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Nuclear autumn

13 October 2008

Cosmos Online


The Cold War may be over, but even a relatively small nuclear exchange by rogue nations or terrorist groups could wreak havoc on global climate, threatening civilisation as we know it.


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Credit: U.S. Department of Energy

In 1983, a team of scientists spearheaded by the late Carl Sagan became concerned about the long-term effects of a nuclear exchange between the U.S. and Soviet Union. They concluded that, devastating as they were, the bombs wouldn't be what destroyed civilisation as we knew it.

That dubious honour, they calculated, belonged to the years-long 'nuclear winter' that would result from soot and smoke darkening the sun and plunging temperatures to below freezing across much of the globe.

With the end of the Cold War, the risk of all-out nuclear war receded, and so, it seemed, did the risk of nuclear winter. But the relief may have been premature, scientists say.

In a series of papers presented in San Francisco, at a December 2006 meeting of the American Geophysical Union (and subsequently published in Science), a group that included two members of the original nuclear-winter team (Richard Turco and Owen Toon) re-examined the effects of nuclear bomb blasts.

They found that even a small nuclear exchange between rising nuclear powers such as India and Pakistan would radically affect the Earth's climate. The result wouldn't be a full-fledged nuclear winter, but their simulations nevertheless showed that such a war would wreck the Earth's ozone layer and initiate a global "nuclear autumn" that would cause years of crop failures, famine, and panic.

Booming cities

The threat stems from the fact that if you're a small nuclear power with a serious grudge against a neighbour, you're likely to use your arsenal primarily against cities. And it turns out that for this purpose, the monstrous megaton-scale bombs the U.S. and USSR once aimed at each other are "simply overkill," says Turco, an atmospheric scientist at the University of California, Los Angeles.

The risk is compounded by the fact that everywhere, people are flocking to cities, many in politically unstable regions. "We're growing megacities all over the world," says Owen Toon, an atmospheric scientist at the University of Colorado at Boulder. "Tehran has 10 million people."

These cities are so densely packed that the scientists estimate 20 million people could be killed outright in a war between India and Pakistan – even if each side used as few as 50 Hiroshima-sized bombs. That's nearly as many people as died in World War II, and comparable to the number of casualties once predicted from some scenarios for an all-out war between the U.S. and the USSR.

Readers' comments

Invention Of The Atomic Bomb

The Orchestration of esembling the scientific devive that would split the atom for destruction, is no small feat. Even in the 1940's was early for western man, to grasp such a weapon- it is plausible to think how it really came into being- Why would the nature of Man, and his inborn hate wish such a disaster, on Humankind? Answer that someone, Then maybe it will be realized that there really is more to this Universe, than just- people who just can't seem to get along.It has been sometimenow that the response of the United States has leveled the conciousness of our Enemies- Who Will learn from the out-come of the next insanity.

India and nuclear armament

INDIA AND NUCLEAR ARMAMENT
By Allama Muhammad Yousaf Gabriel
DEAR SIR,
Indians writers regard the nuclear threat as a universal threat to all life on earth, and negate the efficacy of the Nuclear Non-proliferation Treaty, and although they discuss at length the nuclear war strategies, preparations, precautions, tactics of nuclear assault and defense, yet it clearly appears that a sense of regret and the factor of exigency and helplessness constantly pervades their mind. Dr.Ashoke Kapur, an Indian by birth and a Professor of Political Science in the Waterloo University of Canada, wants India to go head-long into the nuclear armament, without so much as a mention of the nuclear hazards, not only in reference to Indo-Pak nuclear conflict but in the international perceptive without any fear of atomic war, because the atomic weapons are made not to use them but rather are a show of power and a means of political influence. The Professor of Waterloo University, appears to win the Indo-Pak nuclear-Waterloo as well as the Waterloo of Interntional Politics with one dire yell, forgetting that he did not stand in the. field of ancient Mahabharat exhorting the Charriot-ridden warriors to victory, but rather twisted the tails of fiery nuclear war demons of twentieth century. Such a machmohan of Mahabharat could neither be regarded as a friend of India, nor a votary of world peace. Applause he might have from the Hawks of India, but there are millions in India, like General Duhra and others who hate atomic bombs, but will they be heard. They may be roasted, alive in the atomic fire, along with the hawks innocently.
Allama Muhammad Yousuf Gabriel,
Adara Afqare Gabriel, QA Street Nawababad Wah Cantt.Distt RAwalpindi Pakistna
Yousuf_gabriel@yahoo.com
www.oqasa.org