation and subsequent influx to the subglacial hydrological system is well documented in temperate glaciers. Meltwater-enhanced acceleration of ice surface velocities, or ‘spring events’, have also more recently been observed on polythermal glaciers and outlet glaciers of the Greenland Ice Sh...

Recent studies have shown that Greenland outlet glacier velocities may be responding to increased meltwater generation (Shepherd et al, 2009; Zwally et al, 2002). Where sufficient supraglacial meltwater is routed into crevasses and moulins it could act to lubricate the bed, resulting in dynamic thinning and accelerated transfer of ice mass to glaci...