Chimney-like intense pelagic upwelling in the center of basin-scale cyclonic gyres in large Lake Geneva DOI Open Access
Seyed Mahmood Hamze‐Ziabari, Ulrich Lemmin, Mehrshad Foroughan

et al.

Authorea (Authorea), Journal Year: 2022, Volume and Issue: unknown

Published: Dec. 21, 2022

Basin-scale quasi-geostrophic gyres are common features of large lakes subject to Coriolis force. Cyclonic often characterized by dome-shaped thermoclines that form due pelagic upwelling which takes place in their center. At present, dynamics the Surface Mixed Layer (SML) oceans and poorly documented. A unique combination high-resolution 3D numerical modeling, satellite imagery field observations allowed confirming for first time a lake, existence intense center cyclonic under strong shallow (summer) weak deep (winter) stratified conditions/thermocline. Field Lake Geneva revealed surprisingly from thermocline SML even lake surface occurred as chimney-like structures cold water within SML, confirmed Advanced Very High-Resolution Radiometer data. Results calibrated model suggest classical Ekman pumping mechanism cannot explain such upwelling. Analysis contribution various terms vertically-averaged momentum equation showed nonlinear (advective) term dominates, resulting heterogeneous divergent flows gyres. The flow ageostrophic strain caused gyre distortion is responsible SML. potential impact on long-term at measurement station suggests caution should be exercised when relying limited (in space and/or time) profile measurements monitoring quantifying processes lakes.

Language: Английский

The Influence of Horizontal Dispersion on Residence Times in Shallow Lakes DOI Creative Commons
Eiji Masunaga, Oliver B. Fringer,

Tatsumi KITAMURA

et al.

Water Resources Research, Journal Year: 2025, Volume and Issue: 61(2)

Published: Feb. 1, 2025

Abstract This study presents results of circulation and residence time in lakes influenced by wind‐induced mixing investigated with numerical simulations. The area is Lake Kasumigaura, a continuous lake system primally consisting two lakes, West North Lake. Although metrological conditions depths are similar for both the surface shape very different. A model resolves primary features wind‐driven forced observed river discharges wind stress. passive tracer released from mouths used to estimate evaluate processes. Wind‐driven flow dominates kinetic energy induces chaotic motions leading dispersion which largely lakes. Results indicate that much longer well‐mixed middle basin than estimated horizontal diffusivity approximately three times larger large small‐narrow suggests predominantly driven influences circulation, water exchange processes

Language: Английский

Citations

0
Validity of theoretical solutions for a rotating rectangular basin with two-layer stratification due to a suddenly imposed wind DOI Creative Commons
Hiroki Matsumoto, Keisuke Nakayama

Physics of Fluids, Journal Year: 2025, Volume and Issue: 37(3)

Published: March 1, 2025

In 1974, Csanady and Scott developed theoretical solutions for the flow fields displacements of a density interface in rectangular basin with two-layer stratification when constant wind stress was suddenly imposed. However, their do not satisfy all boundary conditions. present study, we have corrected these analyzed validity by comparing them numerical simulations. We found that high upwelling does occur nonlinear effects, vertical circulation, layer effects are small. addition, Wedderburn number WN is more significant applicability than Burger Si. Furthermore, highly applicable to actual phenomena WN≥ 1.98.

Language: Английский

Citations

0
Chimney‐Like Intense Pelagic Upwelling in the Center of Basin‐Scale Cyclonic Gyres in Large Lake Geneva DOI Creative Commons
Seyed Mahmood Hamze‐Ziabari, Ulrich Lemmin, Mehrshad Foroughan

et al.

Journal of Geophysical Research Oceans, Journal Year: 2023, Volume and Issue: 128(7)

Published: July 1, 2023

Abstract Basin‐scale quasi‐geostrophic gyres are common features of large lakes subject to Coriolis force. Cyclonic often characterized by dome‐shaped thermoclines that form due pelagic upwelling takes place in their center. At present, the dynamics within surface mixed layer (SML) poorly documented. A unique combination high‐resolution 3D numerical modeling, satellite imagery and field observations allowed confirming, for first time a lake, existence intense center cyclonic under strong shallow (summer) weak deep (winter) stratified conditions/thermocline. Field Lake Geneva revealed surprisingly from thermocline SML even lake occurred as chimney‐like structures cold water SML, confirmed Advanced Very High‐Resolution Radiometer data. Results calibrated model suggest classical Ekman pumping mechanism cannot explain such upwelling. Analysis contribution various terms vertically averaged momentum equation showed nonlinear (advective) term dominates, resulting heterogeneous divergent flows gyres. The flow ageostrophic strain caused gyre distortion is responsible SML. potential impact on long‐term at measurement station suggests caution should be exercised when relying limited (in space and/or time) profile measurements monitoring quantifying processes lakes.

