A firestorm occurs when flames from a large number of individual fires merge into a single convective, or circulatory, column. This produces so much heat that all the buildings below are set on fire. Firestorms cover a whole area, trapping the population within them.
During the Second Worlds War enormous destruction was caused by fire in British, German and Japanese cities. In Britain and Germany the thousands of fires started by incendiary bombs usually burned individually, with relatively little spread between buildings. This was because of the materials from which the buildings were constructed, their size and the lay-out of the cities.
However, in Japanese cities mostly made up of low wooden-framed houses the American bombing attacks brought about a number of annihilating firestorms. The most terrible of all was that caused by the atomic bomb dropped on Hiroshima, on August 6, 1945. This storm contributed in great measures to the death toll of 70,000 to 80,000 people. In the second atomic bomb attack on Nagasaki on August 9, 1945, fire damage was again severe.
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