World War II Bombings Weakened Earth's Upper Atmosphere at Edge of Space
The Earth's electrified upper atmosphere (the ionosphere) experiences a lot of natural variation, changing with the days and from season to season. The ionosphere can also be affected by certain big events, including solar flares, volcanic eruptions, lightning—and the massive bombs dropped on Germany during World War II. Those bombings produced shockwaves strong enough to weaken the ionosphere right near the edge of space.
That's the conclusion of a new study by University of Reading researchers, just published in the journal Annales Geophysicae. More than a historic curiosity, the finding matters because ionospheric disturbances can disrupt key communications technology, including GPS systems, radio telescopes, and radio communications.
The air raids conducted by both the Germans and Allied forces in the 1940s were designed to take out critical industrial and political infrastructure—and if civilians happened to be in the line of fire, so be it. (The Allied bombing of Hamburg in 1943 reportedly left 45,000 dead.) Intensifying the fear of dying among residents was as key to the strategy as the physical destruction wrought by the massive bombs dropped. The largest bombs, weighing as much as 10 tons, were powerful enough to blow the roofs off buildings, sending intense shockwaves not just through the streets but into the skies above.
"Residents would routinely recall being thrown through the air by the pressure waves of air mines exploding."
“Aircrew involved in the raids reported having their aircraft damaged by the bomb shockwaves, despite being above the recommended height," says co-author and historian Patrick Major. "Residents under the bombs would routinely recall being thrown through the air by the pressure waves of air mines exploding, and window casements and doors would be blown off their hinges. There were even rumours that wrapping wet towels around the face might save those in shelters from having their lungs collapsed by blast waves, which would leave victims otherwise externally untouched.”