(CN) - Humankind remains stuck at three minutes to "midnight" on the Bulletin of Atomic Scientists' Doomsday Clock - a chilling barometer of the threat to "the very existence of civilization," the scientists said Tuesday.
Founded in 1945 by a group of Manhattan Project scientists who "could not remain aloof to the consequences of their work," the Bulletin of Atomic Scientists first launched the Doomsday Clock in 1947 as a way to convey the threat nuclear proliferation poses to humanity to both world leaders and the public.
That year, the group set the clock to seven minutes to midnight - a metaphorical 420 seconds to the end of human existence.
By 1949, the Soviets had tested their first nuclear device and humanity inched four minutes closer to our demise with the start of the arms race. In 1953, both the United States and the Soviet Union had detonated their first hydrogen bombs and the Doomsday Clock moved closer to midnight than ever before or since: two minutes till.
Since then, the hands of the clock have moved backward and forward depending on the state of the world and the various attempts at nuclear treaties.
In 1984, the deep freeze in U.S.-Soviet relations moved the clock to three minutes to midnight. But the end of the Cold War and the hope it brought to humanity moved the hands of the clock to 17 minutes before midnight in 1991 - the farthest it's ever been from doomsday.
But each passing year after 1991 has pushed the clock back toward midnight amid fears of a nuclear Pakistan and India, broken treaties, weapons testing in North Korea and Iran and missing weapon-grade nuclear material that could end up in the hands of terrorists.
The scientists added climate change to the list of worries for our existence in 2007, and set the clock at five minutes to midnight. In 2015 - amid global nuclear weapons modernization and a warming earth that shows no signs of abating - the group set the Doomsday Clock to three minutes to midnight.
On Tuesday, the group left the clock unchanged.
"The Iran nuclear agreement and the Paris climate accord are major diplomatic achievements, but they constitute only small bright spots in a darker world situation full of potential for catastrophe," the group said in a statement.
Noting that tensions between the United States and Russia have become Cold War-like - and fearing that the Paris climate-change agreement may be too little, too late - the group found "the world situation to be highly threatening to humanity - so threatening that the hands of the Doomsday Clock must remain at three minutes to midnight, the closest they've been to catastrophe since the early days of above-ground hydrogen bomb testing."
The scientists chastised world leaders for having undone all the hope brought by the end of the Cold War in the 1990s.
"Three minutes is too close. Far too close. We, the members of the science and security board of the Bulletin of the Atomic Scientists, want to be clear about our decision not to move the hands of the Doomsday Clock in 2016: That decision is not good news, but an expression of dismay that world leaders continue to fail to focus their efforts and the world's attention on reducing the extreme danger posed by nuclear weapons and climate change.
"When we call these dangers existential, that is exactly what we mean: They threaten the very existence of civilization and therefore should be the first order of business for leaders who care about their constituents and their countries."
The scientists called on world leaders to reduce spending on nuclear modernization programs, start disarmament negotiations, talk to rather than isolate North Korea, and bolster the Paris climate accord with actions that will truly reduce greenhouse gas emissions.
"Last year, the board moved the Doomsday Clock forward to three minutes to midnight, noting 'the probability of global catastrophe is very high, and the actions needed to reduce the risks of disaster must be taken very soon,'" the scientists said. "That probability has not been reduced. The Clock ticks. Global danger looms. Wise leaders should act - immediately."
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