First comprehensive handbookAre all coasts tsunami-ready?

10 March 2026, by Stephanie Janssen

Photo: Jörn Behrens

Part of preparation: tsunami evacuation sign at the beach, here in Arica, Chile.

UNESCO wants all at-risk coasts around the world to be “tsunami-ready” by 2030. Today, on the fifteenth anniversary of the tsunami that struck Japan on March 11, 2011, costing more than 18,000 lives and resulting in a meltdown at Fukushima Nuclear Power Plant, this goal has lost none of its urgency. To achieve it, twelve criteria have to be met. But how can at-risk communities know how to connect early warning systems or how to create an evacuation map? A team led by Prof. Jörn Behrens from the University of Hamburg’s Earth and Society Research Hub (ESRAH) has now released the first comprehensive handbook on tsunami preparedness.

Every year, as many as 30 tsunamis strike populated areas and do extensive damage. But when it comes to tsunami-readiness, not all coasts are created equal. Whereas tsunami catastrophe-prone countries like Japan and Indonesia have become pioneers over the past 15 years, other regions are just getting started. In the worst-case scenario, this could endanger human lives.

“For example, if there’s a quake in the Mediterranean, it takes a maximum of 30 minutes for the wave to reach a coast,” says mathematician Jörn Behrens. “How well prepared the region in question is makes an enormous difference. If the time available is put to optimal use, considerable losses can be avoided.”

A practical guide to minimize risks

And that’s where the new handbook comes in – as a practical guide intended to minimize risks in terms of human life, infrastructure and economic damages. “There’s never been a reference on this topic,” says Behrens. “Here, political decision-makers, administrators and other experts will find the information they need for their individual preparations.”

Freely available online, the book contributes to the implementation of UNESCO criteria. Structured like a cookbook, it includes the fundamental “ingredients” for a risk assessment, together with 25 “recipes” that use examples to combine the building blocks of prevention. The book also introduces readers to essential models, datasets and tools, which decision-makers can adapt to their own local conditions.

How do warnings effectively reach the people?

For example, one chapter helps readers determine whether or not there is a real risk. In the worst-case scenario, how high would the waves be? How many people live in the region? Every region is assessed on the basis of these criteria. In turn, those who are responsible for a given region have to take a closer look. For instance, are buildings near the coast sufficiently robust? Another chapter shows how to assess the vulnerability of houses and critical infrastructure. When there’s been a quake in the ocean, every minute counts. Critical aspects: whether or not there is an established early warning system, how effectively warnings reach the populace – and how they can be sensibly evacuated if necessary.

“We’ve presented key research findings in a user-friendly format for practical use, so that everyone can optimally prepare,” says Behrens. “If readers still have questions, we’re glad to provide individual consulting.”

The book is based on the latest methods from tsunami risk research and draws exclusively on published research findings. Developed as part of the international project AGITHAR (Accelerating Global science In Tsunami HAzard and Risk analysis), which Behrens coordinates, its practical implementation will be further pursued by the Global Tsunami Model Association, which he chairs and which brings together more than 40 experts from all continents.