The 2011 earthquake off the coast of Japan was one of the biggest ever recorded at 9.0 on the Richter scale, triggering a devastating tsunami that left thousands dead or missing and hundreds of thousands homeless in northeast Japan. Several older nuclear power plants suffered explosions and radioactive leaks as safety systems failed in the aftermath, forcing workers to battle for weeks to bring the situation under control and detect radioactive material. The combined cost of the earthquake and tsunami is estimated at over $300 billion, making it the world's most expensive natural disaster on record and causing global economic repercussions due to Japan's important role in the world economy.