According to a group of elite nuclear scientists, the world has moved closer to Armageddon.

The scientists have moved the minute hand of the Doomsday Clock closer to midnight to reflect the growing concerns of global terrorism, the unchecked nuclear ambitions of Iran and North Korea and -- in a first -- the threat of climate change.

The clock was first set 60 years ago by an elite group of nuclear scientists at the Bulletin of the Atomic Scientists, shortly after the United States dropped its atomic bombs on Japan. It was meant to symbolize the perils facing humanity from nuclear weapons.

But for the first time, the clock is also registering the threat of global warming, which they call a "second nuclear age."

The clock, which hangs in the University of Chicago, has been set at seven minutes to midnight since 2002. It was moved Wednesday to five minutes before the hour.

"The dangers posed by climate change are nearly as dire as those posed by nuclear weapons," the scientists said in a statement.

"The effects may be less dramatic in the short term than the destruction that could be wrought by nuclear explosions, but over the next three to four decades climate change could cause irremediable harm to the habitats upon which human societies depend for survival."

The scientists also took issue with North Korea's recent test of a nuclear weapon, Iran's nuclear ambitions, and the continued presence of some 26,000 nuclear weapons in the United States and Russia.

"Not since the first atomic bombs were dropped on Hiroshima and Nagasaki has the world faced such perilous choices," the scientist said in a statement.

John Polanyi, the 1986 Nobel Prize winner for chemistry and the Canadian chair of the Pugwash Group, tells CTV Newsnet that he finds the missiles that the U.S. has trained on Russia and the ones that Russia has in kind to be particularly disturbing, if not puzzling.

"There is no justification for having them. The Cold War, of which they are a relic, is now at least 16 years in the past," he says.

"It is an incredible failure of imagination and an incredible irresponsibility, really, not to have removed those weapons. "

He says the U.S. is being illogical when it condemns countries such as North Korea for testing its nuclear weapons.

"You can't at the same time say 'we need weapons for frivolous reasons' and then say to new nations that want to get these weapons, 'don't get them, they are a danger to you, your are safer without them'."

The Bulletin of the Atomic Scientists was founded by former Manhattan Project scientists who turned against nuclear weapons after developing the first atomic bomb.

Since 1947, its Doomsday clock's minute hand has been moved 18 times. Some key years:

• 1953: Set at two minutes before midnight -- its closest proximity to doom -- after the United States and the Soviet Union detonated hydrogen bombs.
• 1991: Moved to its furthest point from doom -- 17 minutes to midnight -- when a new global nuclear arms treaty was signed.
• 2002: Set at seven minutes before midnight, a few months after 9/11 and after the United States withdrew from the Anti-Ballistic Missile Treaty.

The decision to move the minute hand is made by the Bulletin's Board of Directors in consultation with its board of sponsors, which include Stephen Hawking and 18 Nobel laureates.