Which of the world’s airports is at greatest risk of getting hit by a tsunami? You might guess it’s in Japan, but it isn’t Sendai, which was struck by the tsunami caused by the 11 March megaquake. Instead, one of Tokyo’s international airports is in line for the most frequent and severe catastrophes.

Matt Owen of University College London used historical data from the US National Oceanographic and Atmospheric Administration on the number and size of tsunamis around the world, and combined this with the frequencies of earthquakes and other events that cause tsunamis. That allowed him to compare the overall risks to different coastal regions. He found that Pacific coasts face the highest risk.

Owen then focused on 10 coastal regions with an airport and ranked them on a scale from 1 to 5 on the severity of the tsunamis they had experienced since local records began, and the frequency with which they occurred. Tokyo International Airport, also known as Haneda airport, scored 5 on both.

By comparison Sendai airport, which was closed for a month after the March tsunami flooded it, scored 4 on both. Central Japan International Airport, near Nagoya, ranked 4 for frequency but 5 for severity, while Honolulu airport in Hawaii ranked 5 for frequency but 4 for severity.


All these at-risk airports have defences, but it is unclear if they are sufficient. “Japan has the best tsunami defences in the world,” Owen says, yet they were overwhelmed by an unexpectedly large wave. He says coastal airports around the world should reassess their tsunami risks.

It’s crucial to protect airports, because as well as supporting the local economy they are vital for bringing aid into disaster areas, says Mark Maslin, a colleague of Owen at University College London.

The research was carried out for the reinsurance brokers JLT Re and presented in London this morning.