THE Asian tsunami of 26 December last year sent waves ricocheting around the world. But the pattern of the waves was puzzling. Beaches in Brazil, on the other side of the Earth from the underwater earthquake, were hit by larger waves than the shores of the Cocos Islands just 1700 kilometres away. Now there is an explanation: underwater structures such as mid-ocean ridges and continental shelves funnelled the waves across massive distances.
Vasily Titov of the US National Atmospheric and Oceanic Administration’s laboratory in Seattle and his colleagues collected data from tide gauges around the world and satellite data of…
