GO-ABOVE the Geospace Observatory - Array for
Broadband Observations of VLF/ELF Emissions, is a ground‐based
array of VLF radio receivers located across Canada and run as a
part of the Canadian Space Agency's Geospace Observatory
(GO). The ABOVE instruments monitor electromagnetic waves in a
frequency range from 100 Hz to 75 kHz, covering chorus and hiss
emissions as well as U.S. Navy transmitters near 25 kHz.

  The summary plots span 1 second long and are taken 5 minutes apart
  from multiple stations in the GO-ABOVE array. Each plot contains 4
  dynamic spectrograms, two for the North-South antennas and two for
  the East-West antennas. For each pair one spectrogram spans a
  frequency range of 100 Hz to 10 kHz while the other spans from 100
  Hz to 75 kHz. Following the four dynamic spectrograms are two
  amplitude vs. time plots for the North-South and East-West
  antennas.
  
  A directory tree structure allows access to these files. Each station
  has a separate directory below the year, month and day. Within some of
  the month directories is a data availability chart.