A5004121654- Arctic and Antarctic ice dynamics
- Methane Hydrates and Related Phenomena
- Oceanographic and Atmospheric Processes
- Geological Studies and Exploration
- Cryospheric studies and observations
- Marine and environmental studies
- Marine and coastal ecosystems
- Climate change and permafrost
- Geology and Paleoclimatology Research
- Climate variability and models
- Atmospheric and Environmental Gas Dynamics
- Arctic and Russian Policy Studies
- Food Industry and Aquatic Biology
- Winter Sports Injuries and Performance
- Polar Research and Ecology
- Aquatic and Environmental Studies
- Maritime Navigation and Safety
- Geological formations and processes
- Marine and fisheries research
- Maritime Transport Emissions and Efficiency
- Offshore Engineering and Technologies
- Greenhouse Technology and Climate Control
- Geographic Information Systems Studies
- Ocean Waves and Remote Sensing
- Geochemistry and Elemental Analysis
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung
2016-2025
Australian Wool Innovation (Australia)
2023
Bangor University
2020
University of Alaska Fairbanks
2009-2014
NOAA National Marine Fisheries Service
2011
NOAA National Marine Fisheries Service Alaska Fisheries Science Center
2011
Arctic Ocean properties and processes are highly relevant to the regional global coupled climate system, yet still scarcely observed, especially in winter. Team OCEAN conducted a full year of physical oceanography observations as part Multidisciplinary drifting Observatory for Study Climate (MOSAiC), drift with sea ice from October 2019 September 2020. An international team designed implemented program characterize system unprecedented detail, seafloor air-sea ice-ocean interface,...
Enhanced warm, salty subarctic inflows drive high-latitude atlantification, which weakens oceanic stratification, amplifies heat fluxes, and reduces sea ice. In this work, we show that the atmospheric Arctic Dipole (AD) associated with anticyclonic winds over North America cyclonic Eurasia modulates from Atlantic across Nordic Seas. The alternating AD phases create a "switchgear mechanism." From 2007 to 2021, switchgear mechanism weakened northward enhanced sea-ice export Fram Strait...
Concern about impacts of climate change in the Bering Sea prompted several research programs to elucidate mechanistic links between and ecosystem responses. Following a detailed literature review, Hunt et al. (2011) (Deep-Sea Res. II, 49, 2002, 5821) developed conceptual framework, Oscillating Control Hypothesis (OCH), linking climate-related changes physical oceanographic conditions stock recruitment using walleye pollock (Theragra chalcogramma) as model. The OCH model treats zooplankton...
Abstract A 15-yr duration record of mooring observations from the eastern (>70°E) Eurasian Basin (EB) Arctic Ocean is used to show and quantify recently increased oceanic heat flux intermediate-depth (~150–900 m) warm Atlantic Water (AW) surface mixed layer sea ice. The upward release AW regulated by stability overlying halocline, which we has weakened substantially in recent years. Shoaling also contributed, with winter 2017–18 showing at only 80 m depth, just below wintertime layer,...
Arctic Ocean primary productivity is limited by light and inorganic nutrients. With sea ice cover declining in recent decades, nitrate limitation has been speculated to become more prominent. Although much learned about supply from general patterns of ocean circulation water column stability, a quantitative analysis requires dedicated turbulence measurements that have only started accumulate the last dozen years. Here we present new observations turbulent vertical flux Laptev Sea, Baffin...
Abstract The Filchner‐Ronne Ice Shelf, fringing the southern Weddell Sea, is Antarctica's second largest ice shelf. At present, basal melt rates are low due to active dense water formation; however, model projections suggest a drastic increase in future enhanced inflow of open‐ocean warm water. Mooring observations from 2014 2016 along eastern flank Filchner Trough (76°S) revealed distinct seasonal cycle with if Warm Deep Water during summer and autumn. Here we present extended time series...
Abstract The Filchner‐Ronne Ice Shelf (FRIS) is characterized by moderate basal melt rates due to the near‐freezing waters that dominate wide southern Weddell Sea continental shelf. We revisited region in austral summer 2018 with detailed hydrographic and noble gas surveys along FRIS. FRIS front was High Salinity Water (HSSW) Ronne Depression, (ISW) on its eastern flank, an inflow of modified Warm Deep (mWDW) entering through Central Trough. Filchner Trough dominated HSSW‐sourced ISW, likely...
A breeding colony of notothenioid icefish (Neopagetopsis ionah, Nybelin 1947) globally unprecedented extent has been discovered in the southern Weddell Sea, Antarctica. The was estimated to cover at least ∼240 km2 eastern flank Filchner Trough, comprised fish nests a density 0.26 per square meter, representing an total ∼60 million active and associated biomass >60,000 tonnes. majority were each occupied by 1 adult guarding 1,735 eggs (±433 SD). Bottom water temperatures measured across...
Mesoscale eddies are important to many aspects of the dynamics Arctic Ocean. Among others, they maintain halocline and interact with Atlantic Water circumpolar boundary current through lateral eddy fluxes shelf-basin exchanges. also for transporting biological material modifying sea ice distribution. Here, we review what is known about their impacts in Ocean context rapid climate change. Eddy kinetic energy (EKE) a proxy mesoscale variability ocean due eddies. We present first quantification...
Abstract The transport of oceanic heat towards the Antarctic continental margin is central to mass balance Ice Sheet. Recent modeling efforts challenge our view on where and how on-shelf flux occurs, suggesting that it largest dense shelf waters cascade down slope. Here we provide observational evidence supporting this claim. Using records from moored instruments, link downslope flow water Filchner overflow upslope warm water.
