Article
Geosciences, Multidisciplinary
Lixin Qu, Leif Thomas, Jonathan Gula
Summary: The study found that storm-generated near-inertial waves (NIWs) were observed on the seafloor of the Straits of Florida, and numerical simulations provided evidence that these waves can enhance mixing in the seafloor of the straits. This mixing could potentially influence benthic deep-water coral ecosystems and properties of intermediate water masses.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Mechanics
Mohnish Kapil, Bruce R. Sutherland, Sridhar Balasubramanian
Summary: Laboratory experiments investigate the evolution and sedimentation of a particle-bearing jet advancing along a horizontal or downward-sloping boundary in a uniform-density ambient fluid. The study reveals that the teardrop-shaped sediment bed formed by particle settling follows a Gaussian velocity profile within the jet, with additional influence from the morphology of the bed on particle settling.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Limnology
Marie-Elodie Perga, Camille Minaudo, Tomy Doda, Florent Arthaud, Harsh Beria, Hannah E. Chmiel, Nicolas Escoffier, Thibault Lambert, Raphaelle Napolleoni, Biel Obrador, Pascal Perolo, Janine Ruegg, Hugo Ulloa, Damien Bouffard
Summary: By studying high-temporal resolution time series of dissolved oxygen concentration and temperature in 14 mountain lakes, it was found that the duration of bottom hypoxia under ice varies greatly among lakes and years. The variability of hypoxia duration is primarily explained by changes in the decay rate of dissolved oxygen above the lake bottom, which is linked to physical controls such as deep-water warming. The study also showed that the summer light climate is a key driver of the dissolved oxygen decay rate and hypoxia duration under the ice.
LIMNOLOGY AND OCEANOGRAPHY
(2023)
Article
Engineering, Marine
Ioannis Y. Georgiou, Francesca Messina, Md Mohiuddin Sakib, Shan Zou, Madeline Foster-Martinez, Martijn Bregman, Christopher J. Hein, Michael S. Fenster, Justin L. Shawler, Kaitlyn McPherran, Arthur C. Trembanis
Summary: A numerical model was developed to understand the hydrodynamic and geomorphic controls in the rapidly evolving inlet-spit system and the sediment transport pathways. The model results confirmed previous analysis and hypothesis that most of the sand transport occurs nearshore and in deeper sinks within Fishing Point, with only finer sand sizes being transported around the spit. The model also showed that sand transport towards the south increases along Wallops Island and demonstrated the punctuated process of coarser sediment bypassing proportional to storms.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Review
Oceanography
Xiaohui Xie, Yan Wang, Xiaohui Liu, Jun Wang, Dongfeng Xu, Tongya Liu, Jinlin Ji, Dongsheng Zhang, Chunsheng Wang, Dake Chen
Summary: This study identifies a potential energy transfer pathway from surface geostrophic eddies to abyssal small-scale turbulence. Strong near-bottom anticyclonic circulations are generated following the passage of surface geostrophic eddies across seamounts, driving enhanced turbulent mixing and thickened bottom mixed layers. This mechanism may play a significant role in the oceanic energy balance and water mass transformation in the abyssal ocean.
PROGRESS IN OCEANOGRAPHY
(2022)
Article
Geosciences, Multidisciplinary
Muneer Ahammad, Jonathan A. Czuba, Allison M. Pfeiffer, Brendan P. Murphy, Patrick Belmont
Summary: The study simulated downstream bed elevation changes resulting from different volumes and grain size distributions of sediment inputs in mountain rivers, finding that bed response is primarily influenced by sediment-pulse grain size and distribution. Mixed size sediment pulses may have the largest downstream impact.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2021)
Article
Environmental Sciences
Sarah Paradis, Marta Arjona-Camas, Miguel Goni, Albert Palanques, Pere Masque, Pere Puig
Summary: Submarine canyons play a crucial role in transporting sediment and organic matter to deep-sea environments. This study found that natural events such as storms and river floods, as well as human activities like bottom trawling, contribute to the inputs of sediment and organic matter. Bottom trawling not only increases the magnitude of particle fluxes, but also alters the composition of organic carbon, potentially affecting benthic communities.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Limnology
Jeffrey R. Nielson, Stephen M. Henderson
Summary: In a stratified lake, internal seiche-induced oscillation of the bottom boundary layer controls the mixing rates. High-resolution measurements of temperature and velocity show that mixing is more effective during downslope flow compared to upslope flow. This finding suggests the potential importance of downslope flow in other environments.
