While global warming looms large as a serious threat, a leading physicist visiting Sydney this week says we should be just as concerned about the catastrophe that would result from widespread global cooling following a nuclear war.
Steven Starr, a Senior Scientist with Physicians for Social Responsibility based at the University of Missouri, will be speaking this Friday 31 July at the University of Sydney about the dangers presented by the world's 23,000 warheads.
"In a nuclear war, burning cities would create millions of tons of thick, black smoke," says Starr. "This smoke would rise above cloud level, into the stratosphere, where it would quickly spread around the planet."
Starr, a leading world authority on the danger of nuclear winter, says the smoke created by a large nuclear war would block most sunlight from reaching the Earth's surface, rapidly creating Ice Age temperatures on Earth.
"The cold would last a long time; NASA computer models predict 40 per cent of the smoke would still remain in the stratosphere10 years after a nuclear war."
Just half of one per cent of the explosive power of US-Russian nuclear weapons can create enough darkness to impact global climate, Starr warns. Northern Hemisphere temperature falls would lead to shorter growing seasons, causing up to 1 billion people to starve to death.
Starr is in Sydney as a guest at the University of Sydney's Centre for Peace and Conflict Studies. He is working with Sydney University's Professor Peter King to lobby the International Commission on Nuclear Non-Proliferation and Disarmament, an Australian Government initiative chaired by Gareth Evans.
"It can never be in the interest of a nuclear power, let alone humanity, to carry out a retaliatory deterrent threat against a nuclear-armed opponent", says King, a Research Associate in Government and International Relations at the University of Sydney.