Article
Oceanography
Robert H. Nazarian, Christian M. Burns, Sonya Legg, Maarten C. Buijsman, Harpreet Kaur, Brian K. Arbic
Summary: Submarine canyons dissipate a significant fraction of internal tide energy, contributing approximately 3.2%-7.8% of global internal tide input. This phenomenon is substantial on a global scale.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2021)
Article
Multidisciplinary Sciences
Jared L. Callaham, James Koch, Bingni W. Brunton, J. Nathan Kutz, Steven L. Brunton
Summary: Traditional physics-based modeling relies on approximating observed dynamics as a balance between dominant processes within asymptotic regimes, but researchers have proposed a new approach using equation space to identify neglected terms in non-asymptotic regimes. Their data-driven balance models successfully delineate dominant physics in systems like turbulence, combustion, nonlinear optics, geophysical fluids, and neuroscience.
NATURE COMMUNICATIONS
(2021)
Article
Oceanography
Mark E. Inall, J. Alexander Brearley, Sian F. Henley, Alexander D. Fraser, Sarah Reed
Summary: This study quantified the surface layer turbulent and fine structure under landfast ice in Antarctica, revealing that landfast ice significantly reduces turbulence levels and affects energy dissipation. The regional effects of landfast ice and the contributions of wind and tides to the turbulent kinetic energy budget in the surface ocean exhibit significant variations.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Environmental Sciences
Stephen Plont, Durelle T. Scott, Erin R. Hotchkiss
Summary: Stream confluences play a significant role in connecting previously independent landscapes in freshwater networks. However, the influence of confluences on the transport, mixing, and fate of organic matter (OM) and inorganic nutrients at the scale of river networks has been poorly studied. To understand this influence, the researchers conducted sampling campaigns at five confluences and found that dissolved OM and nutrients mixed non-conservatively downstream of the confluences. The geomorphic variability, water residence time, and microbial respiration differed between reaches upstream and downstream of the confluences, suggesting that biogeochemical processes within the confluence mixing zone drive the non-conservative mixing downstream. This study highlights the importance of considering the unique functional role of confluences in water resource management.
WATER RESOURCES RESEARCH
(2023)
Review
Geochemistry & Geophysics
Melissa Moulton, Sutara H. Suanda, Jessica C. Garwood, Nirnimesh Kumar, Melanie R. Fewings, James M. Pringle
Summary: The exchange of material in the nearshore region, from the shoreline to a few kilometers offshore, plays a crucial role in determining the concentrations of pathogens and nutrients near the coast, as well as the transport of larvae. Various cross-shore exchange mechanisms, such as winds, currents, and waves, can influence this process. A framework has been developed to estimate the relative importance of these mechanisms and determine their impact on particle behavior.
ANNUAL REVIEW OF MARINE SCIENCE
(2023)
Article
Mechanics
Nathan E. Grube, M. Pino Martin
Summary: The study explores the discrepancy between theoretical predictions and computational/experimental results regarding the Reynolds stress tensor in vortical turbulence interacting with a normal shock wave at Mach 2 or greater. It is found that the redistribution of energy between transverse and streamwise Reynolds stresses is influenced by the wavelengths of the vortical waves emitted during the interaction, leading to the dominance of R-11. A quantitative model based on this understanding of flow physics accurately predicts anisotropy levels observed in direct numerical simulation data.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Multidisciplinary Sciences
Teagan E. Bate, Megan E. Varney, Ezra H. Taylor, Joshua H. Dickie, Chih-Che Chueh, Michael M. Norton, Kun-Ta Wu
Summary: The study explores mixing dynamics of active fluids with spatiotemporally-varying activity levels. Results show a transition from diffusion-like to superdiffusion-like behaviors, with mixing efficacy depending on the Peclet number and spatial distribution of activities. Active fluid mixing involves complex coupling between active stress distribution and ATP transport.
