Repository for dipole reversal study.

Contents

• Models (all spherical harmonic models used)
  • IGRF
  • IMMAB4
  • CHAOS5
  • CALS10K1B
• instantaneous_flows (original study by Sam/Phil)
  • original code (original fortran code files provided by Phil)
  • modified code (modified fortran code to be called by python)
  • functions.py (module containing required functions)
  • igrf.ipynb (IGRF analysis)
  • immab4.iypnb (IMMAB4 analysis)
  • IMM_roc.txt (data file from analysis output)
  • IMM_roc_ex.txt (data file from analysis output)

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Instantaneous flows

Flows are optimised for the instantaneous Rate Of Change (ROC) of the axial dipole (g10). ROC is calculated for unconstrained and for purely toroidal flows given a magnetic field and an RMS flow velocity.

Using the code

To compile the fortran code (requires fftw3):

1. First navigate to instantaneous_flows/modified_code and change the path to the fftw3 library within the Makefile to your own location, then run the Makefile with make.

To setup the python environment:

1. To create the conda environment for the python code, run conda env create -f environment.yml from within instantaneous_flows
2. Activate the conda environment with source activate dipole_reversal
3. Finally add the kernel to those available to jupyter notebooks with python -m ipykernel install --user --name dipole_reversal --display-name "Python (dipole_reversal)"
4. The jupyter notebooks can now be run with jupyter notebook (you may need to select the kernel you have just installed)

foe-linux users

You may find that an old (and bugged) version of cartopy exists in your python path (it loaded into mine automatically) and get an import error message when creating the maps. In instantaneous_flows/functions.py edit the line: sys.path.insert(0,'~/anaconda3/envs/dipole_reversal/lib/python3.7/site-packages') changing the path to the location of your anaconda environments if not at the above path. This ensures the correct paths are searched first.

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