Nine examples of tsunami readiness – turning warnings into life-saving action
A tsunami can reach the coast within minutes of an earthquake or other sudden disturbance, sometimes before any official alert. What people already know, and what they do in those first minutes, often decides who survives.
Tsunami early warning has changed a great deal since 2004. Regional networks now detect threats and issue alerts in every major ocean basin, and in recent years the UN Secretary-General’s Early Warnings for All initiative has widened the reach of multi-hazard warning systems. But a warning still has to reach someone who understands it and acts on it, whether that is a driver with a siren or a child with an evacuation map.
That is the idea behind this year’s World Tsunami Awareness Day theme, “Be Tsunami Ready: Resilience Begins with You”.
The nine stories below span more than 170 years. In each, something put in place well before the wave – a warning system, a school drill, a story handed down – helped people reach safety, or is preparing the next generation to do so.
1. A burning rice harvest saved a Japanese village in 1854 – and gave World Tsunami Awareness Day its date
During the 1854 Ansei-Nankai tsunami – which claimed an estimated 3,000 lives along the coast of western Japan – Hamaguchi Goryo, a village leader who recognised the warning signs, set fire to his harvested rice sheaves on a hill. Villagers rushed uphill to fight the blaze and found themselves above the wave as it destroyed the village below. The story, Inamura no Hi or “the fire of rice sheaves” is widely used around the world to teach tsunami safety, and 5 November, the date of that tsunami, is now marked each year as World Tsunami Awareness Day.
2. One driver with a siren cleared Tonga’s coastline in time
When the Hunga Tonga-Hunga Ha’apai volcano erupted on 15 January 2022 and sent a tsunami towards Tonga, a driver with the Emergency Management Office, Li’oa, got into his vehicle, switched on the siren and told people to move away from the coast. Four people died in the Tonga tsunami, which saw waves reaching 20 metres. Fast warnings and a population that knew what to do kept the toll that low. Li’oa’s story, published as a UNDP Tsunami Story Book for children, shows that the last mile of an early warning system is often covered by a person willing to carry the message.
3. The schoolchildren of Kamaishi knew where to run
When the Great East Japan tsunami struck in March 2011, 99.8 per cent of schoolchildren in Kamaishi, Iwate Prefecture, survived. From 2006, Professor Toshitaka Katada had worked with local schools on a few simple evacuation principles, and every child drew a personal evacuation map showing their home, their route to school and the nearest evacuation area. After five years of practice, the children knew what to do and acted on their own when the time came.
4. The Pacific’s tsunami warning system held when Kamchatka shook in 2025
When a magnitude 8.8 earthquake struck off Russia’s Kamchatka Peninsula in July 2025, tsunami alerts went out across the Pacific within minutes. More than 1.9 million people evacuated in Japan, with around 2,700 more in Russia’s Sakhalin region. The Pacific Tsunami Warning and Mitigation System, in place since 1965, detected the threat. Coastal sirens, mass text alerts and years of evacuation drills did the rest.
5. Simeulue’s islanders ran for high ground the moment the shaking stopped
On 26 December 2004, people on Simeulue, the inhabited island closest to the earthquake’s epicentre, headed uphill at once. Only seven of the island’s tens of thousands of residents died. They were acting on smong, a word that islanders have passed down in lullabies and stories since a tsunami hit Simeulue in 1907. It names the whole sequence: the earthquake, the sea drawing back and the giant wave that follows.
6. A Moken sea nomad raised the alarm when the cicadas fell silent
That same boxing-day morning, a member of the Moken sea nomad community in the Andaman Sea, South East Asia, noticed that the cicadas had become quiet and warned everyone to move. The Moken community reached safety and alerted tourists on nearby beaches. Their legend of the laboon, “the wave that eats people”, says the sea draws back and the cicadas fall silent before it comes. Knowledge like this is rarely written down, which makes it easy to lose.
7. Samoan schoolchildren rehearse the evacuation their communities needed
In October 2017, 1,400 students and teachers at six schools hit by the 2009 tsunami took part in a simultaneous evacuation drill, the first on that scale in Samoa. In 2009 the wave reached the coast within minutes of an offshore earthquake, and many people had too little time to escape. Samoa’s Disaster Management Office says the drills will continue, and its Multi-hazard Early Warnings for All Roadmap now sets out a ten-year plan to 2036.
8. Japan’s survivor-storytellers keep the lessons of 2011 in circulation
Across north-eastern Japan, survivors known as kataribe share what happened in 2011 with visitors and younger generations at more than 300 memory sites linked through the 3.11 Densho Road network. In Yamamoto, Miyagi Prefecture, the “Life is a Miracle” initiative uses one survivor’s motorcycle, which the ocean carried all the way to Haida Gwaii in Canada, to start conversations about loss and preparedness. Since 2024, Japan has formally certified storyteller programmes, memorial sites and similar efforts as national disaster prevention assets.
9. A ten-year-old remembered a geography lesson and cleared a beach
On 26 December 2004, ten-year-old Tilly Smith was on holiday with her family at Mai Khao Beach in Phuket, Thailand, when she noticed the sea surging and frothing, and recognised these warning signs from a geography lesson two weeks earlier. She told her parents and alerted hotel staff, who cleared the beach before the wave arrived. Around 100 people owe their lives to that lesson.
Each of these quick reactions began long before the sea stirred – in a geography lesson, a grandmother’s lullaby, a siren within reach, a warning system someone chose to fund. Readiness is built in the years and decades between extreme events, by people who decide the next potential disaster is worth preparing for.