NATURE COMMUNICATIONS
(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
Ecology
Ya-Jou Chen, Pok Man Leung, Perran L. M. Cook, Wei Wen Wong, Tess Hutchinson, Vera Eate, Adam J. Kessler, Chris Greening
Summary: This study investigated the relationships between microbial community composition and biogeochemical processes in coastal sediments exposed to varying levels of hydrodynamic disturbance. The findings suggest that hydrodynamic disturbance plays a critical role in controlling microbial community assembly and biogeochemical processes in coastal sediments. The study provides insights into the mechanisms underlying the interactions between microbial communities and biogeochemical dynamics in these unique environments.
Article
Geosciences, Multidisciplinary
Hemantha W. Wijesekera, Ewa Jarosz, David W. Wang, Conrad A. Luecke, William J. Teague, Kyung-Il Chang, Jae Hak Lee, SungHyun Nam, Hong-Sik Min, KyungJae Lee
Summary: This study investigated the mixing at the southwestern boundary of the Ulleung Basin in the Japan/East Sea using ship-based, moored, and quasi-autonomous observations. The results showed the presence of strong tidal currents, high-frequency internal wave packets, and energetic turbulence over the sill connecting the Korea/Tsushima Strait and the Ulleung Basin. In addition, strong velocity shear associated with the semidiurnal baroclinic tide was found near the bottom.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Oceanography
Samuel M. M. Kelly, Sebastine Ogbuka
Summary: This study shows that the Coastal Trapped Waves (CTWs) modes are orthogonal with respect to energy flux, allowing for precise quantification of energy fluxes and generation in numerical simulations.
JOURNAL OF PHYSICAL OCEANOGRAPHY
(2022)
Article
Mechanics
Nathan E. E. Grube, M. Pino Martin
Summary: Recent direct numerical simulation studies have shown that in highly compressible regime, the amplification of streamwise Reynolds stress in canonical shock-isotropic turbulence interactions (SITIs) is higher than in previous studies. This can be explained by the relatively high Mach number and significant dilatational energy in the incident flow. Loss of amplification is observed as the flow parameters approach the threshold between wrinkled and broken shock regimes due to highly perturbed shock structure. The proposed parametrization based on root-mean-square Mach number fluctuation improves the collapse of shock structure data, suggesting its applicability to general isotropic inflow fields.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Physics, Fluids & Plasmas
E. J. Kolmes, N. J. Fisch
Summary: Diffusive operations can transform an initial state into different states, releasing energy as free energy. In continuous systems, the accessible ground-state energy has an upper bound corresponding to a specific distribution pattern.
Article
Oceanography
Mark E. Inall, Matthew Toberman, Jeff A. Polton, Matthew R. Palmer, J. A. Mattias Green, Tom P. Rippeth
Summary: The study found a robust positive relationship between the model-derived barotropic to baroclinic conversion and the observed pycnocline integrated epsilon. A fitted power law relationship of approximately one-third was discovered, providing a simple new parameterization. The research also discussed reasons for this apparent power law and where the missing dissipation may be occurring.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2021)
Article
Oceanography
A. P. Zulberti, N. L. Jones, M. D. Rayson, G. N. Ivey
Summary: This study presents observations of the mean and turbulent field of a bottom mixing-layer at a gently sloping continental shelf site influenced by tides and nonlinear internal waves. The study finds that the thickness of the mixing-layer varies at both semidiurnal and sub-tidal frequencies, with an average thickness of around 10 meters. The compression and expansion of the mixing-layer by internal tides and nonlinear internal waves affects the mean velocity profiles.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Geosciences, Multidisciplinary
Xavier Crosta, Johan Etourneau, Lisa C. Orme, Quentin Dalaiden, Philippine Campagne, Didier Swingedouw, Hugues Goosse, Guillaume Masse, Arto Miettinen, Robert M. McKay, Robert B. Dunbar, Carlota Escutia, Minoru Ikehara
Summary: Antarctic sea ice has become more extensive in the past four decades despite a warming climate. Regional climate heterogeneity in Indian Antarctic sea-ice cover over the last 2000 years is driven by multi-decadal variability of El Nino Southern Oscillation and Southern Annular Mode. Natural variability plays a crucial role in recent sea-ice trends and decadal variability in the Southern Ocean.
