A5089840443- Oceanographic and Atmospheric Processes
- Climate variability and models
- Geology and Paleoclimatology Research
- Marine and coastal ecosystems
- Methane Hydrates and Related Phenomena
- Arctic and Antarctic ice dynamics
- Meteorological Phenomena and Simulations
- Geological formations and processes
- Hydrological Forecasting Using AI
- Cryospheric studies and observations
- Ocean Waves and Remote Sensing
- Atmospheric and Environmental Gas Dynamics
- Tropical and Extratropical Cyclones Research
- Ocean Acidification Effects and Responses
- Wind and Air Flow Studies
- Computational Physics and Python Applications
- Scientific Computing and Data Management
- Paleontology and Stratigraphy of Fossils
- Geophysics and Gravity Measurements
- Geological Studies and Exploration
- Computational Fluid Dynamics and Aerodynamics
- Reservoir Engineering and Simulation Methods
- Energy Load and Power Forecasting
- Fluid Dynamics and Vibration Analysis
- Geological Modeling and Analysis
British Antarctic Survey
2015-2024
Hohai University
2018-2019
University of East Anglia
2019
University of Southampton
2019
University of Oxford
2010-2018
Maxwell Institute for Mathematical Sciences
2018
University of Edinburgh
2018
Natural Environment Research Council
2015
Georgia Institute of Technology
2015
Colorado State University
2015
Abstract This study uses a sector configuration of an ocean general circulation model to examine the sensitivity circumpolar transport and meridional overturning changes in Southern Ocean wind stress global diapycnal mixing. At eddy-permitting, finer, resolution, forcing magnitude is drastically reduced. sufficiently high there little or no stress, even limit wind. In contrast, continues vary with but reduced stress. Both continue diffusivity at all resolutions. The becomes less sensitive...
Drake Passage is the narrowest constriction of Antarctic Circumpolar Current (ACC) in Southern Ocean, with implications for global ocean circulation and climate. We review long‐term sustained monitoring programs that have been conducted at Passage, dating back to early part twentieth century. Attention drawn numerous breakthroughs made from these programs, including (1) first determinations complex ACC structure quantifications its transport; (2) realization transport remarkably steady over...
Abstract The Antarctic Circumpolar Current is the strongest current in ocean and has a pivotal impact on stratification, heat content, carbon content. circumpolar volume transport relatively insensitive to surface wind forcing models that resolve turbulent eddies, process termed “eddy saturation.” Here simple model presented explains physics of eddy saturation with three ingredients: momentum budget, relation between form stress energy, an energy budget. both insensitivity increase stress....
Declining atmospheric CO2 concentrations are considered the primary driver for Cenozoic Greenhouse-Icehouse transition, ~34 million years ago. A role tectonically opening Southern Ocean gateways, initiating onset of a thermally isolating Antarctic Circumpolar Current, has been disputed as ocean models have not reproduced expected heat transport to coast. Here we use high-resolution simulations with detailed paleobathymetry demonstrate that tectonics did play fundamental in reorganising...
Abstract The global stratification and circulation, as well their sensitivities to changes in forcing, depend crucially on the representation of mesoscale eddy field a numerical ocean circulation model. Here, geometrically informed energetically constrained parameterization framework for eddies—termed Geometry Energetics Ocean Mesoscale Eddies Their Rectified Impact Climate (GEOMETRIC)—is proposed implemented three-dimensional channel sector models. GEOMETRIC closes buoyancy fluxes according...
The Southern Ocean (SO) surface westerly wind stress plays a fundamental role in driving the Antarctic Circumpolar Current and global meridional overturning circulation. Here, authors investigate contributions of atmospheric fluctuations to mean, variability, trend SO over last four decades using NCEP reanalysis ERA-Interim products. Including variability at synoptic frequencies (2–8 days) higher calculation is found increase strength mean by almost 40% both southern annular mode index be...
The strength of the Antarctic Circumpolar Current (ACC) is believed to depend on westerly wind stress blowing over Southern Ocean, although exact relationship between winds and circumpolar transport yet be determined. Here we show, based theoretical arguments a hierarchy numerical modeling experiments, that global pycnocline depth baroclinic ACC are set by an integral measure path ACC, taking into account its northward deflection. Our results assume mesoscale eddy diffusivity independent...
Abstract An idealized numerical ocean model is used to investigate the sensitivity of partial pressure atmospheric carbon dioxide (pCO 2 ) changes in surface wind stress when mesoscale eddies are permitted flow. When increases, pCO_2 and vice versa. The introduction reduces overall pCO by changing storage due saturation state dioxide, net air‐sea disequilibrium, soft tissue carbon, carbonate pump. However, a full pump decomposition shows different responses for terms. For example,...
Ocean mixing around Antarctica exerts key influences on glacier dynamics and ice shelf retreats, sea ice, marine productivity, thus affecting global level climate. The conventional paradigm is that this dominated by winds, tides, buoyancy forcing. Direct observations from the Antarctic Peninsula demonstrate calving triggers internal tsunamis, breaking of which drives vigorous mixing. Being widespread frequent, these tsunamis are at least comparable to much more important than in driving...
