A sleeping giant, Mount Baekdu’s last major eruption was bigger than the Mt Tambora eruption of 1815, which triggered “The Year Without a Summer.” (Locals called it called it “Eighteen Hundred and Froze to Death.”)
That eruption, which took place about 969 ±20 AD, deposited tephra as far away as northern Japan, a distance of 1200 km (745 miles), and was one of the largest eruptions in the world in the past 10,000 years.
Mount Baegdu is on the verge of erupting, says geologist Yoon Seong-hyo from Pusan National University, who has been monitoring the 2,744 meter-high volcano with an electronic distance measurement device (EDM) for years.
Lake Tianchi (Sky Lake) occupies the summit caldera of Mount Baekdu. Image credit: Xiang Liu, 1983 (Changchun University).
“The mountain’s height has risen about 10 cm between 2002 and 2005,” says Professor Yoon. “It then began to sink in 2009. The shift changed only recently, which is significant.” (KoreaTimes)
However, the height of caldera has risen 1 cm since July 2014.
The temperature from the caldera’s geyser had been around 70 °C, but recently rose to 83 °C. The helium concentration rate had also recently jumped from 6.5 times that of the normal atmosphere from 2002 – 2005 to seven times.
“All these signs indicate the magma inside the mountain is moving upward,” Yoon said.
The massive Changbaishan stratovolcano, also known as Baitoushan, Baegdu or P’aektu-san, is considered the most dangerous volcano in China due to its history of large explosive eruptions, says John Search on his volcanolive.com website.
Its 969 AD eruption was about 50 times stronger than that of Mt. Vesuvius in 79 A.D., which buried and destroyed the Italian city Pompeii.
A growing number of scholars have linked the collapse of Korea’s ancient kingdom, Balhae, with the 10th-century eruption.
The volcano’s most recent eruption took place in 1903. It has been quiet since that time.
http://www.volcanolive.com/baitoushan.html
See also my 2012 post:
http://iceagenow.info/2012/05/growing-fears-huge-north-korean-volcano-erupt/
Thanks to Guy Wilson for this info