Article
Environmental Sciences
Katie St John Glew, Boris Espinasse, Brian P. Hunt, Evgeny A. Pakhomov, Sarah J. Bury, Matt Pinkerton, Scott D. Nodder, Andres Gutierrez-Rodriguez, Karl Safi, Julie C. S. Brown, Laura Graham, Robert B. Dunbar, David A. Mucciarone, Sarah Magozzi, Chris Somes, Clive N. Trueman
Summary: Polar marine ecosystems are vulnerable to climate change effects, requiring new approaches to understand spatiotemporal interactions in the Southern Ocean food webs. Isoscapes of carbon and nitrogen are useful in identifying spatial variation and interpreting stable isotope compositions in animal studies.
GLOBAL BIOGEOCHEMICAL CYCLES
(2021)
Article
Geosciences, Multidisciplinary
Katelyn M. Johnson, Robert M. McKay, Johan Etourneau, Francisco J. Jimenez-Espejo, Anya Albot, Christina R. Riesselman, Nancy A. N. Bertler, Huw J. Horgan, Xavier Crosta, James Bendle, Kate E. Ashley, Masako Yamane, Yusuke Yokoyama, Stephen F. Pekar, Carlota Escutia, Robert B. Dunbar
Summary: The study used ancient sediment cores to investigate the impacts of Antarctic sea ice and subdecadal climate variability on phytoplankton bloom frequency, revealing that intensified coastal sea ice can reduce the frequency of bloom events.
Article
Limnology
Sarah B. Traiger, Brian Cohn, Demetra Panos, Margaret Daly, Heidi K. Hirsh, Maria Martone, Isabella Gutierrez, David A. Mucciarone, Yuichiro Takeshita, Stephen G. Monismith, Robert B. Dunbar, Kerry J. Nickols
Summary: Research indicates that canopy-forming giant kelp can locally increase dissolved oxygen and pH in coastal ecosystems through photosynthesis. However, the limited spatial extent and magnitude of this effect suggest that kelp forests may have limited potential to mitigate acidification and hypoxia.
LIMNOLOGY AND OCEANOGRAPHY
(2022)
Article
Ecology
Margaret A. McManus, Adam T. Greer, Amanda H. Timmerman, Jeff C. Sevadjian, C. Brock Woodson, Robert Cowen, Derek A. Fong, Stephen Monismith, Olivia M. Cheriton
Summary: Plankton distribution in the ocean is patchy, with thin layers being a typical oceanographic feature. Research showed that particle aggregates in and outside the thin layer have different properties, suggesting passive accumulation of particles within the layer.
MARINE ECOLOGY PROGRESS SERIES
(2021)
Review
Environmental Sciences
Kyle C. Cavanaugh, Tom Bell, Maycira Costa, Norah E. Eddy, Lianna Gendall, Mary G. Gleason, Margot Hessing-Lewis, Rebecca Martone, Meredith McPherson, Ondine Pontier, Luba Reshitnyk, Rodrigo Beas-Luna, Mark Carr, Jennifer E. Caselle, Katherine C. Cavanaugh, Rebecca Flores Miller, Sara Hamilton, Walter N. Heady, Heidi K. Hirsh, Rietta Hohman, Lynn Chi Lee, Julio Lorda, James Ray, Daniel C. Reed, Vienna R. Saccomanno, Sarah B. Schroeder
Summary: Surface-canopy forming kelps are crucial for ecosystems, but are under threat from global and local pressures. Remote sensing data is a valuable tool for monitoring kelp forests, but must be carefully selected and tailored to management objectives and regional characteristics. Integration of different datasets and approaches is important for promoting coordination of management strategies.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Limnology
Grace Chang, Galen Egan, Joseph D. McNeil, Samuel McWilliams, Craig Jones, Frank Spada, Stephen Monismith, Oliver Fringer
Summary: The study shows that near-bed physical forcing and particle responses vary by season, with the most prominent effects observed in summer and winter. Specific tau(char) values have been identified as driving changes in particle characteristics during different seasons, suggesting the importance of parameterizing tau(char) in sediment transport models.