Language: Английский

Citations

2
Boat effects on lake water clarity and the efficacy of a no-wake zone policy DOI Creative Commons
Sergio A. Valbuena, Geoffrey Schladow, Fabián A. Bombardelli

et al.

Lake and Reservoir Management, Journal Year: 2024, Volume and Issue: unknown, P. 1 - 18

Published: Sept. 24, 2024

Language: Английский

Citations

0
Factors influencing summer phytoplankton biomass in a large river system with impoundments: retention time, zooplankton grazing, thermal stratification and internal seiching in a hydro lake DOI
Max M. Gibbs,

Eddie J. Bowman,

Karl Safi

et al.

New Zealand Journal of Marine and Freshwater Research, Journal Year: 2023, Volume and Issue: 58(2), P. 195 - 218

Published: Feb. 12, 2023

Phytoplankton production as indicated by chlorophyll a concentrations in Lake Karāpiro, the last hydro power station lake on Waikato River, shows high seasonal variability but long term trend of decrease, despite an abundance nutrients (N and P) river. Early studies pre-2005 river system's eight dams identified that only Lakes Ohakuri Arapuni thermally stratified summer, it was hypothesised thermal stratification could enhance phytoplankton productivity through increased retention time. During. more recent study (2013–2014), Karāpiro also found to be with thermocline around depth intake. In this we enhanced growth confining them well-lit epilimnion. However, limited nutrient supply became depleted zooplankton grazing adversely impact biomass, highest pressure spring lowest late summer autumn, consistent increase concentration. We wind stress along axis can induce internal seiche, which causes substantial stepwise change water quality downstream sweeps up down across

Language: Английский

Citations

1
Physical mechanisms of internal seiche attenuation for non-ideal stratification and basin topography DOI
Rafael de Carvalho Bueno, Tobias Bleninger, Bertram Boehrer

et al.

Environmental Fluid Mechanics, Journal Year: 2023, Volume and Issue: 23(3), P. 689 - 710

Published: May 8, 2023

Language: Английский

Citations

0
Fast Prediction of Solute Concentration Field in Rotationally Influenced Fluids Using a Parameter-Based Field Reconstruction Convolutional Neural Network DOI Open Access
Xiaohui Yan, Abdolmajid Mohammadian,

Huijuan Yu

et al.

Water, Journal Year: 2023, Volume and Issue: 15(13), P. 2451 - 2451

Published: July 3, 2023

Many high-performance fluid dynamic models do not consider fluids in a rotating environment and often require significant amount of computational time. The current study proposes novel parameter-based field reconstruction convolutional neural network (PFR-CNN) approach to model the solute concentration rotationally influenced fluids. A new three-dimensional (3D) numerical solver, TwoLiquidMixingCoriolisFoam, was implemented within framework OpenFOAM simulate effluents subjected influence rotation. Subsequently, developed solver employed conduct experiments generate data. PFR-CNN designed predict fields neutrally buoyant water bodies based on Froude number (Fr) Rossby (Ro). proposed trained validated with train-validation dataset. predicted for two additional tests demonstrated good performance approach, algorithm performed better than traditional approaches. This offers 3D can transport effects rotation few seconds, significantly reduce costs. advance ability flow processes, CNN-based potentially be spatial distribution any physical variable lentic, ocean, earth system.

Language: Английский

Citations

0
Chimney-like intense pelagic upwelling in the center of basin-scale cyclonic gyres in large Lake Geneva DOI Open Access
Seyed Mahmood Hamze‐Ziabari, Ulrich Lemmin, Mehrshad Foroughan

et al.

Authorea (Authorea), Journal Year: 2022, Volume and Issue: unknown

Published: Dec. 21, 2022

Basin-scale quasi-geostrophic gyres are common features of large lakes subject to Coriolis force. Cyclonic often characterized by dome-shaped thermoclines that form due pelagic upwelling which takes place in their center. At present, dynamics the Surface Mixed Layer (SML) oceans and poorly documented. A unique combination high-resolution 3D numerical modeling, satellite imagery field observations allowed confirming for first time a lake, existence intense center cyclonic under strong shallow (summer) weak deep (winter) stratified conditions/thermocline. Field Lake Geneva revealed surprisingly from thermocline SML even lake surface occurred as chimney-like structures cold water within SML, confirmed Advanced Very High-Resolution Radiometer data. Results calibrated model suggest classical Ekman pumping mechanism cannot explain such upwelling. Analysis contribution various terms vertically-averaged momentum equation showed nonlinear (advective) term dominates, resulting heterogeneous divergent flows gyres. The flow ageostrophic strain caused gyre distortion is responsible SML. potential impact on long-term at measurement station suggests caution should be exercised when relying limited (in space and/or time) profile measurements monitoring quantifying processes lakes.

Language: Английский

Citations

0