| 1. Domain | 1.1 Scope of the Domain | Boundaries | The range of phenomena the science includes and excludes. | Studies the physical properties, motion, and dynamics of seawater, including currents, waves, tides, mixing, stratification, heat and salt transport, and ocean–atmosphere interactions. Excludes chemical, biological, and geological processes unless they interact with physical dynamics. |
| | Scale | The spatial, temporal, or organizational level at which the science operates (e.g., quantum, cellular, social, cosmic). | Operates from molecular-scale turbulence → small-scale mixing and waves → mesoscale eddies → basin-scale gyres → global thermohaline circulation. Temporal scales range from seconds (wave motions) to millennia (deep-ocean overturning). |
| 1.2 Ontological Commitments | Entities | The kinds of things assumed to exist within the domain (particles, organisms, agents, fields, etc.). | Water masses, currents, waves, eddies, gyres, air–sea interface, density layers, stratification boundaries, turbulence fields, boundary layers, sea ice, heat/salt anomalies, pressure fields, Coriolis field. |
| | Properties | The fundamental attributes these entities possess (mass, charge, genotype, preference, etc.). | Temperature, salinity, density, velocity, shear, turbulence intensity, buoyancy, heat content, salt content, mixed-layer depth, pressure, sea-surface height, viscosity, diffusivity. |
| | Categories | The basic ontological types used to classify domain elements (substances, processes, relations, structures). | Water masses, circulation regimes (wind-driven, thermohaline), wave types (surface gravity waves, internal waves, tsunamis), boundary layers (Ekman, benthic), stratification types (stable/unstable), mixing regimes, climate modes (ENSO, NAO). |
| 1.3 State-Variables | Variables | The measurable or definable properties that describe system conditions. | Temperature, salinity, density, velocity components (u, v, w), sea-surface height, pressure, buoyancy frequency, vorticity, heat/salt fluxes, turbulence parameters, ice cover, internal-wave energy. |
| | Parameterization | How variables encode and represent the system’s state. | States encoded by T–S diagrams, equation of state (ρ = ρ(T, S, p)), velocity profiles, hydrographic sections, heat/salt budgets, streamfunctions, vorticity equations, turbulence closure parameters, gridded ocean fields. |
| 1.4 Admissible Idealizations | Simplifications | Conceptual reductions used to make the domain tractable (point masses, rational agents, perfect gases). | Hydrostatic approximation, Boussinesq approximation, neglecting compressibility, assuming geostrophic balance, ignoring small-scale turbulence, idealized boundary conditions, linear wave theory, constant viscosity/diffusivity. |
| | Validity Conditions | The limits and contexts in which idealizations hold or break down. | Valid for large-scale and moderate-frequency motions; breaks down for strong turbulence, breaking waves, convection, near-surface mixing, bottom boundary layers, nonlinear internal-wave interactions, and small-scale processes. |
| 1.5 Domain Assumptions | Structural Assumptions | Background ontological stances such as determinism, continuity, randomness, discreteness. | Ocean dynamics follow conservation laws (mass, momentum, energy, salt); rotation matters (Coriolis); stratification governs mixing; density gradients drive circulation; surface forcing controls upper-ocean behavior; deep ocean evolves slowly. |
| | Implicit Commitments | Unstated but necessary assumptions that shape the field’s conceptual structure. | Assumes measurable T/S fields, stable water-mass definitions, representable turbulence, reliable tracer conservation, and meaningful scaling from local observations to basin-scale processes. |
| 1.6 Internal Coherence Requirements | Consistency | The demand that domain concepts do not contradict one another. | Requires agreement among observations, circulation models, conservation laws, wave theories, and the equation of state; consistent dynamics across scales and regions. |
| | Compatibility | The requirement that entities, variables, and assumptions fit together into a unified descriptive framework. | Must align with atmospheric science, climate dynamics, geophysics, chemical and biological oceanography, and Earth system models within a unified physical–climate framework. |
| 2. Evidence Layer | 2.1 Observable Phenomena | Observables | The aspects of the domain that can produce detectable signals accessible to measurement. | Sea-surface height, currents, temperature, salinity, density structure, waves, tides, ocean color, mixed-layer depth, internal waves, turbulence, eddies, sea ice extent, heat/salt fluxes, stratification, upwelling/downwelling. |
| | Detection Limits | The boundaries of what can be resolved or sensed by current instruments or methods. | Limited by satellite resolution, depth penetration of acoustic instruments, sensor precision, temporal sampling gaps, biofouling on in situ sensors, inability to observe deep ocean continuously, noise from waves/tides/wind, and sparse spatial coverage. |
