A5052699558- Oceanographic and Atmospheric Processes
- Climate variability and models
- Geology and Paleoclimatology Research
- Marine and coastal ecosystems
- Tropical and Extratropical Cyclones Research
- Geological Studies and Exploration
- Meteorological Phenomena and Simulations
- Ocean Waves and Remote Sensing
- Geological formations and processes
- Geological and Geophysical Studies
- Methane Hydrates and Related Phenomena
- Microplastics and Plastic Pollution
- Marine and fisheries research
- Marine Biology and Ecology Research
- Atmospheric and Environmental Gas Dynamics
- Seismic Imaging and Inversion Techniques
- Marine and Offshore Engineering Studies
- Recycling and Waste Management Techniques
- Energy Load and Power Forecasting
- Advanced Differential Geometry Research
- Geometric Analysis and Curvature Flows
- Quantum Computing Algorithms and Architecture
- Coastal and Marine Management
- Quantum chaos and dynamical systems
- Arctic and Antarctic ice dynamics
Japan Agency for Marine-Earth Science and Technology
2015-2024
Defence Electronics Application Laboratory
2018
University of Hawaiʻi at Mānoa
2007-2016
University of Hawaii System
2007-2016
Pacific International Center for High Technology Research
2007-2016
Ajanta Pharma (India)
2016
The University of Tokyo
1996-2005
In the Indian Ocean, mid-depth oxygen minimum zones (OMZs) occur in Arabian Sea and Bay of Bengal. The lower part Arabian-Sea OMZ (ASOMZ; below 400 m) intensifies northward across basin; contrast, its upper (above is located central/eastern basin, well east most productive regions along western boundary. Bay-of-Bengal (BBOMZ), although strong, weaker than ASOMZ. To investigate processes that maintain Indian-Ocean OMZs, we obtain a suite solutions to coupled biological/physical model. Its...
Abstract. Over the past decade, our understanding of Indian Ocean has advanced through concerted efforts toward measuring ocean circulation and air–sea exchanges, detecting changes in water masses, linking physical processes to ecologically important variables. New pathways mechanisms have been discovered that control atmospheric oceanic mean state variability. This review brings together new ocean–atmosphere system since last comprehensive review, describing patterns, interactions, climate...
Abstract The salinity distribution in the South China Sea (SCS) has a pronounced subsurface maximum from 150–220 m throughout year. This feature can only be maintained by existence of mean flow through SCS, consisting net inflow salty North Pacific tropical water Luzon Strait and outflow Mindoro, Karimata, Taiwan Straits. Using an inverse modeling approach, authors show that magnitude space–time variations SCS thermohaline structure, particularly for maximum, allow quantitative estimate...
In this paper, we investigate basic dynamics of the Leeuwin Current (LC) using a dynamically "minimal" model, one that lies at bottom planned hierarchy LC models. The model is steady-state, inviscid, 2-layer system, in which upper-layer density fixed to ρ1(y), all mixing and advection are ignored, β ≠ 0. As result, solutions can be obtained analytically. Our both simplifies extends prior models sort, include drag fundamental way adopt f-plane. Solutions semi-infinite domain, x ≤ xe, y yn,...
Abstract The Leeuwin Current System (LCS) along the coast of Western Australia consists poleward-flowing (LC), equatorward-flowing Undercurrent (LUC), and neighboring flows in south Indian Ocean (SIO). Using geostrophic currents obtained from a highly resolved (⅛°) hydrographic climatology [CSIRO Atlas Regional Seas (CARS)], this study describes spatial structure annual variability LC, LUC, SIO zonal currents, estimates their transports, identifies linkages among them. In CARS, LC is...
Abstract. A quasi-global eddying ocean hindcast simulation using a new version of our model, called OFES2 (Ocean General Circulation Model for the Earth Simulator 2), was conducted to overcome several issues with unrealistic properties in its previous version, OFES. This paper describes model and simulated oceanic fields compared OFES also observed data. includes sea-ice tidal mixing scheme, is forced by newly created surface atmospheric dataset JRA55-do, from 1958 2016. We found...
The size distribution of marine microplastics provides a fundamental data source for understanding the dispersal, break down, and biotic impacts in ocean. observed at sea surface generally shows, from large to small sizes, gradual increase followed by rapid decrease. This decrease has led hypothesis that smallest fragments are selectively removed sinking or biological uptake. Here we propose new model distribution, focusing on fragmentation plastics. is inspired ideas statistical mechanics....
The South China Sea throughflow begins at the Luzon Strait, as an intrusion of Kuroshio. At present time, there are insufficient in situ measurements either to estimate accurately transport loss or provide a clear picture Kuroshio pathway Strait. In this study, we use newly available, multi‐year, high‐resolution satellite images and numerical model track warm, relatively low‐biomass, Pacific water carried by A suite experiments out identify key factors that influence paths can reproduce...
We investigate the sensitivity of numerical-model solutions to regional changes in vertical diffusion. Specifically, we vary background diffusion coefficient, κb, within spatially distinct subregions tropical Pacific, assess impacts those changes, and diagnose processes that account for them. Solutions respond a anomaly, δκb, three ways. Initially, there is fast response (several months), due interaction rapidly-propagating, barotropic gravity waves with eddies other mesoscale features. It...
