Indian Ocean tsunami of 2004

Indian Ocean tsunami of 2004, tsunami that hit the coasts of several countries of South and Southeast Asia in December 2004. The tsunami and its aftermath were responsible for immense destruction and loss on the rim of the Indian Ocean.

Earthquake and tsunami

On December 26, 2004, at 7:59 am local time, an undersea earthquake with a magnitude of 9.1 struck off the coast of the Indonesian island of Sumatra. Over the next seven hours, a tsunami—a series of immense ocean waves—triggered by the quake reached out across the Indian Ocean, devastating coastal areas as far away as East Africa. Some locations reported that the waves had reached a height of 30 feet (9 meters) or more when they hit the shoreline.

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The tsunami caused one of the largest natural disasters in recorded history, killing an estimated 228,000 people in many low-lying coastal areas across 15 countries, with Indonesia, Sri Lanka, India, Maldives, and Thailand sustaining massive damage. Indonesian officials estimated that the death toll there alone ultimately exceeded 200,000, particularly in northern Sumatra’s Aceh province. Tens of thousands were reported dead or missing in Sri Lanka and India, a large number of them from the Indian Andaman and Nicobar Islands territory. The low-lying island country of Maldives reported more than a hundred casualties and immense economic damage. Several thousand non-Asian tourists vacationing in the region also were reported dead or missing.

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Disasters of Historic Proportion

The lack of food, clean water, and medical treatment—combined with the enormous task faced by relief workers trying to get supplies into some remote areas where roads had been destroyed or where civil war raged—extended the list of casualties. Long-term environmental damage was severe as well, with villages, tourist resorts, farmland, and fishing grounds demolished or inundated with debris, bodies, and plant-killing salt water. In Indonesia alone, such widespread destruction affected the lives and livelihoods of more than 1 million people.

International response

Many countries across the world, the United Nations, and humanitarian organizations came to the aid of the affected regions in the days and months following the tsunami. In the aftermath of the tsunami, commemorative monuments were established in many countries. The Ban Nam Khem Tsunami Memorial Park in Phang Nga, Thailand; the Tsunami Honganji Viharaya in Peraliya, Sri Lanka; the Aceh Tsunami Museum in Banda Aceh, Indonesia; the tsunami memorials in Kanniyakumari, Nagapattinam, and the Andaman and Nicobar Islands, India; and the Indian Ocean Tsunami Memorial in Kings Park, Australia, serve as reminders of the loss brought about by the tsunami.

Prior to the 2004 tsunami, the Indian Ocean had no appreciable tsunami warning system. The devastation brought on by the 2004 event prompted the government of India to develop its own tsunami early warning system, which became fully operational in 2007. In addition, the tsunami motivated countries and organizations to improve existing tsunami warning and disaster management systems worldwide. The Indian Ocean Tsunami Warning and Mitigation System (IOTWMS), established in 2005 under the Intergovernmental Oceanographic Commission (IOC) of UNESCO, is an international initiative that aims to continually improve tsunami preparedness among all 28 member states through comprehensive risk assessment, early warning capabilities, and community awareness programs. The IOC’s Tsunami Ready Recognition Programme, launched internationally in 2008, promotes community preparedness through education and drills, enhancing local readiness and ensuring that at-risk communities are informed and resilient during tsunami events.