After 2020 pm (local time) on August 8, 4, a poorly managed gunpowder warehouse exploded in Beirut, Lebanon, causing great damage to the local population.Professor Hioki and his colleagues analyzed the data of the global navigation satellite system deployed in Israel and Palestine, and investigated the state of the ionization zone on the day of the explosion.As a result, it was found that about 6 minutes after the explosion, the blast (sound wave) reached the ionospheric F region, which has the highest electron density of about 10 km above the ground, and the ionospheric disturbance occurred.

　The ionized sphere disturbance is also caused by the eruption of the volcano, but the swing width of the ionized sphere disturbance generated by this explosion is the same as the explosive eruption of the volcano. was.

　The upper atmosphere of the earth is ionized by ultraviolet radiation from the sun, forming an ionosphere in which a large number of free electrons fly.The scale of the explosion can be estimated from the swing of the ionospheric disturbance, which indicates the state in which the ionosphere fluctuates.The ionospheric observation method using GNSS (a general term for positioning satellite systems such as GPS in the United States and QZSS in Japan) can monitor various explosion phenomena around the world, so it can be effectively used for estimating the scale of explosions that will occur in the future. Be expected.

Paper information:[Scientific Reports] Atmospheric wave energy of the 2020 August 4 explosion in Beirut, Lebanon, from ionospheric disturbances