Posted on behalf of Chloe McIvor.

As murky torrents swirled around Sendai airport in Japan following the earthquake and tsunami in March, geographer Mark Maslin and his team were horrified to see their predictions coming true.

Maslin’s team at University College London Environment Institute (UCLEI) had been working on the first global assessment of tsunami risk to airports in January 2010. Sendai was one of 10 international airports studied but their research couldn’t pre-empt this most recent disaster. It is hoped that the project, commissioned by insurance broker JLT Re, will help the aviation industry accurately assess the financial risk posed by tsunamis as well as aiding the reassessment of defences.

When airports such as Sendai go down during a natural disaster it can severely damage international aid imports and, in the long term, can have crippling effects on the economy, not only in terms of insurable damage to aircraft on the tarmac, but also to international trade. Sendai was completely out of action for one month and Japan’s Transport Ministry announced only last Friday that they plan to resume international flights on 25 July.

The UCLEI project was a collaborative effort between the (re)insurance industry and the scientific community to identify tsunami risk, which was previously labelled a “known-unknown” by insurers. This new knowledge is to be used within the aviation industry for the benefit of JLT Re clients, but the methodology will have wider applications.

The researchers say their methods can be applied to other forms of coastal infrastructure such as nuclear power plants and ports. Matt Owen, a PhD student at UCLEI who conducted the research, explained that the project began with mapping based on a catalogue of tsunamis from the US National Oceanic and Atmospheric Association. The project looked at geographical factors specific to each of the 10 international airports studied: Hong Kong; Incheon, in Korea; Changi, in Singapore; PuDong, in China; Kasnsai, Chubu, Haneda, and Sendai in Japan; Honolulu in Hawaii, and JFK in New York. The recently submerged Sendai is classed as ‘high risk’ according to the study but the project identified Chubu, Haneda and Honolulu as even more vulnerable (See this chart).

The UCLEI method assesses the factors affecting the likelihood and resultant impact of tsunamis. Likelihood was discerned from the interval between tsunami events in that area: airports at very high risk had a recurrence interval of less than 25 years. The typical magnitude of these tsunamis was catagorised based on their maximum on-shore height. Other considered factors included the position of the airport in relation to the coast, the location of parked aircraft, runways and terminal buildings, local topography, and the degree of inundation required to cause damage. “Current engineering models underestimate peak wave height and thus damage caused by tsnamis,” says Maslin, as was the case with the most recent disaster in Japan.

This collaboration between academia and the insurance industry provides a scientific framework on which to base the assessment of other potential ‘metrocatastophes,’ and should be used to ensure that other high risk airports are not victims of underestimation.

For full coverage of the Fukushima disaster, go to Nature’s news special.

Image courtesy of stroud4341 via Flickr under Creative Commons.