A5027457382- Arctic and Antarctic ice dynamics
- Underwater Acoustics Research
- Methane Hydrates and Related Phenomena
- Geological Studies and Exploration
- Atmospheric and Environmental Gas Dynamics
- Oceanographic and Atmospheric Processes
- Marine animal studies overview
- Cryospheric studies and observations
- Arctic and Russian Policy Studies
- Offshore Engineering and Technologies
- Seismic Imaging and Inversion Techniques
- Scientific Research and Discoveries
- Reservoir Engineering and Simulation Methods
- Acoustic Wave Phenomena Research
- Seismic Waves and Analysis
- Climate change and permafrost
- Underwater Vehicles and Communication Systems
- Advanced Computational Techniques and Applications
- Technology Assessment and Management
- Spacecraft and Cryogenic Technologies
- Distributed and Parallel Computing Systems
- Spacecraft Design and Technology
- Big Data Technologies and Applications
- Land Use and Ecosystem Services
- Ultrasonics and Acoustic Wave Propagation
Nansen Environmental and Remote Sensing Center
2015-2024
Scripps Institution of Oceanography
2017-2024
University of California, San Diego
2024
University of Bath
2024
Nansen International Environmental and Remote Sensing Center
2008-2023
Uni Research (Norway)
2023
Acoustics (Norway)
2021
Norwegian Polar Institute
2018
Instytut Oceanologii Polskiej Akademii Nauk
2017
Polish Academy of Sciences
2017
Acoustics play a central role in mankind's interactions with the ocean and life within. Passive listening to "soundscapes" informs us about physical bio-acoustic environment from earthquakes communication between fish. Active acoustic probing of topography, currents temperature, abundance type marine vital fisheries biodiversity related interests. The two together multi-purpose network can lead discovery improve understanding ecosystem health biodiversity, climate variability change, hazards...
Today there is severe lack of in situ observations the Arctic Ocean which are needed to understand physical, biogeochemical, and ecological processes support development ocean forecasting services. These services will be important as ship traffic, tourism other marine industries develop region. To sustain long-term Arctic, robust platforms equipped with autonomous sensors required collect high-quality measurements whole water column from seafloor sea ice surface. In present HiAOOS project,...
Climate change in the Arctic is both a potential threat and opener for new opportunities sustainable development of region. Better access to data, methods tools, as well better documentation these are needed advance science support decision-making on public private sector. While local, national regional communities different parts face individual challenges due climate change, they experience similar problems when gathering analysing data address issues.The Ocean one least explored oceans...
The dramatic reduction of sea ice in the Arctic Ocean will increase human activities coming years. This activity be driven by increased demand for energy and marine resources an accessible to ships. Oil gas exploration, fisheries, mineral extraction, transportation, research development, tourism, search rescue pressure on vulnerable environment. Technologies that allow synoptic situ observations year-round are needed monitor forecast changes atmosphere-ice-ocean system at daily, seasonal,...
A characteristic surface duct beneath the sea-ice in Marginal Ice Zone causes acoustic waves to be trapped and continuously interact with sea-ice. The reflectivity of depends on thickness, elastic properties, its roughness. This work focuses influence roughness long-range propagation, how well arrival structure can predicted by full wave integration model OASES. In 2013, signals centered at 900 Hz were transmitted every hour for three days between ice-tethered buoys a drifting network Fram...
Rapid Arctic warming drives profound change in the marine environment that have significant socio-economic impacts within and beyond, including climate weather hazards, food security, transportation, infrastructure planning resource extraction. These concerns drive efforts to understand predict environmental motivate development of an Region Component Global Ocean Observing System (ARCGOOS) capable collecting broad, sustained observations needed support these endeavors. This paper provides a...
Acoustic experiments using an integrated ice station were carried out during August 2012 and September 2013 in the Marginal Ice Zone (MIZ) of Fram Strait. The two lasted four days each collected under-ice acoustic recordings together with wave-in-ice meteorological data. Synthetic aperture radar satellite data provided information on regional conditions. Four major components soundscape identified: ship cavitation noise, seismic airgun marine mammal vocalizations, natural background noise....
Abstract A pilot acoustic tomography program in Fram Strait during 2008–2009 measured a year‐long record of travel times along 130 km range path crossing the West Spitsbergen Current. Individual ray arrivals were not observed. Rather, arrival patterns consisted single, stable, broad pulse about 100 ms duration. Travel time variations ±0.15 s recorded vigorous mesoscale environment region and seasonal cycle. To estimate ocean temperature from data an inverse scheme employed high‐resolution...
The application of ocean acoustic tomography in Fram Strait requires a careful assessment the accuracy to which estimates sound speed from can be converted temperature. environment is turbulent, with warm, salty, northward-flowing North Atlantic water interacting cold, fresh, southward-flowing Arctic water. nature this suggests that salinity could play an important role respect speed. properties temperature and were examined using climatological situ glider data. In cold water, factor about...
Acoustic tomography systems have been deployed in Fram Strait over the past decade to complement existing observing there. The observed acoustic arrival patterns are unusual, however, consisting of a single, broad pulse, with no discernible repeating or individual ray arrivals. nature these arrivals is caused by vigorous scattering from small-scale processes that dominate ocean variability Strait. Simple models for internal wave and mesoscale were constructed tailored match moored...
Abstract Estimation of the exchange seawater various properties between Arctic and North Atlantic Oceans presents a challenging observational problem. The strong current systems within Fram Strait induce recirculations turbulent ocean environment dominated by mesoscale variations 4–10-km scale. By employing simple parameterized model for variability Strait, authors examine ability line array closely spaced moorings an acoustic tomography to measure average sound speed, proxy variable...
