Chile, one of the most seismically active countries in the world, has been struck by three major earthquakes of magnitude 8 or greater in the past five years. The first, in February 2010, killed 525 people, including those who died in the tsunami it spawned. But only 11 people have so far been reported killed in the latest, which struck on Wednesday.
Why is the toll so much lower this time?
The latest earthquake was not as powerful.
Though the earthquake on Wednesday was quite strong, at magnitude 8.3, it released only about a third of the energy of the magnitude 8.8 quake in 2010, one of the strongest recorded in modern times. (Magnitude is measured on a logarithmic scale.)
It affected a more focused area.
The 2010 quake struck off the central coast and directly affected large cities and populous areas, including resort areas crowded with vacationers. At least one-third of the country’s coastline suffered significant damage from the tsunami it created, and more minor damage was reported as far away as San Diego and Tokyo. Almost all of Chile lost power. By contrast, the latest quake and its tsunami have mainly affected a single, less densely populated region, Coquimbo.
Coastal residents were better prepared.
Since the 2010 quake, there have been many earthquake drills and dry runs, and evacuation routes have been clearly marked up and down the coast. As a result, though the latest quake’s tsunami did extensive physical damage in several coastal cities and ports, very few people were in harm’s way when the waves hit. In 2014, when a magnitude-8.2 quake struck off northern Chile, Coastal areas were evacuated quickly and efficiently.
Warnings were issued promptly.
In 2010, no tsunami alert was issued, and national leaders prematurely told the public that they could return to their homes. Residents in coastal areas knew to head for higher ground, but many visitors did not. Since then, the government has issued immediate preventive tsunami warnings and has been much more cautious about sounding the all-clear, as seen in the 2014 quake and again this week.
Strong building codes are enforced.
In poorer, developing countries like Haiti or Nepal, major quakes are often devastatingly deadly, with thousands of people killed by collapsing buildings, bridges and dams. It used to be that way in Chile, too, but decades of prosperity have raised construction standards, and the country has learned through hard experience to set and enforce stringent building and safety codes along the lines of those used in California. Because of this, Chile’s modern buildings tend to fare well in quakes, though historic structures and those in rural areas may still be vulnerable.
Emergency response has been improved.
Since 2010, the National Seismic Center in Chile has been operating around the clock, as have many of the regional offices of the government’s national emergency bureau. More robust sea-level monitoring systems and better procedures to help coordinate the efforts of public and private agencies have also made a difference.