Article
Engineering, Marine
Ke Qu, Jia Men, Xu Wang, Xiaohan Li
Summary: This study analyzes the transformation and breaking process of crest- and trough-focused wave groups on fringing reefs using the nonhydrostatic numerical flow solver (NHWAVE). The results show that there are complex interactions between the fringing reef and the focused wave group, with high intensity breaking waves forming at the reef crest. Additionally, the local wave height can be effectively reduced due to wave breakings at the reef crest and bottom friction of the reef flat. The findings of this study will enhance understanding of the wave hydrodynamics of extreme waves over fringing reefs.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Oceanography
Mark L. Buckley, Ryan J. Lowe, Jeff E. Hansen, Ap R. van Dongeren, Andrew Pomeroy, Curt D. Storlazzi, Dirk P. Rijnsdorp, Renan F. da Silva, Stephanie Contardo, Rebecca H. Green
Summary: Wave breaking on steep fore-reef slopes can dissipate incident waves, but wave setup and infragravity waves contribute to wave-driven water levels. Laboratory experiments and numerical models show that fore-reef slope controls wave runup on reef-fronted beaches, while beach slope controls wave runup on plane beaches. The presence of tall roughness elements on reef flats can significantly reduce wave runup.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Engineering, Marine
L. Guo, K. Qu, J. X. Huang, X. H. Li
Summary: This study investigates the impacts of offshore wind on the hydrodynamics of solitary waves on fringing reefs. The research results show that offshore wind can significantly increase the maximum wave runup height and decrease the wave reflection coefficient.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Engineering, Marine
K. Qu, J. X. Huang, Y. Yao, L. Guo, X. Wang, X. H. Li, C. B. Jiang
Summary: In recent years, excavating materials from the reef flat has become the main source of sand and aggregate for coral-lined coasts in tropical and subtropical regions, particularly low-lying atoll islands. However, the effects of excavation pits on the wave hydrodynamics and runup processes of tsunami-like waves over fringing reefs have been understudied. This study systematically investigates these effects using a high-resolution two-phase flow model and finds that excavation pits have noticeable influences on wave transformation and runup processes. The complex interactions between the breaking surge bore and the water body in the pit dissipate more wave energy and result in a lower maximum wave runup height, though local wave heights near the pit can be amplified.
Article
Engineering, Marine
Tao Yuan, Yu Yao, Zhuangzhi Li, Conghao Xu
Summary: This study aims to investigate the characteristics of wave-driven currents across coral reefs through experiments and numerical modeling. The experimental results reveal the impact of waves on the water flow, while the numerical simulations provide insights into the vertical profiles and variations of the flow along the reef.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Engineering, Ocean
Ruili Fu, Yuxiang Ma, Guohai Dong
Summary: The study shows that the wave-induced set-up and wave-driven currents increase significantly with higher significant wave height and seaward depth. The skewness and kurtosis of horizontal velocities and surface elevations also vary more significantly as the seaward depth increases, with the maximum values located downstream compared to surface elevations.
APPLIED OCEAN RESEARCH
(2021)
Article
Engineering, Ocean
Yu Yao, Xianjin Chen, Conghao Xu, Meijun Jia, Changbo Jiang
Summary: In this study, a 3D numerical model based on a numerical wave tank was developed to investigate the interaction between waves and coral reef profiles. The model was validated through laboratory experiments and used to analyze the impacts of forcing conditions, reef morphology, and reef roughness on wave transformation and runup. An empirical formula for predicting wave runup was derived from the numerical results. The study also examined the cross-reef variations of energy dissipation, wave spectrum, wave shape parameters, nonlinearity parameter, TKE, and its dissipation rate for both smooth and rough reefs.
APPLIED OCEAN RESEARCH
(2022)
Article
Engineering, Marine
Curt D. Storlazzi, Annouk E. Rey, Ap R. van Dongeren
Summary: Many populated, tropical coastlines with fringing coral reefs are at risk of wave-driven marine flooding, which is attributed to shore-normal channels. Understanding the influence of these channels on runup and flooding is crucial for predicting high runup events along the coastline.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Engineering, Marine
K. Qu, T. W. Liu, L. Chen, Y. Yao, S. Kraatz, J. X. Huang, G. Y. Lan, C. B. Jiang
Summary: This paper investigates the hydrodynamic characteristics of the transformation and runup processes of tsunami-like wave impinging on a permeable fringing reef. It discusses the effects of factors such as wave height, water depth, and properties of the permeable layer of the reef on the hydrodynamic characteristics. The study finds that the protective function of fringing reefs may be grossly underestimated when using the classical quadratic friction law.
