This makes a small to medium sized nuclear conflict more dangerous, but also makes such a conflict less likely as even a successful first strike would result in disaster for the aggressor:
“Although the ongoing Nuclear Posture Review is supposed to include all aspects of the strategy and doctrine that govern the use of U.S. nuclear weapons, it once again will not consider one crucial question: What would be the long-term consequences to Earth’s environment if the U.S. nuclear arsenal were detonated during a conflict?
This isn’t a question to be avoided. Recent scientific studies PDF have found that a war fought with the deployed U.S. and Russian nuclear arsenals would leave Earth virtually uninhabitable. In fact, NASA computer models have shown that even a “successful” first strike by Washington or Moscow would inflict catastrophic environmental damage that would make agriculture impossible and cause mass starvation. Similarly, in the JanuaryScientific American, Alan Robock and Brian Toon, the foremost experts on the climatic impact of nuclear war, warn that the environmental consequences of a “regional” nuclear war would cause a global famine that could kill one billion people.
Their article, “Local Nuclear War: Global Suffering,” PDF predicts that the detonation of 100 15-kiloton nuclear weapons in Indian and Pakistani megacities would create urban firestorms that would loft 5 million tons of thick, black smoke above cloud level. (This smoke would engulf the entire planet within 10 days.) Because the smoke couldn’t be rained out, it would remain in the stratosphere for at least a decade and have profoundly disruptive effects. Specifically, the smoke layer would block sunlight, heat the upper atmosphere, and cause massive destruction of protective stratospheric ozone. A 2008 study PDF calculated ozone losses (after the described conflict) of 25-45 percent above mid-latitudes and 50-70 percent above northern high latitudes persisting for five years, with substantial losses continuing for another five years. Such severe ozone depletion would allow intense levels of harmful ultraviolet light to reach Earth’s surface–even with the stratospheric smoke layer in place.”
How much can we count on enlightened self-interest to protect us from a nuclear disaster? This discourages states from deliberately starting a nuclear war, but makes triggering such a war a tempting and easy target for any crazy person or group who actively wants to destroy civilization. And there remains the ongoing prospect of an accidental conflagration, aptly demonstrated by a series of near misses over the last 50 years.
Tagged: existential risk, nuclear