The Beaufort duct (BD) is a subsurface sound channel in the western Arctic Ocean formed by cold Pacific Winter Water (PWW) sandwiched between warmer Summer (PSW) and Atlantic (AW). Sound waves can be trapped this travel long distances without experiencing lossy surface/ice interactions. This study analyzes BD vertical temporal variability using moored oceanographic measurements from two yearlong acoustic transmission experiments (2016-2017 2019-2020). focus on normal mode propagation through...
An ocean acoustic tomography system consisting of three moorings with low frequency, broadband transceivers and a moored receiver located approximately in the center triangle formed by was installed central, deep-water part Fram Strait during 2010–2012. Comparisons receptions predictions based on hydrographic sections show that oceanographic conditions result complex arrival patterns which it is difficult to resolve identify individual arrivals. In addition, early arrivals are unstable,...
Ocean acoustic tomography depends on a suitable reference ocean environment with which to set the basic parameters of inverse problem. Some problems may require that includes small-scale variations from internal waves, small mesoscale, or spice. Tomographic inversions employ data stable shadow zone arrivals, such as those have been observed in North Pacific and Canary Basin, are an example. Estimating temperature unique obtained Fram Strait is another The addition variability augment smooth...
In November, 2001, the R/V "Point Sur" departed from Moss Landing Marine Laboratories pier with first prototype of a high-Q, tunable organ pipe projector. The test Teledyne Webb Research (TWR) organ-pipe was successfully conducted on 11.09.2001. TWR sound source demonstrated exceptional performance. It coherent, efficient, powerful, and had unlimited operational depth, as well minimum level high frequency harmonic content. projector uses narrow-band, highly efficient resonator, which is...
Mesoscale eddies are frequently observed in the Greenland and Barents Seas' marginal ice zone (MIZ). The objective of this study was to investigate hypothesis that acoustic hotspots along ice-edge region due mesoscale eddy currents interacting with broken-up floes MIZ. To test hypothesis, ambient-noise case studies were carried out during MIZEX 85-87 SIZEX 89 field experiments. In each experiment, localized visually from aircraft by use satellite remote-sensing data obtained near real time....
A regional ocean model for Fram Strait provides a framework interpretation of the variability and structure acoustic tomography arrivals. The eddy-permitting (52 vertical levels 4.5 km horizontal resolution) was evaluated using long-term moored hydrography data time series depth-range averaged temperature obtained from inversion measurements. Geometric ray modeling fields reproduces measured arrival experiment. combination models gives insights into propagation during winter spring....
A sonobuoy field was deployed in the Marginal Ice Zone of Fram Strait June 2011 to study spatial variability ambient noise. High noise levels observed at 10–200 Hz are attributed distant (1400 km range) seismic exploration. The decreased with range into ice cover; reduction is fitted by a spreading loss model frequency-dependent attenuation factor less than for under-ice interior Arctic propagation. Numerical modeling predicts transmission same order as level and indicates significant...
The deep and wide Fram Strait between Greenland Spitzbergen is the main influx efflux gate to Arctic Basin. Although major resources are invested in measurements of current temperature here (http://asof.npoar.no), flux estimates still have significant deficiencies errors. Our objective build, test, validate use an innovated integrated observing modeling system, including acoustic tomography, for improved monitoring volume, heat freshwater transports Strait. As part DAMOCLES-IP, (=Developing...
Underwater acoustics has developed into a powerful tool for monitoring the climate of ocean basins. Acoustic travel-times are direct indication temperature and give large-scale average heat content. A recent experiment called Coordinated Arctic Thermometry Experiment (CAATEX) is prime example method in region known to be experiencing most rapid response anthropogenic forcing. In CAATEX, two 35 Hz acoustic transceiver moorings, one Nansen Basin Beaufort Sea, were deployed along with four...
The Arctic Ocean is possibly the least explored ocean in world. With reducing sea ice and increasing human activities, observations are demand. Multipurpose acoustic networks for tomography, under navigation of gliders passive acoustics beginning to be employed Fram Strait supplementing standard oceanographic moorings ice-ocean measurements from tethered measurement platforms interior Arctic. Seafloor based fiberoptic cable systems also being planned high bandwidth local process studies....
Reflection of sound from ice sheets floating on water is simulated using Thomson and Haskell's method matrix propagation. The reflection coefficient computed as a function incidence angle frequency for selected parameters uniform sheet two layered sheets. At some angles frequencies the has very low values. It shown that this related to generation Lamb waves in ice. propagation also provides dispersion equation plate loaded with fluid one side vacuum other. Finally concept beam displacement...
The under-ice acoustic transmission experiment of 2013, conducted under ice cover in the Fram Strait, was analyzed for bottom interactions purpose developing a model seabed. Using signals, as well data from other sources, including cores, gravimetric, refraction, and seismic surveys, it deduced that seabed may be modeled thin surficial layer overlaid on deeper sediment. modeling based Biot–Stoll propagation porous sediments, aided by more recent developments improve parameter estimation...
Abstract Due to the efficient propagation of sound in water, deep ocean propagates such great distances that soundscapes are influenced not only by local conditions but also distant sources. Ocean Sound is now an Essential Variable within Global Observing System making passive acoustic monitoring routine. Active probing environment informs us about topography, currents and temperature, abundance type marine life vital fisheries biodiversity related interests.Efficient foundation a proposed...