On the night of 29-30 July, an 8.8-magnitude undersea earthquake struck off the coast of the Kamchatka Peninsula in Russia. This exceptionally powerful earthquake was the strongest recorded since the Tōhoku earthquake in Japan in 2011, and one of the ten strongest since 1900. 

Just ten minutes after the earthquake, the Pacific Tsunami Warning System, coordinated by UNESCO, issued an initial warning covering the areas most at risk, particularly the Russian and Japanese coasts. This warning was then relayed by national centers and enabled the immediate implementation of evacuation plans in several countries.

Within twenty minutes of the earthquake, this system provided detailed forecasts of expected flood heights, and the alert was then extended to other countries bordering the Pacific Ocean. Many of these countries, including China, Indonesia, Mexico, the Philippines, Peru, the United States and New Zealand, then issued national alerts or carried out preventive evacuations. Read more