Why did we lose the 59 climbers in 2014 Ontake Volcano Eruption?

Abstract:

The first historical eruption at Ontake volcano, central Japan was in 1979, and it was a phreatic eruption. Until then, most Japanese volcanologists understood that Ontake is a dormant or an extinct volcano. Re-examination of active volcanoes was done after the eruption.
After the first historical eruption in 1979, two small eruptions are repeated in 1991 and 2007. Through the three eruptions, nobody has got injured. The last eruption on September 27, 2014, we lost 65 people included missing. Because it was fine weekend and there were many climbers on the summit. The eruption was almost at lunchtime.
Clearly, casualties by tsunamis are inhabitants along the coastlines, and casualties by eruption are visitors not inhabitants around the volcano. Basically, visitors have small information of Ontake volcano. After the accident, one mountain guide tells us that we never have long broken such as lunch around the summit, because an active creator is close, and they are afraid of the volcano gas accidents. All casualties by eruption were lost their lives in the area of 1.0 km distance from the 2014 creators.
In 2004 Sumatra Earthquake Tsunami, we could not recognize the tsunami inspiration between the habitants in Banda Aceh, Sumatra. They have no idea of tsunami, and they called “Rising Sea” never“Tsunami”. As the result, they lost many habitants close to the coast.
In 2011 Tohoku Earthquake Tsunami, when habitants felt strong shaking close to coast, they understood the tsunami coming. 0ver 50 % habitants decide to evacuate from the coast. However, 20-30 % habitants believe in themselves no tsunami attacking for them. As a result we lost many habitants.
Additionally, the tsunami height was higher than broadcasting one by JMA. According to the results of the questionnaire survey in climbers or bereaved families of the eruption day on Ontake volcano (Shinano Mainich Newspaper, 2015), 39 % of them were climbing no understand of “Ontake active volcano”. Moreover, only 10-20 % of them was understanding some seismic activities in September. I met some bereaved family, and I understand the climbers are almost beginners.
On the one hand, JMA, government and local governments never understand the experience of climbers of Ontake volcano. It was the main cause of the 2014 Ontake eruption accident.