When every minute counts: China's race to strengthen tsunami warnings

Every year on November 5, the United Nations observes World Tsunami Awareness Day to call for stronger early-warning systems, preparedness and coastal resilience.

Tsunamis are rare but devastating; they can claim hundreds of thousands of lives. As sea levels rise and more people live along coasts, building reliable warning systems has become a global priority.

On December 26, 2004, a massive earthquake off northern Sumatra triggered tsunami waves that struck many shores around the Indian Ocean, killing over 200,000 people. The disaster revealed a deadly gap: the region then lacked a coordinated warning network.

Over the past century, 58 major tsunamis have taken more than 260,000 lives, making preparedness an urgent international task.

In 2011, Japan's Tohoku region was hit by a magnitude-9 earthquake and tsunami that breached seawalls and caused the Fukushima nuclear accident. Japan's experience shows that resilience depends not only on physical barriers but also on land-use planning, evacuation drills and public awareness.

Indonesia's 2018 disasters – one earthquake-induced, another caused by a volcanic collapse – proved that tsunami sources vary and some strike with almost no warning.

Such events underscore why nations must act quickly to detect, alert and respond before waves reach the shore.

Learning from these lessons, many coastal countries are investing in faster alerts and cross-border cooperation. One key example comes from China's effort to build a regional multi-hazard warning network in the South China Sea.

The risk of large tsunamis in the South China Sea primarily comes from the Manila Trench that lies in the Philippines. It is often associated with frequent earthquakes and volcanic activities.

The South China Sea Tsunami Advisory Center (Hainan) started operation in South China's Hainan Province on June 8, 2025, aiming to provide marine disaster early warning services for regional countries.

Established by the National Marine Environmental Forecasting Center and the Hainan provincial oceanic administration, the center seeks to develop a comprehensive multi-hazard early warning system for tsunamis, marine heatwaves, harmful algal blooms and other hazards. It also aims to serve as a platform for international cooperation in marine forecasting and warning.

On the same day, a deep-sea test site was also launched in Sanya, Hainan, to support fundamental deep-sea scientific research, technological innovation and the development of related industries.

When seabed earthquakes trigger tsunamis, seismic stations can detect shocks within minutes, but waves may take hours to reach coasts. China's technologies rank among the world's most advanced: its global quantitative warning system can issue tsunami alerts within six to 15 minutes after an earthquake, said Gao Yi, associate research fellow at the Tsunami Warning Center of the Ministry of Natural Resources.

The UN-led Tsunami Ready program urges nations to turn awareness into action. Early warning and early response save lives, but technology must connect with communities – if alerts don't reach people who know how to act, they mean little.

World Tsunami Awareness Day is a call for preparedness, not remembrance. Investment, training and shared responsibility can ensure no coastline is caught off guard. As UN Secretary-General Antonio Guterres said, "On this 10th World Tsunami Awareness Day, let us invest in preparedness – for every coastline and every community, everywhere."

For more: First discovery of ancient tsunami site on China's coastline

(With input from Xinhua)

(Cover via VCG, designed by CGTN's Liu Shaozhen)