Environmental devastation that some scientists contend would result from a nuclear war.
The basic cause, as hypothesized, would be huge fireballs created by exploding nuclear warheads, which would ignite great fires (firestorms). Smoke, soot, and dust would be lifted to high altitudes and driven by winds to form a uniform belt encircling the Northern Hemisphere. The clouds could block out all but a fraction of the Sun's light, and surface temperatures would plunge for as much as several weeks. The semidarkness, killing frosts, and subfreezing temperatures, combined with high doses of radiation , would interrupt plant photosynthesis and could thus destroy much of the Earth's vegetation and animal life. Other scientists dispute the results of the original calculations, and, though such a nuclear war would undoubtedly be devastating, the degree of damage to life on the Earth remains controversial.