| 2.2 Measurement Systems | Units | Standardized quantifications (meters, seconds, volts, decibels, dollars, etc.) necessary for consistent comparison. | Temperature (°C), salinity (psu), velocity (m/s), sea-surface height (cm), density (kg/m³), pressure (dbar), heat flux (W/m²), salt flux (kg/m²/s), wave height/period (m, s), turbulence dissipation (W/kg), ice thickness (m). |
| | Instruments | Devices and tools (microscopes, spectrometers, sensors, surveys, detectors) used to produce measurements. | CTDs, Argo floats, ADCPs, current meters, pressure sensors, satellite altimeters, scatterometers, radiometers, gliders, moorings, drifters, tide gauges, microstructure profilers, wave buoys, ice-profiling sonar, XBTs. |
| 2.3 Operational Definitions | Definitions | Terms defined by specific measurement procedures, ensuring empirical clarity. | Mixed-layer depth defined by density/temperature thresholds; water mass defined by T–S properties; geostrophic current defined by pressure gradients; eddies defined by closed streamlines or SSH anomalies; turbulence defined by dissipation-rate thresholds. |
| | Procedures | The explicit steps required to perform a measurement in a reproducible way. | CTD casts, Argo profiling cycles, ADCP transects, glider missions, satellite calibration and retrieval, mooring maintenance, wave-buoy deployments, microstructure profiling, tide-gauge operation, quality-control and despiking procedures. |
| 2.4 Data Acquisition | Protocols | Formal processes for gathering data under controlled or standardized conditions. | Repeat hydrographic sections, global Argo array sampling, fixed mooring time series, satellite repeat orbits, underway shipboard ADCP, autonomous-vehicle surveys, coordinated multi-platform campaigns, synoptic ocean–atmosphere field programs. |
| | Sampling | Rules determining which subset of the domain is measured and how representative it is. | Vertical profiling, horizontal transects, time-series sampling at daily–hourly frequencies, depth-stratified sampling, regional vs global coverage, density of floats/drifters, repeat sections for decadal change detection. |
| 2.5 Data Character & Format | Data Types | The form raw evidence takes (time series, spectra, images, counts, qualitative records). | Time-series records, profiles, gridded fields, satellite images, velocity sections, T–S diagrams, spectra of waves and turbulence, sea-surface height maps, eddy-tracking datasets, climatologies, reanalysis products. |
| | Resolution | The granularity or precision with which data is captured. | Determined by sensor accuracy, vertical spacing of profiles, satellite spatial footprint, revisit frequency, ADCP bin size, microstructure probe resolution, mooring sampling interval, and filtering applied to remove tides or noise. |
| 2.6 Reliability & Calibration | Calibration | Adjustment procedures ensuring instruments produce accurate results. | CTD laboratory calibration, Argo float calibration, satellite cross-calibration (radiometers, altimeters), ADCP compass/tilt calibration, mooring sensor recalibration, wave-buoy motion correction, ice-sensor offset removal. |
| | Error Characterization | Identification and quantification of noise, uncertainty, bias, and measurement error. | Instrument drift, salinity bottle-sample mismatch, satellite atmospheric interference, wave-noise contamination, mooring motion artifacts, sparse sampling aliasing eddies/tides, microstructure noise, thermal-lag errors, and glider navigation error. |
| 3. Structural Layer | 3.1 Patterns & Regularities | Laws / Relations | Stable, repeatable patterns governing how observables behave across conditions. | Geostrophic balance; Ekman transport; hydrostatic balance; internal-wave dispersion; thermohaline gradients driving overturning. |
| | Invariants | Quantities or properties that remain constant under transformations (symmetries, conservation laws). | Conservation of mass/momentum/heat/salt; stable T–S signatures; consistent stratification; Rossby-parameter dependence; eddy scales ~ Rossby radius. |
| 3.2 Causal Architecture | Mechanisms | Underlying processes or structures that produce the observed regularities. | Wind stress, buoyancy forcing, Coriolis effects, turbulent mixing, convection, internal-wave breaking, eddy interactions, boundary friction. |
| | Pathways | Organized sequences of interactions forming a causal chain or network. | Surface forcing → mixed layer → Ekman flow → geostrophic currents; cooling/salinification → dense-water formation → sinking; internal waves → propagation → breaking → mixing. |
| 3.3 Theoretical Vocabulary | Concepts | Core terms that encode the domain’s structure (force, gene, equilibrium, field). | Stratification, vorticity, Rossby number, Froude number, Ekman layer, gyres, thermocline, pycnocline, mixing efficiency, barotropic/baroclinic modes. |
| | Classifications | Taxonomies, categories, or typologies that organize entities and relations. | Circulation regimes, wave types, instability types, mesoscale/submesoscale eddies, boundary layers, climate modes (ENSO, NAO). |
| 3.4 Formal Representations | Equations | Mathematical constructs expressing laws, relations, or mechanisms. | Boussinesq/hydrostatic momentum equations; continuity; advection-diffusion; geostrophic relation; PV equation; equation of state. |