The North Atlantic Ocean contributes approximately 30% of the global ocean carbon uptake. This region plays a vital role in anthropogenic uptake and hosts significant natural cycle driven by physical biogeochemical processes. study focuses on understanding inter-annual variability air-sea CO2 fluxes, storage, Gulf Stream transporting water masses with low concentrations into subpolar Atlantic. We present development application our forward adjoint biogeochemistry models within Estimating...
The physical circulation and biogeochemistry of the Southern Ocean has proved crucial to understanding sensitivity global climate. ventilation deep water, rich in carbon nutrients throughout subpolar is usually framed terms residual overturning. This places emphasis on up- down-welling different water masses. However, for Weddell Gyre it been proposed that casting cycle horizontal gyre may be more informative (MacGilchrist et al., 2019). emphasises role remineralisation at mid-depth organic...
We introduce a new framework for systematically exploring the largest storm surge heights that tropical cyclone in given climate can create. calculate potential intensity and size from model projections find both these limits increase response to change. then use Bayesian optimization with barotropic ocean circulation maximum height reach limits. The key methodological advances of this paper are (i) calculation recently proposed cyclone, now under change (ii) using those constraints, (iii)...
Abstract The date of inception the Antarctic Circumpolar Current is debated due to uncertainty in relative opening times Drake Passage and Tasman Seaway. Using an idealized eddy‐resolving numerical ocean model, we investigate whether both gateways have be open allow for a substantial circumpolar current. We find that overlapping continental barriers do not impede transport excess 50Sv, as long path can traced around barriers. However, presence does lead increased sensitivity current's volume...
ABSTRACT Open-ocean polynyas in the Weddell Sea of Antarctica are product deep convection, which transports Warm Deep Water (WDW) to surface and melts sea ice or prevents its formation. These occur only rarely observational record but a near-permanent feature many climate ocean simulations. A question not previously considered is degree polynya affects nearby Filchner–Ronne Ice Shelf (FRIS) cavity. Here we assess these effects using regional model simulations FRIS, where convection imposed...
Abstract In the Southern Ocean Antarctic Circumpolar Current is significantly steered by large topographic features, and subpolar gyres form in their lee. The geometry of features highly variable, but influence this variation on large-scale flow poorly understood. Using idealized barotropic simulations a zonal channel with meridional ridge, it found that ridge important for determining net volume transport. A relationship observed between width transport determined stress generated ridge....
The Southern Ocean plays a pivotal role in climate change by exchanging heat and carbon, provides the primary window for global deep ocean to communicate with atmosphere. There has been widespread focus on explaining atmospheric CO2 changes terms of wind forcing Ocean. Here, we develop dynamically-motivated metric, residual upwelling, that measures effect dynamics centennial millennial timescales determining communication ocean. metric encapsulates combined, net winds air–sea buoyancy both...
[1] We show that diapycnal mixing can drive a significant Antarctic Circumpolar Current (ACC) volume transport, even when the is located remotely in northern-hemisphere ocean basins. In case of remote forcing, globally-averaged coefficient important parameter. This result anticipated from theoretical arguments and demonstrated global circulation model. The impact enhanced on ACC during glacial periods discussed.
Abstract Including the ocean surface current in calculation of wind stress is known to damp mesoscale eddies through a negative power input and have potential ramifications for eddy longevity. Here, we study spindown baroclinic anticyclonic subject absolute (no current) relative (including forcing by employing an idealized high-resolution numerical model. Results from this demonstrate that dissipates mean kinetic energy (MKE) also generates additional vertical motions throughout whole water...
The response of the major ocean currents to changes in wind stress forcing is investigated with a series idealized, but eddy-permitting, model simulations. Previously, ostensibly similar models have shown considerable variation oceanic changing forcing. Here, it that reason for these differences sensitivity subtle modification idealized bathymetry. key bathymetric parameter extent which strong eddy field generated circumpolar current can interact bottom water formation process. addition an...
Abstract Observed and predicted increases in Southern Ocean winds are thought to upwell deep ocean carbon increase atmospheric CO 2 . However, dynamics affect biogeochemistry circulation pathways on a global scale. Using idealized Massachusetts Institute of Technology General Circulation Model (MITgcm) simulations, we demonstrate that an reduces the sink North Atlantic subpolar gyre. The due reduction is shown be same magnitude as outgassing. mechanism can described follows: leads upper...
Abstract. The early Cenozoic opening of the Tasmanian Gateway (TG) and Drake Passage (DP), alongside synergistic action westerly winds, led to a Southern Ocean transition from large, subpolar gyres onset Antarctic Circumpolar Current (ACC). However, impact changing latitudinal position strength wind stress in altering circulation has been poorly addressed. Here, we use an eddy-permitting ocean model (0.25∘) with realistic late Eocene paleo-bathymetry investigate sensitivity paleo-latitudinal...