Sooty smoke from fires raging in the wake of a global atomic war could lead to an even deeper, darker "nuclear winter" gripping the planet, a British researcher warned Wednesday.
The nuclear winter theory is advanced by scientists who believe an extended period of global cooling caused by smoke and dust blocking out the sun's rays would follow a worldwide atomic exchange.Scientists speculate such a fiasco - which could last for weeks, months or years - would plunge Earth's surface into near or total darkness, cause temperatures to fall and disrupt harvests and food production.
In an article appearing in the British journal Nature, Jenny Nelson of the University of Bristol in England wrote, "The sooty fraction of the smoke produced by fires in the wake of a nuclear exchange is a critical factor in determining climatic effects."
Nelson suggested sooty smoke clouds consist of chains of particles that block out even more sun light than previously thought.
"Sooty smoke is formed during the non-flaming combustion of oils, plastics and construction material," Nelson wrote. "It absorbs sunlight strongly."
Using a computer model, the British physics researcher determined, "The short-term effect of soot . . . is to make the nuclear winter colder by several (up to 5 Celsius) degrees.
"Its long-term effect could be a doubling or trebling in the opacity of the residual smoke layer believed to stabilize in the upper atmosphere," she said. "Both effects are very significant in biological and climactic terms."
In 1982, scientists Paul Crutzen of Berlin and John Birks called attention to the possibility of nuclear war having a profound impact on the atmosphere in a paper published in the International Environmental Journal of the Royal Swedish Academcy of Sciences.
Based on their work, astronomer Carl Sagan and atmospheric scientists constructed a computer model of Earth's atmosphere and calculated the consequences of more than a dozen scenarios of nuclear war.