| | Models | Structured representations—mathematical, computational, or conceptual—used to predict and explain phenomena. | GCMs, regional ocean models, wave models, mixed-layer models, internal-wave models, eddy-resolving simulations, 2-layer/box models. |
| 3.5 Idealized Structures | Simplified Models | Purposeful abstractions that capture essential dynamics while omitting irrelevant detail. | Linear waves, geostrophic-only flow, two-layer oceans, uniform stratification, constant mixing, homogeneous basins, steady winds. |
| | Limit Conditions | Regimes where specific models or approximations hold (classical vs. quantum, linear vs. nonlinear). | Fail under strong turbulence, convection, nonlinear eddy dynamics, coastal complexity, internal-wave breaking, rapid wind variability. |
| 3.6 Integrative Frameworks | Unifying Theories | Higher-order structures that connect disparate laws or mechanisms under a coherent whole. | Links turbulence → eddies → gyres → global overturning → climate system via fluid dynamics, thermodynamics, and rotation. |
| | Interdisciplinary Links | Points where the theory connects to adjacent sciences or larger explanatory systems. | Connects to atmospheric dynamics, climate science, geophysics, biogeochemistry, glaciology, and planetary-ocean studies. |
| 4. Method Layer | 4.1 Inquiry Design | Experimental Design | Structured plans for manipulating variables to test causal claims. | Control of wind forcing, heat/salt fluxes, wave generation, tank geometry, stratification, and Coriolis effects in rotating tanks, wave flumes, and turbulence labs to test hypotheses about ocean circulation, mixing, and wave dynamics. |
| | Observational Design | Systematic approaches for gathering non-manipulated data (surveys, field studies, natural experiments). | Systematic monitoring of natural currents, temperature/salinity structure, internal waves, tides, stratification, turbulence, and sea-surface height via satellite, moorings, floats, drifters, and shipboard surveys without artificial perturbation. |
| 4.2 Testing & Validation | Hypothesis Testing | Procedures for evaluating whether evidence supports or contradicts specific claims. | Comparison of predicted circulation patterns, heat/salt budgets, wave spectra, mixing rates, eddy behavior, and stratification changes with observations from CTDs, ADCPs, microstructure profilers, drifters, and satellite data. |
| | Replication | The requirement that results be independently reproducible under similar conditions. | Repeated hydrographic sections, repeated mooring deployments, multiple glider missions, repeated ADCP transects, replicated internal-wave experiments, repeated satellite passes, and reprocessed datasets across analysts. |
| 4.3 Inference & Evaluation | Statistical Inference | Rules for drawing conclusions from noisy or incomplete data. | Estimation of uncertainties in velocity, T/S profiles, heat/salt fluxes, eddy scales, turbulence dissipation, wave spectra, and sea-surface height; filtering, regression, EOF analysis, spectral analysis, and uncertainty propagation. |
| | Model Comparison | Criteria (fit, simplicity, predictive accuracy, robustness) used to evaluate competing models. | Evaluation of competing GCMs, regional models, wave models, turbulence closures, mixing schemes, and assimilation frameworks on fit, predictive accuracy, robustness, and physical realism. |
| 4.4 Error Management | Error Analysis | Identification and quantification of random and systematic errors. | Identification of instrument drift, salinity bottle mismatch, satellite atmospheric contamination, ADCP side-lobe interference, mooring motion artifacts, aliasing of tides/eddies, navigation errors, and microstructure noise. |
| | Bias Control | Methods for minimizing subjective, instrumental, or procedural biases. | Cross-calibration of sensors, randomized survey routes when feasible, independent QC of CTD/ADCP data, blind reprocessing, standardized despiking/quality control, removal of tidal and inertial biases, consistent mapping procedures. |
| 4.5 Adjudication & Revision | Peer Scrutiny | Collective evaluation of claims through critique, review, and debate. | Independent review of circulation reconstructions, turbulent-mixing estimates, wave analyses, model tuning choices, assimilation settings, and interpretation of satellite-derived climatologies. |
| | Theory Revision | Procedures for modifying, replacing, or discarding models based on new evidence. | Updating mixing schemes, revising parameterizations, adjusting energy budgets, correcting stratification models, refining wave–current interaction theories, and incorporating contradictory observational evidence. |
| 4.6 Integrity Conditions | Transparency | Requirements to disclose methods, data, assumptions, and limitations. | Full disclosure of sensor calibration, processing steps, filtering methods, model assumptions, grid spacing, parameterizations, QC thresholds, observational uncertainties, and conditions of data omission. |
| | Ethical Standards | Norms ensuring responsible conduct in experimentation, data handling, and publication. | Safe ocean operations, adherence to research-permit rules, nondestructive sampling principles, responsible instrument deployment, accurate attribution of datasets, and honest reporting of uncertainty and limitations. |