Japan's cities vulnerable to storms

The shocking photos and reports of superstorm Sandy, which struck America’s east coast last week, were an important reminder that Japan’s coastal cities could suffer a similar fate. According to a report from the Organization for Economic Cooperation and Development, many Asian mega-cities remain highly vulnerable to such storms. In that survey, New York City ranked 17th for risks from storms, while Tokyo ranked 19th overall.

Japan’s largest cities have dense populations and high concentrations of assets in coastal areas. In terms of assets exposed, Osaka-Kobe, Tokyo (including Chiba and Yokohama) and Nagoya are among the top 10 vulnerable cities in the world. That ranking is partly due to the relatively higher building costs and land values compared with cities in developing countries; however, damage from storms would be higher as well.

The exposure of the population in Japanese port cities to potential wind damage is extremely high. Tokyo ranks highest in the world for exposure to potential wind damage, with Osaka-Kobe in sixth place.

These risks are not likely to decrease. Climate specialists note that changing conditions make it more likely that extreme weather will continue. Sea levels are rising and the rise in average temperature of the oceans increases the severity of storms.

Warmer water and warmer air combine to fuel hurricanes and form conditions that make storms more severe. The season for hurricanes is starting earlier and lasting longer.

Japanese cities have a reasonably high degree of preparation compared with other Asian cities. But the Tohoku disasters of March 11, 2011, clearly demonstrated that better preparation can save more lives.

Even though superstorms like last week’s Sandy are considered “once in a hundred years” events, Japan’s central government and local governments in coastal areas still need to increase preparedness in the short run and urban planning in the long run.

Japanese buildings, particularly older ones near coasts, need inspection and infrastructure that citizens depend on during typhoons needs regular upgrading. New buildings constructed in vulnerable coastal areas should be made to withstand the most fierce typhoons. Post-storm management is also essential since the difference in damage between short-term flooding and long-term flooding, for example, is immense.

Although it is impossible to predict when, or if, a superstorm like Sandy will hit Japan, investment in protective measures should still be undertaken to ensure the safety of Japan’s population.