A5024870976- Cryospheric studies and observations
- Methane Hydrates and Related Phenomena
- Polar Research and Ecology
- Geology and Paleoclimatology Research
- Climate change and permafrost
- Atmospheric and Environmental Gas Dynamics
- Microbial Community Ecology and Physiology
- Arctic and Antarctic ice dynamics
- Pleistocene-Era Hominins and Archaeology
- Winter Sports Injuries and Performance
- Mercury impact and mitigation studies
- Per- and polyfluoroalkyl substances research
- Planetary Science and Exploration
- Analytical Chemistry and Sensors
- Soil Management and Crop Yield
- Geological Studies and Exploration
- Marine animal studies overview
- Smart Materials for Construction
- Geomagnetism and Paleomagnetism Studies
- Paleontology and Stratigraphy of Fossils
- Hydrocarbon exploration and reservoir analysis
- Silicon Effects in Agriculture
- Indigenous Studies and Ecology
- Soil Carbon and Nitrogen Dynamics
- Ocean Acidification Effects and Responses
UiT The Arctic University of Norway
2022-2024
University of Bristol
2015-2024
Centre for Arctic Gas Hydrate, Environment and Climate
2022
McGill University
2013-2018
Abstract The Greenland Ice Sheet is currently not accounted for in Arctic mercury budgets, despite large and increasing annual runoff to the ocean socio-economic concerns of high levels organisms. Here we present concentrations meltwaters from three glacial catchments on southwestern margin evaluate export downstream fjords based samples collected during summer ablation seasons. We show that dissolved are among highest recorded natural waters yields these (521–3,300 mmol km −2 year −1 ) two...
The Lost Hammer (LH) Spring is the coldest and saltiest terrestrial spring discovered to date characterized by perennial discharges at subzero temperatures (-5°C), hypersalinity (salinity, 24%), reducing (≈-165 mV), microoxic, oligotrophic conditions. It rich in sulfates (10.0%, wt/wt), dissolved H2S/sulfides (up 25 ppm), ammonia (≈381 μM), methane (11.1 g day(-1)). To determine its total functional genetic potential identify active microbial components, we performed metagenomic analyses of...
We report the first in situ high-resolution nitrate time series from two proglacial meltwater rivers draining Greenland Ice Sheet, using a recently developed submersible analyzer based on lab-on-chip (LOC) technology. The low sample volume (320 μL) required by LOC meant that concentration (few micromolar to submicromolar), highly turbid subglacial could be filtered and colorimetrically analyzed situ. Nitrate concentrations Leverett Glacier southwest Kiattuut Sermiat southern exhibited clear...
Abstract Surface melt from the Greenland Ice Sheet (GrIS) collects particulate organic carbon (POC) as it drains into subglacial environments and transports downstream where serves a microbial substrate. We hypothesized that older POC is entrained by meltwaters drainage network expands upglacier over summer. To test this, samples were collected meltwater river exiting GrIS an ablation season 14 C dated. Resulting values compared with hydrochemistry satellite observations of catchment area....
Abstract Globally averaged riverine silicon (Si) concentrations and isotope composition (δ 30 Si) may be affected by the expansion retreat of large ice sheets during glacial−interglacial cycles. Here we provide evidence this based on δ Si meltwater runoff from a Greenland Ice Sheet catchment. Glacier has lightest measured in running waters (−0.25 ± 0.12‰), significantly lower than nonglacial rivers (1.25 0.68‰), such that overall decline glacial since Last Glacial Maximum (LGM) explain...
Meltwater streams connect the glacial cryosphere with downstream ecosystems. Dissolved and particulate matter exported from ecosystems originates contrasting supraglacial subglacial environments, microbial cells have potential to serve as ecological hydrological indicators for ecosystem processes. Here, we compare assemblages meltwater of 24 glaciers six (sub)Arctic regions - southwestern Greenland Ice Sheet, Qeqertarsuaq (Disko Island) in west Greenland, Iceland, Svalbard, western Norway,...
Microbes transported by glacial meltwater streams are thought to be a product of passive dispersal from both supra- and subglacial sources, though studies investigating the origins these assemblages scarce. Here, we conducted survey within large catchment containing multiple glaciers on Qeqertarsuaq (Disko Island), west Greenland, investigate whether meltwater-exported microbial in suspended sediments differ between streams, if they reflect corresponding bulk extraglacial sediment...
Glacial meltwater drains into proglacial rivers where it interacts with the surrounding landscape, collecting microbial cells as travels downstream. Characterizing composition of resulting assemblages in transport can inform us about intra-annual changes flowpaths beneath glacier well hydrological connectivity areas. Here, we investigated how structure suspended evolves over course a melt season for three catchments Greenland Ice Sheet (GrIS), reasoning that differences size and proportion...
Abstract Measuring pH in glacial meltwaters is challenging, because they are cold, remote, subject to freeze‐thaw cycles and have low ionic strength. Traditional methods often perform poorly there; glass electrodes high drift long response times, spectrophotometric techniques unpractical remote environments. Ion selective field effect transistor (ISFET) sensors a promising alternative, proven marine industrial applications. We assess the suitability of two models ISFET, Honeywell Durafet...
Abstract. The Arctic is one of the most rapidly warming regions Earth, with predicted temperature increases 5–7 ∘C and accompanying extensive retreat glacial systems by 2100. Retreating glaciers will reveal new land surfaces for microbial colonisation, ultimately succeeding to tundra over decades centuries. An unexplored dimension these changes impact upon emission consumption halogenated organic compounds (halocarbons). Halocarbons are involved in several important atmospheric processes,...
Recent studies have shown the release of methane (CH4) from melting Greenland Ice Sheet (GrIS) and identified it as having an additional potential positive climate feedback. This originates mainly acetoclastic methanogenesis in subglacial sediments, accumulates over time, subsequently diffuses into hydrologic network which transports to ice sheet margin. The rates production emission GrIS sediments likely depend on a number factors, including sediment depth distribution, organic matter...
Abstract. The microbial ecosystems that lie beneath ice sheets can impact and contribute to global biogeochemical cycles, yet remain poorly understood given the logistical challenges in directly accessing subglacial environment. Studies instead often rely on indirect sampling of systems via collection meltwaters emerging from margins. However, origin exported material these waters will change over a melt season as glacier hydrology responds changes surface melt. Here, we reveal trends...
Recent research underscores a potential, yet overlooked, positive climate feedback mechanism: the transport of subglacially produced methane (CH4) to atmosphere via meltwater. While majority focused on release from beneath Greenland Ice Sheet, mountain glaciers have been largely understudied, creating gap in our understanding spatial distribution subglacial CH4 emissions. Emerging Iceland, Canada, Alaska, and China suggests presence also other than Sheet.   Here, we explore...
Abstract Ice sheets overlay active and putatively widespread microbial ecosystems. An subglacial biota has the potential to impact strongly on (bio)geochemistry of local as well downstream environments. Such impacts partly depend distribution populations, types habitats present beneath ice, their connectivity. In ablation zone Greenland Sheet (GrIS), supraglacial meltwaters are routed ice-sheet bed during melt season, flushing out waters, sediments, cells proglacial environments via runoff....