Notebook: DAS for Oceanographic applications

Open this Colab notebook to replicate the exercises presented in the video tutorial.

This notebook explores Distributed Acoustic Sensing (DAS) data from the GeoLab fibre on Madeira Island. It demonstrates how to read, visualise, and analyse DAS files. Key steps include:

• Data loading and preparation: Downloading a pre-processed DAS HDF5 file (downsampled to 2Hz) and loading it into a NumPy array.
• Time-series analysis: Plotting single channel time-series to observe raw data.
• Frequency domain analysis: Generating spectrograms and magnitude spectra for individual channels.
• Spatial and temporal visualisation: Plotting time-space diagrams (plotTimeSpace and plotSpaceTime) to visualize data across channels and time.
• Frequency-Wavenumber (F-K) analysis: Calculating and plotting F-K spectra to identify wave propagation characteristics, including the overlay of theoretical ocean surface gravity wave (OSGW) dispersion curves.
• Noise identification: Calculating and plotting the standard deviation per channel to identify potentially noisy channels.

The notebook also provides context on wave types in the ocean and their typical frequency ranges, and explores channel segmentation based on bathymetric profiles.