Abstract The impact of internal tidal mixing on the volume transport Indonesian Throughflow (ITF) is examined by a comparison high‐resolution quasi‐global ocean simulations with and without scheme. ITF found to be increased in presence mixing. This because decreases density within below lower thermocline increases buoyancy water column. As result, surface pressure sea height (SSH) are raised. magnitude SSH increase larger for tropical Pacific Ocean than other basins, possibly many islands...
The Indonesian Throughflow (ITF) carries an annual average of about 15 Sv water from the Pacific through Seas Into Indian Ocean, and its year-to-year variation ranges 1 to 4 Sv. A 10-member ensemble 41-year integrations a semi-global eddy-resolving oceanic general circulation model is examined explore intrinsic (chaotic) variability ITF transport associated flow. It found that annual-mean different by between members at several years. characteristic vertical horizontal structures...
Abstract The Tsuchiya jets (TJs) are narrow eastward currents, located a few degrees on either side of the equator at depths from 200 to 500 m in Pacific Ocean. In this study, non-eddy-resolving, oceanic general circulation models (OGCMs) used investigate dynamics southern TJ. Most solutions found rectangular basin extending 100° zonally and 40°S 10°N. They forced by idealized zonal meridional winds representing trades southerly near South American coast, prescribed interocean (IOC) that...
Historically, a hierarchy of ocean models have been used to investigate the dynamics basin-scale, deep, meridional overturning circulations (MOCs). Near base this are idealized solutions forced only by surface buoyancy flux. Our goal is provide complete dynamical description such "base" solutions, thereby placing on firmer foundation. For purpose, we obtain two types models: variable-density, layer model (VLOM) and an general circulation (COCO), former allowing for nearly analytic latter...
Abstract Sea surface temperature (SST) fronts in mid- to high-latitude oceans have significant impacts on extratropical atmospheric circulations and climate. In the western subarctic Pacific, sharp SST form between cold water recently found quasi-stationary jets that advect warm waters originating Kuroshio northeastward. Here we present a new mechanism of jet formation paying attention propagation baroclinic Rossby waves is deflected by eddy-driven barotropic flows over bottom rises,...
Oceanic alternating zonal jets at depth have been detected ubiquitously in observations and ocean general circulation models (GCMs). Such oceanic are generally considered as being generated by purely processes. Here we explore a possible air‐sea interaction induced surface signatures of the deep using an eddy‐permitting coupled atmosphere‐ocean GCM (CGCM). The 23‐year CGCM integration reproduces bands latitudinally‐narrow Southeast Pacific. They extend from sea to well below main thermocline...
In this study, we use an ocean model to explore how vertical mixing influences temperature in the eastern equatorial Pacific Ocean. Our approach is change background diffusion coefficient from a constant value κb κb+δκ(z) various subregions of tropical Pacific, and then determine resulting changes near-equilibrium response. companion paper (Furue et al., 2015), consider impacts depth-independent anomalies. Here, examine depth-dependent anomalies that are confined above, or centered on,...
Abstract The South China Sea (SCS) is often treated as a semienclosed water body, with the Luzon Strait its only connection to Pacific Ocean. A branch of Kuroshio flows northwestward across enter SCS, carrying North Tropical Water (NPTW) into basin. Using subsurface salinity maximum tracer for NPTW, authors show how important three secondary straits—the Taiwan north and Karimata Mindoro Straits south—are NPTW intrusion at Strait. demonstrate that SCS cannot reach an equilibrium state...
Abstract The Tsuchiya jets (TJs) are narrow eastward currents located along thermal fronts at the poleward edges of thermostad water in Pacific Ocean. In this study, an oceanic general circulation model (OGCM) is used to explore dynamics northern TJ. Solutions found a rectangular basin, extending 100° zonally and from 40°S 40°N. They forced by three idealized forcings: several patches wind fields, including one that simulates strong Ekman pumping region vicinity Costa Rica Dome (CRD);...
Abstract. Over the past decade, our understanding of Indian Ocean has advanced through concerted efforts toward measuring ocean circulation and its water properties, detecting changes in masses, linking physical processes to ecologically important variables. New pathways mechanisms have been discovered, which control atmospheric oceanic mean state variability. This review brings together new ocean-atmosphere system since last comprehensive review, describing patterns, air-sea interactions...
Abstract Previous studies have shown the presence of strong mesoscale eddy activities in Indonesian Seas and their influence on transport water mass properties Throughflow (ITF), a mean flow from Pacific Ocean to Indian through Archipelago. This study explores effects these activities, or high‐frequency variability (HFFV), residence time pathway ITF by conducting Lagrangian particle tracking experiments using velocity field an eddy‐resolving ocean general circulation model. Particles are...
Recently, Schloesser et al. (2012) explored the dynamics of descending branch meridional overturning circulations (MOCs), by obtaining analytic solutions to a variable-density, 2-layer model (VLOM) forced only surface buoyancy flux. Key processes involved are poleward thickening upper layer along eastern boundary due Kelvin-wave adjustments, westward propagation that coastal structure Rossby waves, and their damping mixing; resulting zonal pressure gradient causes MOC converge into northern...