2011: costliest ever year for earthquakes, weather-related disasters
quake, however, triggered a terrible tsunami. The wave devastated the northeast coast of the main island Honshu. In some bays, the wave reached a height of up to forty meters. Entire towns, roads, and railway lines were washed away, hundreds of thousands of houses were destroyed. Some 16,000 people were killed in spite of high protective dykes and an excellent early-warning system. Without these protective installations, the death toll would have been much higher. The tsunami-exposed northeast of Japan is believed to have last been hit by a seismic sea wave of this size in the year 869.
The tsunami led to severe damage at several blocks of the Fukushima 1 nuclear power plant. Some areas within a radius of several kilometers of the plant will remain uninhabitable for a period of many years. Even without considering the consequences of the nuclear accident, the economic losses caused by the quake and the tsunami came to $210bn — the costliest natural catastrophe of all time. The share of insured losses may amount to as much as $40 billion.
The fault line that triggered the quake was actually fairly short, with a length of 450 km. The seabed at the fracture face, however, shifted by 30 to 40 meters. Experts believe that an earthquake of this strength occurs there once every 500 to 1,500 years. The main shock was followed by thousands of aftershocks, the strongest of which, some forty minutes after the main shock, had a magnitude of 7.9.
22 February: Christchurch
Before the tsunami catastrophe in Japan, there had been an earthquake of 6.3 magnitude in Christchurch, New Zealand, on 22 February. The notable aspect of this event was that an earthquake of 7.1 magnitude had hit Christchurch just six months earlier. The seismic waves were amplified due to reflection off an extinct volcano, so that far greater destruction was caused than would have normally been expected with an earthquake of this magnitude. The epicenter was located at a shallow depth and only a few kilometers from the city centre.
The release notes that the losses were enormous. Numerous old buildings collapsed, and many new buildings were damaged despite the very high building standards. Some residential areas will not be rebuilt. Economic losses came to around $16 billion, of which approximately $13 billion was insured.
One day before Christmas, the earth shook again in Christchurch. Over a dozen people were injured following three strong earthquakes. In
