Analysis of satellite data shows that the earth sends out certain signals in the days before a large earthquake strikes.
According to a press release from M.I.T., just before the Magnitude 9 earthquake struck Japan,
the total electron content of the ionosphere increased dramatically over the epicenter, reaching a maximum three days before the quake struck.
At the same time, satellite observations showed a big increase in infrared emissions from above the epicenter [see graphic below], which peaked in the hours before the quake. In other words, the atmosphere was heating up.
These kinds of observations are consistent with an idea called the Lithosphere-Atmosphere-Ionosphere Coupling mechanism. The thinking is that in the days before an earthquake, the great stresses in a fault, as it is about to give, cause the release of large amounts of radon.
The radioactivity from this gas ionizes the air on a large scale and this has a number of [specific] effects. Since water molecules are attracted to ions in the air, ionization triggers the large scale condensation of water. But the process of condensation also releases heat and it is this that causes infrared emissions.
A similar phenomenon was noticed just before the Haitian earthquake. These atmospheric phenomena may explain why animals seem to act strangely prior to an earthquake. Perhaps they can sense the changes.
Read the full analysis here. The graphic below shows infrared emissions in the days preceding the Japanese earthquake.