Article
Engineering, Marine
Gancheng Zhu, Bing Ren, Ping Dong, Guoyu Wang, Weidong Chen
Summary: The laboratory investigation revealed that the infragravity wave height and water level on the reef flat are significantly larger in the fringing reef system compared to the platform reef system. This difference is attributed to the superposition of incoming and reflected infragravity waves, as well as enhanced wave energy transfer from shorter waves to infragravity waves due to more violent wave breaking in the surf zone.
Article
Engineering, Ocean
Yu Yao, Xiaoxiao Yang, Weijie Liu, Tiancheng He
Summary: The study investigates the impact of different surface roughness on wave characteristics, finding that reef roughness affects parameters such as breaker type, surf zone width, and breaker depth. By improving existing empirical formulas, the accuracy of the model is enhanced, and it is found that the bottom friction coefficient in the model aligns with field observations.
MARINE GEORESOURCES & GEOTECHNOLOGY
(2021)
Article
Geosciences, Multidisciplinary
Yu Yao, Xiaoxiao Yang, Sai Hin Lai, Ren Jie Chin
Summary: This study introduces an alternative machine learning technique based on MLP-NN for predicting tsunami-like solitary wave run-up over fringing reefs. The MLP-NN with one hidden layer and ten hidden neurons provides the best predictions for wave run-up. Model performance is evaluated by analyzing prediction errors and conducting a mean impact value analysis.
Article
Engineering, Marine
Li Xiao, Kezhao Fang, Minghan Huang, Dongxu Wang, Zhongbo Liu
Summary: This paper presents flume experiments and numerical simulations of focused wave group propagation over an idealized fringing reef profile and its impact on the vertical wall mounted on reef flat. The results show that the low frequency wave motion contributes significantly to the total force exerted on the wall. The geometry characters of fringing reef and focusing position also have an effect on the maximum horizontal force on the vertical wall.
Article
Engineering, Marine
Xu Wang, Ke Qu, Jia Men, Liangbin Zhang, Junjie Li, Rongze Gao
Summary: Dredging materials from reef flats is important for meeting the infrastructure needs of coral-lined shores, but it can have profound influences on coral ecological stability and the hydrodynamic characteristics of coral reefs. A study using a numerical wave solver analyzed the wave propagation, transformation, setup, and runup processes on fringing reefs with artificial pits. The presence of artificial pits can slightly decrease wave height and reduce wave runup at the backreef slope. When placed close to the reef edge, artificial pits can have noticeable effects on wave setup along the reef flat.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Oceanography
Samantha A. Maticka, Justin S. Rogers, Clifton B. Woodson, Benjamin B. Hefner, Stephen G. Monismith
Summary: This study discusses the wave-forced flows in the reef system on Ofu, American Samoa, which are influenced by tidal variations. At high tide, the balance between the free-surface pressure gradient and the radiation stress gradient generates undertows and alongshore flows, similar to rip currents observed on beaches. At low tides, the wave forcing drives purely onshore flows. Wave transport plays a significant role in determining the total net transport, with the strongest flows occurring at high tides and when the wave forcing is strongest.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Limnology
Derek C. Roberts, Galen C. Egan, Alexander L. Forrest, John L. Largier, Fabian A. Bombardelli, Bernard E. Laval, Stephen G. Monismith, Geoffrey Schladow
Summary: Strong and sustained winds can drive dramatic hydrodynamic responses in density-stratified lakes, impacting water quality, ecosystem function, and stratification. Analytical expressions offer insight into lake dynamics during severe wind events, but predicting the aggregate response of a natural system to complex hydrodynamic phenomena can be challenging. Study on Lake Tahoe during strong wind events reveals complex rotational and non-rotational upwelling setups, highlighting the importance of understanding the role of upwelling events in lake ecosystems.
