Blast from N.Korea's New Nuke 'Could Obliterate Seoul'
North Korea conducted a test of a nuclear weapon on Sunday believed to have been in the 50 to 100-kiloton range, way more than the 15-kiloton bomb dropped on Hiroshima.
The North is also thought to be close to miniaturizing a nuclear weapon so it can be mounted on a ballistic missile, though it is unclear whether the weapon was really a hydrogen bomb, as the North has claimed.
The damage from a blast of that magnitude could raze all of Seoul and parts of surrounding Gyeonggi Province. South Korean military experts estimate the strength of the latest North Korean nuclear test at around 50 kilotons, which is smaller than estimates by the U.S., China and Japan.
A military expert said, "50-kiloton marks the borderline between a boosted fission bomb and hydrogen bomb," which would result in leveling an area 1.7 times greater than the devastation in Hiroshima.
The U.S. Defense Department conducted a simulated test in 1998 to determine the extent of damage Seoul would suffer if a 15-kiloton nuclear weapon blew up over its Yongsan garrison in the center of the city.
The test showed structures within a 150 m radius disintegrating and people within a 1.5 km radius suffering third-degree burns. An estimated 620,000 people would die. The Hiroshima blast killed around 135,000 people.
But considering the higher population density of Seoul, the fatalities would be even higher, and experts estimate around 2 million fatalities if a 50-kiloton nuclear weapon blows up over Seoul. If it explodes 100 km over Seoul, the electromagnetic pulse would immobilize all electronic devices.
But the South Korean government has always underestimated the intensity of North Korea's nuclear blasts. It said it detected an earthquake of 5.7 on the Richter scale after Sunday's test, while the U.S. and China measured a 6.3 tremor, which is equivalent to a 200 to 1,000-kiloton nuclear weapon.
A 100-kiloton nuclear weapon exploding over Seoul would result in damage to an area 2.5 times greater than Hiroshima, which means most of the capital being reduced to cinders. Structures within a 370 m radius of such a blast would evaporate, while those within a 2.5 km radius would either burn or melt. No living being would survive such a catastrophe.
People within a 3.75 km radius of such a blast would suffer third-degree burns and buildings within an 11.25 km radius would suffer massive damage.