Today marks the 70th anniversary of the beginning of the 1947 Hekla eruption, the largest volcanic eruption in Iceland in the 20th century, RÚV reports. On March 29 that year, at 6:41 am, Hekla erupted after being dormant for 102 years. A journalist from Morgunblaðið described it this way: “The fire pillars at the top of the mountain stretch 800 m into the air. They hurl up glowing rocks, enormous in size. The large rocks shoot up with magical power before dropping back down into the ocean of fire.”
The eruption lasted for more than a year, emitting about 0.8 km3 of lava which covered 40 km2 of land. The first day, the eruption created about 30 million m3 of ash.
Sharp earthquakes hit at first, and then the eruption began with a bang; a 4-km (2.5 mi) long fissure opened up, and the plume of ash quickly reached a 30-km (18.6 mi) height. Lava streamed down the mountain, and meltwater caused a large flood in the river Ytri-Rangá. A huge ash fall caused substantial damage south of the mountain.
Geophysicist Páll Einarsson told RÚV the eruption attracted enormous attention, not least since it was the first large eruption in Iceland since Katla erupted in 1918. People traveled in large groups from Reykjavík to observe the eruption from Þjórsárdalur valley, South Iceland, a 20-km distance from the volcano.
The 1947 eruption was the first volcanic eruption in Iceland to be photographed and filmed. Journalists and reporters from all the country’s major news media took a flight to the vicinity of Hekla at noon, the day the eruption began. A reporter from the state-run radio station described what he saw through the plane’s radio, which was then recorded and broadcast almost live.