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Showing 1441–1470 of 1709 reference entries

Earth & cosmosReactive geochemical transport and activity models

Reactive transport couples species fluxes to kinetic/equilibrium reactions while enforcing elemental and charge balance.

Method
Earth & cosmosUnsaturated flow, constitutive curves and coupling

Richards flow conserves water in a variably saturated porous medium while Darcy flux uses saturation-dependent permeability.

Method
Earth & cosmosGroundwater and poroelastic effective stress

Coupled groundwater and deformation models account for pore pressure, body forces, elastic response and boundary conditions.

Method
Earth & cosmosCoupled incision and sediment conservation

Shared stream-power models combine detachment and transport limits instead of identifying sediment flux with erosion.

Method
Earth & cosmosIce enthalpy and thermal-rheological coupling

Ice thermal models combine advection, diffusion and deformation heating; enthalpy tracks sensible heat and liquid fraction at the pressure-melting boundary.

Method
Earth & cosmosCrack geometry, stress intensity and energy release

Mode-I stress intensity depends on load and crack geometry.

Method
Earth & cosmosRate-and-state friction and fault stability

Rate-and-state friction distinguishes instantaneous velocity response from state evolution.

Method
Earth & cosmosMantle forward models and adjoint sensitivity

Mantle reconstruction solves mass, momentum and energy equations with rheology and thermal boundaries, then uses observations to constrain a past state.

Method
Earth & cosmosIce loading, mantle rheology and glacial isostatic adjustment

Glacial isostatic adjustment jointly depends on ice/ocean loading history and Earth's elastic-viscous response.

Method
Earth & cosmosCore dynamo equations and parameter extrapolation

Rotating dynamo models couple magnetic induction, momentum, heat/composition transport and solenoidal constraints.

Method
Earth & cosmosDynamo power budgets and competing scaling laws

A statistically steady dynamo with no net mechanical or Poynting power through its boundary balances supplied buoyancy power against ohmic and viscous dissipation.

Method
Earth & cosmosEarth-system ensembles and experimental design

Earth-system simulations couple atmosphere, ocean, land, cryosphere and biogeochemistry.

Method
Earth & cosmosPaleoclimate proxy assimilation and withheld validation

Paleoclimate reconstruction combines proxy calibration/age support with a climate-model prior.

Method
Earth & cosmosPrecambrian plate circuits and observation-constrained alternatives

Deep-time full-plate reconstructions combine paleomagnetism, geological ties and evolving topological boundaries.

Method
Earth & cosmos2026 study: automatic viscoelastic Earth adjoints

Scott et al. extended G-ADOPT to elastic-compressible, laterally variable and non-Maxwell viscoelastic models.

Method
Earth & cosmos2026 preprint: GPU mantle-convection benchmarks

The TERRA-NG v1.0 preprint reports a matrix-free GPU Stokes–energy solver specialized for spherical wedges and tests against a spherical-shell convection benchmark.

Method
Earth & cosmosKepler ellipse timing and anomaly conventions

An elliptic two-body ephemeris solves Kepler's equation for eccentric anomaly at a declared time origin, then transforms orbital-plane coordinates to the observing frame.

Method
Earth & cosmosSafeguarded Kepler root solving and observation uncertainty

For an elliptic orbit, d(E-e sin E)/dE is positive, so the root is unique for a chosen unwrapped mean anomaly.

Method
Earth & cosmosProjected baseline, delay and complex visibility

A far-field source produces a geometric delay b·s/c between two antennas.

Method
Earth & cosmosVisibility sampling, smearing and calibration

An interferometer measures a finite set of Fourier samples, leaving unmeasured sky modes.

Method
Earth & cosmosCollisionless phase-space transport

A collisionless distribution follows Hamiltonian trajectories in a mean gravitational potential.

Method
Earth & cosmosSpherical Jeans equation and anisotropy

The stationary spherical nonrotating Jeans moment equation connects tracer density and radial velocity dispersion to enclosed mass through velocity anisotropy.

Method
Earth & cosmosLine-of-sight Jeans projection and boundary closure

A projected dispersion averages line-of-sight moments through the tracer system.

Method
Earth & cosmosStellar structure as a coupled boundary problem

Discretize stellar structure, transport and composition into a residual vector F(y).

Method
Earth & cosmosEOS interpolation, atmosphere matching and model domains

A stellar or planetary EOS can blend differently valid microscopic models.

Method
Earth & cosmosPlane-parallel transfer moments and angular closure

Angle-dependent radiative transfer yields moments J,H,K; flux is 4πH.

Method
Earth & cosmosStatistical equilibrium beyond LTE

NonLTE level populations solve coupled radiative and collisional rate equations with particle/charge constraints and the transfer solution.

Method
Earth & cosmosRotating stellar grids and convection uncertainty

Shellular stellar evolution approximates angular velocity as nearly constant on isobars and models vertical transport and mass loss with prescriptions.

Method
Earth & cosmosIdeal magnetic-fluid induction and divergence

Ideal conducting-fluid motion evolves magnetic flux by induction and preserves an initially solenoidal field.

Method
Earth & cosmosMagnetic stress, tension and Alfvén response

Magnetic pressure and tension contribute a stress tensor whose divergence gives the Lorentz force in the stated quasistatic limit.

Method
MethodSource checked

Ice enthalpy and thermal-rheological coupling

Earth & cosmos

Research context

research method · conditional · As of 2026-10-10

Ice thermal models combine advection, diffusion and deformation heating; enthalpy tracks sensible heat and liquid fraction at the pressure-melting boundary.

Key knowledge

Ice thermal models combine advection, diffusion and deformation heating; enthalpy tracks sensible heat and liquid fraction at the pressure-melting boundary. Surface temperature, basal heat/melt conditions and inflow temperatures close the boundary problem, and thermal changes alter rheology.

Conditions and scope

  • Cold-ice temperature and temperate-ice enthalpy formulations have different basal treatment.
  • Track energy residuals, water fraction and stabilization errors; an imposed basal geothermal flux is uncertain input.
Sources · 1

References

Sources retain their recorded scope. A source link alone does not establish verification of every statement.

  1. ISSM thermal modelNASA/JPL and ISSM developersReference guideissm.jpl.nasa.govRead source

Evidence and review

ISSM thermal model: Internal-energy balance, enthalpy, surface/basal/inflow boundaries (selected source body inspected).

2026-10-10 · Bounded source check of the recorded statement and conditions. This does not certify a unique physical model, reproduce the cited study or replace independent branch review.

Entry detailsPermanent link to this entry ↗
Record identity
research-earth-ice-enthalpy
Revision
research.1
Structured reference record
Postgraduate & research reference