The Indian Ocean tsunami has prompted a re-evaluation of existing warning systems for natural disasters and the way warnings are issued. One concern is that false alerts could increase the cost of running a warning system.

In this letter to Nature, risk analyst Gordon Woo and earth scientist Willy Aspinall, say risk specialists could play an important role in the design of tsunami warning systems, capable of issuing different levels of warning, similar to the system used for gale warnings. This would mean low-level alerts could be issued hours in advance, allowing the sea and beaches to be evacuated.

The authors say that in densely populated areas such as the countries surrounding the Indian Ocean, the occasional low-level false alert would be acceptable in view of the considerable loss of life that would occur if a warning system was not in place. 

Link to full article in Nature 

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