LIMNOLOGY AND OCEANOGRAPHY
(2022)
Article
Geosciences, Multidisciplinary
Kirstin Schulz, Stefan Buttner, Andreas Rogge, Markus Janout, Jens Holemann, Tom P. Rippeth
Summary: This study provides the first direct evidence of an intermediate nepheloid layer over the Laptev Sea continental slope in the Arctic Ocean. The strong mid-water turbulence is likely caused by downslope currents displacing isopycnals, with such events mostly occurring during ice free periods in the summer. These episodic transport events are expected to become more frequent in the future as Arctic sea ice continues to decline.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Environmental Sciences
Jiarui Qi, Yige Jing, Chao Chen, Jinfeng Zhang
Summary: This paper utilizes the FVCOM-SWAN wave-current-sediment model to simulate the tidal current, wave, and suspended sediment concentration (SSC) in the sea area near Weifang Port, China. By introducing a modified sediment-settling-velocity formula, the SSCs calculated by the modified model are shown to be closer to the measured data compared to the original model. The results indicate that the modified model can effectively describe the hydrodynamic characteristics and sediment movement in the study area.
Article
Environmental Sciences
Guangpeng Liu, Annalisa Bracco, Alexandra Sitar
Summary: Submesoscale circulations play a significant role in the vertical transport of neutrally buoyant particles in the northern Gulf of Mexico. The influence of submesoscale dynamics is greater in winter compared to other seasons, with upwelling into the mixed layer being a major contributor to vertical fluxes in the large mesoscale eddies. The distribution of diffusivities varies in different regions of the Gulf, with higher values in the eastern portion where submesoscale circulations are more intense.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Multidisciplinary Sciences
Kay I. Ohshima, Yasushi Fukamachi, Masato Ito, Kazuki Nakata, Daisuke Simizu, Kazuya Ono, Daiki Nomura, Gen Hashida, Takeshi Tamura
Summary: New research reveals that underwater frazil ice plays a crucial role in the formation of Antarctic Bottom Water (AABW) in the Cape Darnley polynya. This underwater ice prevents surface-cover ice formation, allowing for efficient ice production and providing high-salinity source water for AABW.
Article
Physics, Fluids & Plasmas
S. Zahedi, P. Aghsaee, L. Boegman
Summary: The study reveals that boundary layer instability beneath internal solitary waves of depression may lead to wave-energy dissipation and drive localized mixing and resuspension in coastal regions. The dissipation rate of turbulent kinetic energy in the boundary layer is influenced by wave characteristics and Reynolds number.
PHYSICAL REVIEW FLUIDS
(2021)
Article
Environmental Sciences
Clare Bradshaw, Martin Jakobsson, Volker Bruechert, Stefano Bonaglia, Carl-Magnus Moerth, Julia Muchowski, Christian Stranne, Mattias Skoeld
Summary: Research has shown that bottom trawling in the Baltic Sea has long-lasting physical and biogeochemical effects on the seabed, altering topography and sediment suspension for days to weeks and potentially disturbing sediment biogeochemical processes. This prolonged disturbance could lead to a persistence of elevated turbidity beyond the trawling area.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Oceanography
Renzhi Li, George Voulgaris, Ya Ping Wang
Summary: In estuarine environments, tidal variation affects turbulence and sediment transport near the bed. This study collected in situ turbulence and sediment data from the subaqueous Yangtze delta to gain insights into turbulence structure and sediment mobility. The results show that flood and ebb tides have different effects on turbulence and sediment dynamics, with ejections and sweeps dominating Reynolds stress and sediment resuspension. Inward and outward interactions have limited contribution to Reynolds stress and are more important for fine sediment resuspension.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Oceanography
Yuliang Zhu, Mingze Lin, Xiaoteng Shen, Michael Fettweis, Ying Zhang, Jinfeng Zhang, Qilong Bi, Zi Wu
Summary: This study investigates the impact of microalgae on suspended fine-grained sediments through laboratory experiments and modeling. The results demonstrate that the shear rate plays a dominant role in the aggregation process, and the presence of microalgae enhances the aggregation. Different algal species and concentrations have a significant influence on the size distribution and average size of the aggregates. The developed model effectively simulates the aggregates and has the potential to track the properties of microalgae-associated sediment flocs.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Engineering, Environmental
Xiaoteng Shen, Hong Huo, Ying Zhang, Yuliang Zhu, Michael Fettweis, Qilong Bi, Byung Joon Lee, Jerome P. -Y. Maa, Qiqing Chen
Summary: This study examines the effects of different organic matter on the flocculation of anthropogenic microplastics and finds that cationic and neutral organic matter have a more significant promoting effect on the growth of microplastic flocs.