loading page

WALDO! A Massive Public Repository of Global ELF/VLF Radio Data
  • +1
  • Morris Cohen,
  • Mark Golkowski,
  • Umran Inan,
  • John DeSilva
Morris Cohen
Georgia Institute of Technology Main Campus

Corresponding Author:[email protected]

Author Profile
Mark Golkowski
University of Colorado Denver
Author Profile
Umran Inan
Koç University
Author Profile
John DeSilva
Stanford University
Author Profile


Observations of radio waves in the Extremely Low Frequency and Very Low Frequency band (ELF/VLF, 0.3-30 kHz) have a host of geophysical uses, including lightning detection and characterization, D-region ionosphere remote sensing, detection of solar flares and geomagnetic storms, gravity waves, gamma-ray burst detection, observations of whistlers, chorus and hiss, to infer wave-particle interactions in the magnetosphere, plasmaspheric state. It’s been looked at for earthquake forecasting and also has commercial uses like submarine communications and subterranean prospecting. For many years ELF/VLF data have been collected at various locations and by various groups around the world for a variety of scientific purposes, but most of this data is not available publicly. We introduce the World Archive of Low-frequency Data and Observations (WALDO), a repository of ELF/VLF data from recordings taken over the past two decades by Stanford University and subsequently by Georgia Tech and University of Colorado Denver. The locations of the recordings are all around the world, including Alaska, Antarctica, Australia, and many low and mid latitude stations. Some sites were more consistent than others but there’s a lot of untapped value in this dataset. Funding for these recordings came from many years of funding from NSF, NASA, DoD, and others, on various basic science projects, and we feel a responsibility to make sure the datasets are now preserved. We are in the process of transferring many 100s of TBs of data and sharing every raw bit for anyone to download and analyze. This includes both “broadband” data that includes the entire spectrum from 500 Hz – 50 kHz, and “narrowband” data corresponding to amplitudes and phases of specific transmitting beacons. We are also including automatically generated summary plots, and a host of basic analysis tools to allow anyone to download and analyze the data. We will announce and present WALDO, update its status and timeline for full deployment, and detail some of the uses of ELF/VLF data, with the goal of enabling its use by anyone interested. We will not be finished by the Fall meeting (ripping 80,000 DVDs can take a while) but whatever we finished will be public and hopefully we will be far along by then. Finally, we will have the answer to the age-old question…”Where’s WALDO?”