45 research outputs found
Five-member ensemble wave forecast for the R/V Mirai 2023 Arctic Ocean expedition using different sea ice forcing
Get PDFThe 14th Symposium on Polar Science/Interdisciplinary sessions [IA] Arctic Research, Thu. 16 Nov. / 2F Auditorium, National Institute of Polar Researchconference objec
Spectral downshift of Three-wave system and Bichromatic waves under “sea ice”
Get PDFThe 14th Symposium on Polar Science/Interdisciplinary sessions [IA] Arctic Research, Thu. 16 Nov. / 2F Auditorium, National Institute of Polar Researchconference objec
Observation of wave propagation over 1,000 km into Antarctica winter pack ice
Full text linkA drifting wave-ice buoy, which was configured by mounting the OpenMetBuoy on
an ad hoc floating platform that we named Medusa, was deployed at the
L\"utzow-Holm Bay (LHB) marginal ice zone in Antarctica on 4 Feb 2022 during
the 63rd Japanese Antarctica research expedition. The wave-ice buoy,
Medusa-766, survived the Antarctica winter as the measurement duration reached
333 days. During the winter months, it was located deep in the ice cover with
the shortest distance to the ice-free Southern Ocean over 1,000 km; at this
time, there was evidence of ocean wave signals at the buoy position. Using the
directional wave spectra obtained from the ECMWF's reanalysis, we show that the
Medusa-766 observed waves were likely generated by an extratropical cyclone in
the Southern Ocean. Wave-induced ice breakup potential for such an event could
extend 100s km into the ice field. When Medusa-766 was in LHB in the summer
months, it did not detect sizeable wave energy despite the low sea ice
concentration extent even during on-ice waves events. Characterising the
considerable differences in the wave attenuation at LHB is needed to elucidate
the relative contribution of ocean waves to the unstable LHB fast ice. The
success of Medusa-766 demonstrates the robustness of the general design,
hardware, firmware, and the high sensitivity of the sensor used. The result is
promising for future LHB wave-ice interaction research
An affordable and customizable wave buoy for the study of wave-ice interactions: design concept and results from field deployments
Full text linkIn the polar regions, the interaction between waves and ice has a crucial
impact on the seasonal change in the sea ice extent. However, our comprehension
of this phenomenon is restricted by a lack of observations, which, in turn,
results in the exclusion of associated processes from numerical models. In
recent years, availability of the low-cost and accurate Inertial Motion Units
has enabled the development of affordable wave research devices. Despite
advancements in designing innovative open-source instruments optimized for
deployment on ice floes, their customizability and survivability remain
limited, especially in open waters. This study presents a novel design concept
for an affordable and customizable wave buoy, aimed for wave measurements in
marginal ice zones. The central focus of this wave buoy design is the
application of 3D printing as rapid prototyping technology. By utilizing the
high customizability offered by 3D printing, the previously developed
solar-powered wave buoy was customized to install a battery pack to continue
the measurements in the high latitudes for more than several months.
Preliminary results from field deployments in the Pacific and Arctic Oceans
demonstrate that the performance of the instruments is promising. The accuracy
of frequency wave spectra measurements is found to be comparable to that of
considerably more expensive instruments. Finally, the study concludes with a
general evaluation of using rapid prototyping technologies for buoy designs and
proposes recommendations for future designs
An affordable and customizable wave buoy for the study of wave-ice interactions: design concept and results from field deployments
Get PDFThe interaction between waves and ice has a crucial impact on the seasonal change in the sea ice extent. However, our comprehension of this phenomenon is restricted by a lack of observations. In recent years, availability of the low-cost and accurate Inertial Motion Units has enabled the development of affordable wave research devices. Despite advancements in designing innovative open-source instruments optimized for deployment on ice floes, their customizability and survivability remain limited, especially in open waters. This study presents a novel design concept for an affordable and customizable wave buoy, aimed for wave measurements in marginal ice zones. The central focus of this wave buoy design is the application of 3D printing as rapid prototyping technology. By utilizing the high customizability offered by 3D printing, the previously developed solar-powered wave buoy was customized to install a battery pack. Preliminary results from field deployments in the Pacific and Arctic Oceans demonstrate that the performance of the instruments is promising. The accuracy of frequency wave spectra measurements is found to be comparable to that of considerably more expensive instruments. Finally, the study concludes with a general evaluation of using rapid prototyping technologies for buoy designs and proposes recommendations for future designs
Observation of anomalous spectral downshifting of waves in the Okhotsk Sea Marginal Ice Zone
Get PDFWaves in the Marginal Ice Zone in the Okhotsk Sea are less studied compared to the Antarctic and Arctic. In February 2020, wave observations were conducted for the first time in the Okhotsk Sea, during the observational program by Patrol Vessel Soya. A wave buoy was deployed on the ice, and in situ wave observations were made by a ship-borne stereo imaging system and Inertial Measurement Unit. Sea ice was observed visually and by aerial photographs by drone, while satellite synthetic aperture radar provided basin-wide spatial distribution. On 12 February, a swell system propagating from east northeast was detected by both the stereo imaging system and the buoy-on-ice. The wave system attenuated from 0.34 m significant wave height to 0.25 m in about 90 km, while the wave period increased from 10 s to 15–17 s. This anomalous spectral downshifting was not reproduced by numerical hindcast and by applying conventional frequency-dependent exponential attenuation to the incoming frequency spectrum. The estimated rate of spectral downshifting, defined as a ratio of momentum and energy losses, was close to that of uni-directional wave evolution accompanied by breaking dissipation: this indicates that dissipation-driven nonlinear downshifting may be at work for waves propagating in ice
2023 Breakup of the land-fast ice in Lützow-Holm bay, Antarctica
Get PDFThe 14th Symposium on Polar Science/Ordinary sessions [OM] Polar meteorology and glaciology, Tue. 14 Nov. / 2F Auditorium, National Institute of Polar Researchconference objec
A dataset of direct observations of sea ice drift and waves in ice
Get PDFVariability in sea ice conditions, combined with strong couplings to the
atmosphere and the ocean, lead to a broad range of complex sea ice dynamics.
More in-situ measurements are needed to better identify the phenomena and
mechanisms that govern sea ice growth, drift, and breakup. To this end, we have
gathered a dataset of in-situ observations of sea ice drift and waves in ice. A
total of 15 deployments were performed over a period of 5 years in both the
Arctic and Antarctic, involving 72 instruments. These provide both GPS drift
tracks, and measurements of waves in ice. The data can, in turn, be used for
tuning sea ice drift models, investigating waves damping by sea ice, and
helping calibrate other sea ice measurement techniques, such as satellite based
observations
A position and wave spectra dataset of Marginal Ice Zone dynamics collected around Svalbard in 2022 and 2023
Get PDFSea ice is a key element of the global Earth system, with a major impact on global climate and regional weather. Unfortunately, accurate sea ice modeling is challenging due to the diversity and complexity of underlying physics happening there, and a relative lack of ground truth observations. This is especially true for the Marginal Ice Zone (MIZ), which is the area where sea ice is affected by incoming ocean waves. Waves contribute to making the area dynamic, and due to the low survival time of the buoys deployed there, the MIZ is challenging to monitor. In 2022-2023, we released 79 OpenMetBuoys (OMBs) around Svalbard, both in the MIZ and the ocean immediately outside of it. OMBs are affordable enough to be deployed in large number, and gather information about drift (GNSS position) and waves (1-dimensional elevation spectrum). This provides data focusing on the area around Svalbard with unprecedented spatial and temporal resolution. We expect that this will allow to perform validation and calibration of ice models and remote sensing algorithms
