Cracking the Code of Pre-Earthquake Signals

Friedemann Freund at

Our Earth is a restless planet. Occasionally – quite often, in some regions of the world – the restlessness turns deadly. Of all natural hazards, earthquakes are the most feared. They are feared because they seem to strike so unpredictably. Yet, for centuries, and even millennia, people living in seismically active regions have noted premonitory signals. The historical records talk of changes of the water level in wells, of strange weather, of ground-hugging fog, of unusual behavior of animals (both domestic and wild) that seem to feel the approach of a major earthquake. With the advent of modern science and technology the list of premonitory signals has become even longer. Among them are

  1. Sporadic emissions of low to ultralow-frequency electromagnetic radiation from the ground
  2. Occasional local magnetic field anomalies reaching a strength of half a percent of the Earth’s main dipole field
  3. Changes in the lower atmosphere that are accompanied by the formation of haze and a reduction of moisture in the air
  4. Large patches, often tens to hundreds of thousands of square kilometers in size, seen in night-time infrared satellite images where the land surface temperature seems to fluctuate rapidly
  5. Passing perturbations in the ionosphere at 90 – 120 km altitude that affect the transmission of radio waves

More here.