Seismology is the exact science of the mechanical processes in the Earth’s interior. All conclusions made by seismologists are based on the analysis of data obtained using high-tech modern equipment. This information is used to compile earthquake catalogs, maps of seismic activity and alert the population of the regions about the onset of seismic events.
Since seismology operates only with scientifically confirmed data, scientists can make:
- long-term earthquake forecasting based on the collection of historical data from earlier seismic events. These forecasts allow seismologists to draw conclusions about the periodicity of earthquakes from a few to hundreds of years;
- medium – term forecasts predict earthquakes in period ranging from several months to tens of years. This type of forecasting relies on characteristics of regional seismic regime and conducting statistical analysis of predictive indicators.
Unfortunately, modern science cannot make a short-term earthquake forecast by reporting the seismic event a day or several hours in advance. The onset of an earthquake, its magnitude and the epicenter are recorded by instruments after the fault starts to move.
Short-term earthquake forecast from seismologists
Since seismology does not have accurate information about the connection between earthquake precursors and seismic activity, seismologists rely only on scientific data obtained with the help of tools and instruments. Why does science ignore such well-known signs of an approaching earthquake, such as changes in animal behavior, electric field indicators or a series of weak tremors? Such events may occur before an earthquake or may be absent. Therefore, precursors cannot indicate with complete certainty an impending earthquake.
Based on exact data obtained from instruments measuring wave processes in the Earth’s crust or ocean, seismology can warn of the earthquake’s initiation when activity is detected in a tectonic fault. Since earthquakes and tsunamis are wave-based phenomena, the detection of ground and water oscillations, measurement of their intensity and precise location of the epicenter enable scientists to make short-term forecasts. While earthquake waves reach the surface, there is a short period (a few seconds to a minute) to warn of an impending event. This technology is used in early warning systems about an earthquake or the tsunami threat.
What safety measures can be taken a few seconds before an earthquake
Early warning systems can reduce the effects of a strong earthquake only if the administration and the residents of the region take protective measures. Recipients of the warning must understand that an earthquake is imminent, and everything must be done within a short time to minimize the risk of seismic hazards. What can be done within a few seconds after receiving the notification? Possible measures include:
- opening garage doors of fire stations and emergency services;
- stopping the traffic on bridges and in tunnels;
- shutting off valves on gas and oil pipelines;
- redirecting planes to land and stopping trains;
- stopping elevators on the nearest floor and opening doors;
- shutting down operations at factories and plants;
- activating automated systems for emergency shutdown of processes at critical infrastructure facilities.
Receiving a warning means you need to find a safe place inside or outside, take shelter and prepare for earthquake.
What is the difference between a prediction and a warning
In case of receiving information from a seismic early warning center, it should be remembered that the risk of seismic events is inevitable. If you have been notified of an earthquake and tsunami, you should not waste time thinking about the possibility of avoiding danger. Unlike predictions indicating the risk of seismic activity in the region, the warning system is activated only after the onset of an earthquake recorded by special equipment. If you live in a high-risk seismic region and want to have more time to respond, pay attention to the precursors and use effective mobile applications that can give the most accurate forecast.