About two minutes before an 8.2-degree earthquake lashed several Mexican cities on Thursday night, the loudspeakers of the seismic alert were activated allowing millions of people to evacuate their homes and find shelter in a safe place.
The Mexican Seismic Alert System (Sasmex) has installed 97 sensors that permanently monitor earth movements throughout the country.
When one of these sensors detects important earthquakes, it emits a radio signal at least 50 seconds in advance, which is transmitted by radio stations, television stations, mobile applications or by the 10 thousand loudspeakers that are in Mexico City.
Given the effectiveness of this alarm, the question that arises is whether a similar system could work Costa Rica.
According to the National Seismological Network (RSN), Costa Rica has automatic earthquake detection and location systems in real time, however, being a smaller country, the system would not be as useful.
The waves of the Chiapas earthquake (Mw 8,2) were perceived in Mexico DF about a minute and a half after the alarm was triggered. However, the first waves of the 2012 Sámara earthquake (Mw 7,6) arrived in San José in less than 30 seconds, having traveled 170 km from the epicenter,”
Therefore, experts believe that short distances hinder the effectiveness of a seismic warning system because they allow just a few seconds for automatic systems to detect the earthquake, locate it, calculate its magnitude and send the alert.