LIMNOLOGY AND OCEANOGRAPHY
(2021)
Article
Oceanography
Galen Egan, Grace Chang, Samuel McWilliams, Gene Revelas, Oliver Fringer, Stephen Monismith
Summary: This study conducted field work on the shoals of South San Francisco Bay to elucidate the mechanisms driving cohesive sediment erosion. The research found a strong correlation between wave shear stress and turbulent sediment fluxes, as well as explored the impact of tidal turbulence on sediment transport. Despite the dominance of waves in eroding sediment, there was favorable agreement between in situ boundary layer erosion measurements and laboratory erosion measurements.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2021)
Article
Geosciences, Multidisciplinary
Marianne Cowherd, Galen Egan, Stephen Monismith, Oliver Fringer
Summary: In this study, near-bed velocity profiles were measured in South San Francisco Bay with high temporal and spatial resolution. Through Hilbert analysis, wave phase-dependent boundary layer thickness was calculated and compared to boundary layer thickness-based eddy viscosity derived from mixing length relationships. The analysis showed a finite-time response between turbulence dissipation and boundary layer thickness, with the latter lagging behind the former based on turbulence response timescale estimates.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Mechanics
Sorush Omidvar, Mohammadreza Davoodi, C. Brock Woodson
Summary: Internal wave generation involves the conversion of uniform barotropic energy into varying baroclinic energy due to vertical acceleration, resulting in a phase lag between density perturbations and velocity. The use of a time-varying background density allows for a more accurate understanding of the dynamics of barotropic to baroclinic conversion. Tidal averaging and modal decomposition methods are consistent in isolating topographic energy conversion but do not provide insights into the temporal and depth aspects of conversion.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Oceanography
M. Lindhart, J. S. Rogers, S. A. Maticka, C. B. Woodson, S. G. Monismith
Summary: This study explores a framework for classifying reefs as open or closed based on their dynamics, using observations, numerical models, and theory. By observing reefs in American Samoa, the study shows that reefs exhibit different dynamic regimes under tidal and wave forcing, transitioning between open and closed behavior over a tidal cycle. The results suggest that classifying reefs based on their dynamics, rather than geometry, is a more meaningful approach to predicting their dynamical response to wave and tidal forcing.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2021)
Article
Limnology
Robin Guillaume-Castel, Gareth J. Williams, Justin S. Rogers, Jamison M. Gove, J. A. Mattias Green
Summary: Upwelling has significant impacts on tropical ecosystems nearshore, and a novel method using Temperature Stratification Index (TSI) is presented to automatically detect cold-water intrusions caused by upwelling in tropical waters, removing biases associated with user-defined parameters and automatically determining the directional origin of the cold-water mass.
LIMNOLOGY AND OCEANOGRAPHY-METHODS
(2021)
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
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
Meteorology & Atmospheric Sciences
Xuanting Hao, Jie Wu, Justin S. Rogers, Oliver B. Fringer, Lian Shen
Summary: In this study, a new method is proposed to simulate the interaction between complex surface waves and large amplitude internal solitary waves. The model is based on a high-order spectral method and an internal wave solver, and it has been validated through convergence tests and simulations of different scenarios.
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
Ecology
Alexandra Smith, Juan Domingo Aguilar, Charles Boch, Giulio De Leo, Arturo Hernandez-Velasco, Stephanie Houck, Ramon Martinez, Stephen Monismith, Jorge Torre, C. Brock Woodson, Fiorenza Micheli
Summary: This study documents the mass mortality events of abalone in Baja California Sur, Mexico in 2009-2010 and the subsequent rapid recovery of the population. It highlights the effectiveness of a combination of resilience strategies, including marine reserves, fishing closures, and ecological monitoring. The close collaboration between fishers, resource managers, scientists, and NGOs is crucial for designing and implementing successful conservation and management interventions.
Article
Oceanography
Sorush Omidvar, Matheus Fagundes, C. Brock Woodson
Summary: This study fills the gap in previous research on the interaction between tides and winds by including the K-1 tide and shoreward diurnal sea breeze in the model. The results show that the interaction between the K-1 tide and M-2 is constructive and insensitive to the initial phase lag, and wind enhances M-2 conversion.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Oceanography
Justin S. Rogers, Frederick T. Mayer, Kristen A. Davis, Oliver B. Fringer
Summary: This study presents a modeling study of internal tides propagating around an idealized island. It shows that subcritical slope has the greatest potential for creating favorable conditions for benthic organisms through enhanced upwelling. These findings are important for understanding the propagation of internal waves and the characteristics of water flow around islands.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Oceanography
Samantha A. Maticka, Justin S. Rogers, Clifton B. Woodson, Benjamin B. Hefner, Stephen G. Monismith
Summary: This study discusses the wave-forced flows in the reef system on Ofu, American Samoa, which are influenced by tidal variations. At high tide, the balance between the free-surface pressure gradient and the radiation stress gradient generates undertows and alongshore flows, similar to rip currents observed on beaches. At low tides, the wave forcing drives purely onshore flows. Wave transport plays a significant role in determining the total net transport, with the strongest flows occurring at high tides and when the wave forcing is strongest.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)