Code for tracer ventilation analysis in the Cape Basin
This repository contains the analysis code used in:
Koets, R., Swart, S., Donohue, K., & du Plessis, M. (2026) Observations of tracer ventilation in the Cape Basin, Agulhas Current Retroflection Ocean Science.
The code supports the analysis of high-resolution glider observations used to investigate ventilation, mixing, and mesoscale–submesoscale dynamics in the Cape Basin.
Code DOI
The archived version of this repository is available at:
DOI: DOI: 10.5281/zenodo.18215721
Please cite this DOI when using or adapting the code.
Repository Structure
The notebooks are intended to be run in the order listed below.
- Quality Control
QC.ipynb Performs quality control on raw glider data, including filtering, despiking, and removal of unreliable measurements.
- Sensor Calibration
calibration_ctd.ipynb Calibrates glider oxygen measurements using a ship-based CTD cast.
- Gridding
Gridding.ipynb Interpolates calibrated glider data onto regular depth–time grids for further analysis.
- Instabilities and Geostrophic Velocities
Instabilities_geostrophicVel.ipynb Computes geostrophic velocities and analyses mesoscale and submesoscale instabilities.
- Finite-Size Lyapunov Exponents (FSLE)
create_fsle/ Scripts used to generate the FSLE dataset from velocity fields.
fsle.ipynb Analysis and visualization of FSLE fields to quantify horizontal stirring and strain.
- Vertical Velocities
vertical_velocity.ipynb Analysis of vertical velocities. Results from this notebook are presented in the Supplement of the paper.
- Figures
combined_figures.ipynb Generates the combined figures shown in the main manuscript.