Years of steady, quiet pressure on a plate boundary beneath the Pacific ocean resulted in the devastating 9.0-magnitude earthquake.
The Japan Meteorological Agency said a local tsunami of up to one metre (3.3 feet) could impact the Pacific coastline after the quake.
An 8.0-magnitude earthquake strikes off the coast of Alaska prompting a local tsunami warning.
A floating, no-emissions car sounds cool, but how would it actually fare in a large-scale disaster?
If melting ice caps trigger rapid sea level rise, the strain that the edges of continents could experience might set off underwater landslides.
A 'meteotsunami' (or weather-induced tsunami) caused swells on a normally calm estuary on a sunny day in southwest England.