Here's why small tsunami waves still trigger mass evacuations worldwide

A powerful 8.8 earthquake struck off Russia's Kamchatka coast, triggering tsunami warnings and evacuation orders across multiple Pacific nations, including Japan, Hawaii, and Chile

One of the largest earthquakes ever recorded — 8.8 magnitude tremor — struck off the coast of Russia’s Kamchatka Peninsula on Wednesday, triggering tsunami warnings and evacuations across the Pacific. Although the quake’s power was immense, the resulting tsunami waves are projected to be relatively moderate, raising questions and concerns around evacuation protocols and public safety, The Conversation reported.

 

What is happening

The epicentre of the earthquake was the sea near Kamchatka, a remote peninsula facing the Pacific Ocean. Russia reported waves up to 4 metres high. Other regions, including Japan, China, Hawaii, and even South American countries like Ecuador and Chile, are projected to see waves ranging from 30 cm to 3 metres.

 

 

What are scientists saying?

US earthquake scientists Judith Hubbard and Kyle Bradley advised not to second-guess a tsunami warning, but to evacuate to higher ground and wait for the all-clear. “The actual wave height at the shore depends on the specific bathymetry [underwater topography] of the ocean floor and shape of the coastline. Furthermore, how waves impact the coast depends on the topography on land,” said Hubbard and Bradley, as quoted by The Conversation.   

 

The context

Tsunami waves, even when small, can carry dangerous force and escalate rapidly. Experts said it is safer to evacuate early than risk delays. “Too early is far better than too late,” one expert said, as quoted by The Conversation. Uncertainty is built into early warnings, which often rely on limited quake data before tsunami measurements become available. 

Behavioural scientists have found that evacuation compliance increases when people believe the threat is real, trust authorities, and see others around them taking action. However, when people act outside official guidance, known as “shadow evacuation”, they can clog roads, overload shelters, and create unnecessary risk.

 

The bigger picture

Wealthy nations like Japan, which frequently face tsunamis, have invested in early warning systems, drills, vertical shelters, and coastal sirens. In contrast, developing nations often lack such infrastructure, leading to higher casualties during disasters.

Following a costly false alarm in Hawaii in 1986, the US developed the DART (Deep-ocean Assessment and Reporting of Tsunamis) system, which uses deep-sea buoys to monitor real-time ocean pressure. This has helped reduce false alarms and improve public trust in alerts.     

  

Lessons from history

The 2004 Indian Ocean tsunami, triggered by a 9.1 magnitude quake, killed over 227,000 people in Indonesia, India, Sri Lanka, and Thailand — areas with little warning infrastructure. In contrast, Japan’s 2011 tsunami, despite being caused by an even stronger quake, saw fewer deaths thanks to stronger preparedness and faster evacuations. 

In 2018, more than 4,000 people died in Sulawesi, Indonesia, after a 7.6 magnitude quake caused a tsunami. Public disbelief and poor communication hampered timely evacuation.

 

What to do

Tsunamis are rare but catastrophic. Authorities stress that when an evacuation order is issued, it must be taken seriously. Early, orderly action saves lives, far more than waiting until roads are flooded and panic has set in.