Читать книгу Witness to Disaster: Tsunamis - National Kids Geographic - Страница 7

On the afternoon of March 11, 2011, a humungous earthquake struck northeastern Japan. It measured 9.0 on the magnitude scale. Only three larger quakes have shaken our planet in the past century.

The earthquake occurred when two large chunks of our planet’s crust fractured beneath the sea off the coast of Japan. The rupture thrust part of the ocean floor under the island nation, dropping its coastline two feet while lifting the land beneath the sea. This double motion caused the Pacific Ocean waters to slosh like soup in a bowl, creating massive waves called tsunami.

Because Japan is one of the most earthquake-prone places on our planet, the Japanese people are well prepared for both earthquakes and tsunamis. Homes and large buildings in Japan are built to withstand large quakes. A state-of-the-art tsunami warning system is in place, and Japanese children and adults undergo regular drills to make sure they know what to do during such disasters.

But nothing could prepare the residents of northeastern Japan for the gigantic waves that hit their coast an hour and a half later. Walls of water as tall as 30 feet (9 meters)—the height of a three-story building—slammed into coastal Japanese cities at the speed of a jet airplane. The water flooded areas more than five miles inland, killing tens of thousands of residents.

The power of the water was so intense that tsunami warnings were issued for coastal Hawaii, 3,850 miles (6,200 kilometers) from Japan. Waves taller than three feet (one meter) high hit the Hawaiian coast seven and a half hours after the quake struck Japan.

Crescent City, California, lies 4,763 miles (7,700 kilometers) from the coast of Japan. Nevertheless, ten hours after the earthquake, an eight-foot (two-meter) tsunami wave slammed into that harbor city, destroying a pier and reducing dozens of boats to rubble.

Sophisticated tsunami warning systems throughout the Pacific Ocean prevented even greater loss of life. You will learn more about tsunamis and the systems that warn people about them in the following chapters.