Central Arctic properties and processes are important to the regional global coupled climate system. The Multidisciplinary drifting Observatory for Study of Climate (MOSAiC) Distributed Network (DN) autonomous ice-tethered systems aimed bridge gaps in our understanding temporal spatial scales, particular with respect resolution Earth system models. By characterizing variability around local measurements made at a Observatory, DN covers both interactions involving ocean-ice-atmosphere...
Abstract We quantify Atlantic Water heat loss north of Svalbard using year‐long hydrographic and current records from three moorings deployed across the Branch boundary in 2012–2013. The loses annually on average 16 W m −2 during eastward propagation along upper continental slope. largest vertical fluxes >100 occur episodically autumn early winter. Episodes sea ice imported November 2012 February 2013 coincided with large ocean‐to‐ice fluxes, which effectively melted sustained open water...
Continental slopes – steep regions between the shelf break and abyssal ocean play key roles in climatology ecology of Arctic Ocean. Here, through review synthesis, we find that narrow slope contribute to ecosystem functioning disproportionately size habitat area (∼6% total Ocean area). Driven by inflows sub-Arctic waters steered topography, boundary currents transport boreal properties particle loads from Atlantic Pacific Oceans along-slope, thus creating both along cross-slope connectivity...
Abstract A 15‐year (2004–2018) record of mooring observations from the upper 50 m ocean in eastern Eurasian Basin reveals increased current speeds and vertical shear, associated with an increasing coupling between wind, ice, over 2004–2018, particularly summer. Substantial increases shears are dominated by a two times amplification currents semidiurnal band, which includes tides wind‐forced near‐inertial oscillations. For first time strengthened shear observed to coincide weakening...
Abstract Floating ice shelves are the Achilles’ heel of Antarctic Ice Sheet. They limit Antarctica’s contribution to global sea level rise, yet they can be rapidly melted from beneath by a warming ocean. At Filchner-Ronne Shelf, decline in formation may increase basal melt rates and accelerate marine sheet mass loss within this century. However, understanding tipping-point behavior largely relies on numerical models. Our new multi-annual observations five hot-water drilled boreholes through...
Abstract Filchner‐Ronne Ice Shelf (FRIS) is the world's largest ice shelf by volume. It helps regulate Antarctica's contribution to global sea level rise, and water mass transformations within sub‐ice‐shelf cavity produce globally important dense masses. Rates of basal melting are relatively low, however, as production cold (−1.9°C) High Salinity Water over Weddell Sea continental isolates from large‐scale inflow warm water. Nevertheless, a narrow (−1.4°C) Modified Warm Deep (MWDW) that hugs...
Dense, cold waters formed on Antarctic continental shelves descend along the margin, where they mix with other Southern Ocean to form Bottom Water (AABW). AABW then spreads into deepest parts of all major ocean basins, isolating heat and carbon from atmosphere for centuries. Despite AABW’s key role in regulating Earth’s climate long time scales recording conditions, remains poorly observed. This lack observational data is mostly due two factors. First, originates shelf slope situ...
Hydrographic and stable isotope (δ 18 O) data from four summer surveys in the Laptev Sea are used to derive fractions of sea‐ice meltwater river water. Sea‐ice found be correlated water fractions. While initial heat discharge is too small melt observed 0–158 km 3 meltwater, arctic rivers contain suspended particles colored dissolved organic material that preferentially absorb solar radiation. Accordingly, content surface waters But years when largely absent within layer, absolute values...
Siberian river water is a first-order contribution to the Arctic freshwater budget, with Ob, Yenisey, and Lena supplying nearly half of total surface flux. However, few details are known regarding where, when, how transverses vast shelf seas. This paper investigates mechanism, variability, pathways fresh Kara Sea outflow through Vilkitsky Strait toward Laptev Sea. We utilize high-resolution ocean model recent shipboard observations characterize freshwater-laden Current (VSC), shed new light...
Abstract Along with changes in sea ice extent, thickness, and drift speed, Arctic regime is characterized by a decrease of fast season reduction extent. The most extensive cover the develops southeastern Laptev Sea. Using weekly operational charts produced Antarctic Research Institute (AARI, Russia) from 1999 to 2013, we identified five main key events that characterize annual evolution Linking occurrence atmospheric forcing, bathymetry, freezeup, melt onset, examined processes driving...
Abstract Two full‐year mooring records of sea‐ice, physical, and bio‐optical parameters illuminate tight temporal coupling between the retreating seasonal ice edge summer phytoplankton bloom on Laptev Sea shelf. Our showed no sign pelagic under‐ice blooms despite available nutrients thinning sea in early summer, presumably because stratification had not yet developed. Chlorophyll were detected immediately after retreated late May 2014 July 2015. Despite radically different timing, similar...
In this paper, we investigate the seasonal and spatial variability of stratification on Siberian shelves with a case study from Laptev Sea based shipboard hydrographic measurements, year-round oceanographic mooring records 2013 to 2014 chemical tracer-based water mass analyses. summer 2013, weak onshore-directed winds caused spreading riverine waters throughout much eastern central shelf. contrast, strong southerly in diverted freshwater northeast, which resulted 50% less river significantly...
Abstract Large amounts of atmospheric carbon can be exported and retained in the deep sea on millennial time scales, buffering global warming. However, while Barents Sea is one most biologically productive areas Arctic Ocean, retention times were thought to short. Here we present observations, complemented by numerical model simulations, that revealed a widespread lateral injection approximately 2.33 kt C d −1 from shelf some 1,200 m Nansen Basin, driven Bottom Water transport. With...