On March 11, 2011, a magnitude 9 earthquake 80 miles off the northeast coast of Japan triggered a series of tsunamis that struck nearby shorelines with only a few minutes’ warning. The disaster left dozens of villages along nearly 200 miles of coast heavily damaged or completely destroyed.
The waves, some of which measured more than 40 feet, also struck the Fukushima Daiichi nuclear power plant 150 miles north of Tokyo, disabling the plant’s emergency systems and, over the following weeks, resulted in the largest accidental release of radiation to the environment in history. Because of the plant’s location, much of this contamination washed into the Pacific. Additional, airborne radioactive material likely fell onto the sea surface, where it too mixed into the water.