A devastating Tsunami occurred on the Indonesian islands of Java and Sumatra, leading to tragic loss of life and injury. Over 200 people were killed, and hundreds more injured, resulting from an underwater landslide. This unexpected event is thought to be sparked by the eruption of Anak Krakatau volcano.
The History and Threat of Anak Krakatau Volcano
Anak Krakatau, located in the region once occupied by Krakatau that was obliterated in 1883, first appeared in 1927 and has been growing steadily since. In August 1883, Krakatoa experienced one of the most violent volcanic eruptions in recorded history. Tsunamis were triggered by this event, generating monstrous waves of up to 41m that tragically took the lives of over 30,000 people. The calamity didn’t stop there; thousands more deaths resulted from hot ash flows produced by the eruption. The eruptions had the energy equivalent to 200 megatons of TNT – 13,000 times the power of the Hiroshima atomic bomb of 1945. Following this catastrophic eruption, global temperatures fell by more than 1°C, and the volcanic island was almost wiped off the map.
Challenges in Tsunami Warning and Prediction
The full moon’s high seas further agitated the already powerful waves. Tsunami warning buoys, traditionally designed to provide alerts for tsunamis caused by earthquakes at underwater tectonic plate boundaries, failed to warn about the tsunami ignited by volcanic activity. The nearness of the erupting volcano to the coast allowed precious little time for authorities to adequately respond.
| Date | Event | Deaths |
|---|---|---|
| August 1883 | Krakatoa volcanic eruption | 30,000+ |
| September 2018 | Sulawesi earthquake and tsunami | 2,000+ |
| Current event | Anak Krakatau volcanic eruption and tsunami | 200+ |
The Ring of Fire’s Menace: Indonesia’s Tsunami Prone Location
Indonesia’s geographical location makes it particularly vulnerable to tsunamis. It sits on the ‘Ring of Fire’ – this is a major area in the basin of the Pacific Ocean where a large number of earthquakes and volcanic eruptions occur. The peril was starkly made evident in September 2018 when an intense earthquake just off the central Indonesian island of Sulawesi triggered a tsunami, resulting in a death toll exceeding 2,000.
About Tsunami:
Tsunami, a term originating from Japan, means a harbor wave. Often referred to as killer waves, a tsunami is not just a single wave but a series of ocean waves or a ‘wave train’. Causes of these deadly waves include underwater earthquakes, volcanic eruptions, landslides, rapid atmospheric pressure changes, or impact from a meteorite. Despite volcanic activities being less common triggers, most tsunamis (around 80%) occur within the Pacific Ocean’s “Ring of Fire,” due to its geological activity. Tsunamis can travel across the sea at speeds up to 500 miles (805 kilometers) per hour, comparable to a jet airplane, crossing the entire expanse of the Pacific Ocean in less than a day. Due to their long wavelengths, they lose minimal energy while traveling. The UN General Assembly has designated November 5 as World Tsunami Awareness Day since December 2015.
