dringeis / mitgcm

M.I.T General Circulation Model master code and documentation repository

• 👋 Hi, I’m @dringeis Damien `Dami' Ringeisen
• 👀 I’m interested in physics applied to climate models, specially in the cryosphere 🧊
• 🌱 I’m currently learning FORTRAN, Machine Learning and many other!
• 💞️ I’m looking to collaborate on sea ice rheological models with machine learning and ice-sheet and climate coupling
• 📫 How to reach me: email me [email protected]

mitgcm's Issues

Velocity anomalies in sea ice model at low convergence requirements

From observations in #2

There are large velocity differences in sea ice simulations with different numerical convergence conditions.

ToDo:

• Do simulations for different convergence conditions and see if there is a convergence of velocities to the correct values
• Same but for 36km
• See what we get out of it and write a small report

Implement different Mohr-Coulomb yield curves in MITgcm

Implement and test new formulations of yield curves in MITgcm.

• Mohr-Coulomb yield curve as Ip et al (1991) implemented it.
• Mohr-Coulomb yield curve with elliptical plastic potential
• Mohr-Coulomb yield curve with elliptical plastic potential, derived with a different method
• Mohr-Coulomb yield curve with Teardrop plastic potential
• Mohr-Coulomb yield curve with Parabolic lens plastic potential
• Test all these rheologies for numerical convergence
• Test all these rheologies for the failure angles

Sharp corners problems at the ice-land-open water in compression

There are allegedly weird velocity solutions in the VP sea ice model at the corner of an interface ice-land-open water in uni-axial compression; James Williams, personal communication.

Tasks:

• Plot the problem with the elliptical yield curve (velocity, deformation, and residual).
  • Velocity
  • Deformation
  • Residual
  • Plot the ArkawaC grid velocity
• Explain the inversed velocities
  • Test in a free drift set-up if the velocity inversion also happens
  • Test with more LSR iterations if the problem persists (numerical convergence problem
• Ideas for after:
• Test if a smooth ice-open water border would solve the alleged problem.
• Test if the smooth border solution changes the failure angles.
• Implement the smooth ice-open water in the other rheological uniaxial compression experiments if it works.
• If it does not work, try a free drift shore condition.

Implement and test the Inexact Newton Method in MITgcm

Coding a way to improve convergence with the LSR solver.

Implementation in branch https://github.com/dringeis/MITgcm/tree/INM