LIMNOLOGY AND OCEANOGRAPHY LETTERS
(2022)
Article
Environmental Sciences
Arnoldo Valle-Levinson, Margaret A. Daly, Braulio Juarez, Leonardo Tenorio-Fernandez, Matheus Fagundes, C. Brock Woodson, Stephen G. Monismith
Summary: This study reveals how kelp forests can influence the physical processes in coastal ocean environments. Specifically, it shows how kelp forests can suppress the typical upward movement of cool subsurface waters around headlands. This suppression is achieved through a process known as "flow ducting," where coastal flows are concentrated through kelp gaps and kept away from the morphological influences of headlands. This flow ducting is similar to the tortuous flow through porous media.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Geography, Physical
Alexis Vizcaino, Francisco J. Jimenez-Espejo, Robert B. Dunbar, David Mucciarone, Antonio Garcia-Alix, Ina Neugebauer, Daniel Ariztegui
Summary: This study examines past wind variability in Tierra del Fuego, Argentina, which intersects the core of the Southern Hemisphere Westerly Winds. The analysis of a piston core from Bahia Grande reveals periodic changes in oxygen concentration, which are attributed to variations in the Southern Hemisphere Westerly Winds. Additionally, an intensification of El Nino/Southern Oscillation activity is observed during the past 2,000 years.
Article
Environmental Sciences
Margaux Steyaert, Mathilde Lindhart, Alexandra Khrizman, Robert B. Dunbar, Michael B. Bonsall, David A. Mucciarone, Emma Ransome, Nadia Santodomingo, Paige Winslade, Catherine E. I. Head
Summary: This study assesses the composition and diversity patterns of cryptobenthic organisms in remote tropical reef sites and examines the influence of local abiotic factors. The study finds distinct environmental profiles between sampling sites and identifies significant correlations between environmental parameters and the abundance of different organisms. The findings highlight the importance of understanding the relationship between reef communities and environmental factors for reef conservation and management.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Geography, Physical
Bethany C. Behrens, Yusuke Yokoyama, Yosuke Miyairi, Adam D. Sproson, Masako Yamane, Francisco J. Jimenez-Espejo, Robert M. McKay, Katelyn M. Johnson, Carlota Escutia, Robert B. Dunbar
Summary: The Adelie Basin provides an ideal location to study regional changes in ice sheet and ocean dynamics through examination of sediment deposits. The (Be-10/Be-9)(reac) ratio can provide insights into changes in freshwater input, primary productivity, and scavenging efficiency, but additional factors need to be considered when using it as a proxy for ice shelf cover and glacial dynamics.
QUATERNARY SCIENCE ADVANCES
(2022)
Review
Ecology
Melissa Ward, Tye L. Kindinger, Heidi K. Hirsh, Tessa M. Hill, Brittany M. Jellison, Sarah Lummis, Emily B. Rivest, George G. Waldbusser, Brian Gaylord, Kristy J. Kroeker
Summary: This study synthesizes the results from 56 studies on seagrass meadow metabolism and highlights the spatial and temporal variability in oxygen fluxes. The study finds that daytime net community production is generally positive and similar across seasons and geographies. The study also observes positive correlations between gross primary production and temperature, but these effects may vary between temperate and tropical ecosystems.
Article
Environmental Sciences
Aaron L. Strong, Matthew M. Mills, Ivy B. Huang, Gert L. van Dijken, Sara E. Driscoll, G. Mine Berg, Raphael M. Kudela, Stephen G. Monismith, Christopher A. Francis, Kevin R. Arrigo
Summary: Research shows that high NH4+ loading is not the driver of lower productivity in the San Francisco Bay Delta. Although phytoplankton preferred NH4+ to NO3- in the experiment, the form of dissolved inorganic nitrogen had no effect on growth rates or species composition. Light levels had the greatest impact on chlorophyll a accumulation and phytoplankton growth rates.
ELEMENTA-SCIENCE OF THE ANTHROPOCENE
(2021)
