The Doomsday Clock reveals how close humanity may be to total annihilation

On Tuesday, the clock was set at 89 seconds to midnight — the closest the world has ever been to the marker that represents the moment at which people will have made the Earth uninhabitable.

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(CNN) — Seventy-eight years ago, scientists created a unique sort of timepiece — named the Doomsday Clock — as a symbolic attempt to gauge how close humanity is to destroying the world.

On Tuesday, the clock was set at 89 seconds to midnight — the closest the world has ever been to that marker, according to the Bulletin of the Atomic Scientists, which established the clock in 1947. Midnight represents the moment at which people will have made the Earth uninhabitable.

For the two years prior, the Bulletin set the clock at 90 seconds to midnight mainly due to Russia’s invasion of Ukraine, the potential of a nuclear arms race, the Israel-Hamas conflict in Gaza, and the climate crisis.

The clock isn’t designed to definitively measure existential threats but rather to spark conversations about difficult scientific topics such as climate change, according to the Bulletin.

“We set the clock closer to midnight because we do not see sufficient, positive progress on the global challenges we face, including nuclear risk, climate change, biological threats and advances in disruptive technologies” such as artificial intelligence, said Daniel Holz, the Bulletin’s science and security board chair and professor in the department of physics, astronomy and astrophysics at the University of Chicago, in a news briefing Tuesday. “The countries that possess nuclear weapons are increasing the size and role of their arsenals, investing hundreds of billions of dollars in weapons that can destroy civilization many times over.”

Progress in the development of “disruptive technologies,” such as artificial intelligence, biotechnology and in space has also far outpaced regulation in those areas, Holz added.

“All of these dangers are greatly exacerbated by a potent threat multiplier — the spread of misinformation, disinformation and conspiracy theories that degrade the communication ecosystem and increasingly blur the line between truth and falsehood,” Holz added.

What is the Doomsday Clock?

The Bulletin of the Atomic Scientists was founded by a group of scientists who worked on the Manhattan Project, the code name for the development of the atomic bomb during World War II.

Originally, the organization was conceived to measure nuclear threats, but in 2007 the Bulletin made the decision to include climate change in its calculations.

Over the last 78 years, the clock’s time has changed according to how close scientists believe the human race is to total destruction. Some years the time changes, and some years it doesn’t.

The Doomsday Clock is set every year by experts on the Bulletin’s Science and Security Board in consultation with its Board of Sponsors, which was first established by Albert Einstein in December 1948, with J. Robert Oppenheimer as its first chair. The board currently includes nine Nobel laureates, many of them in physics, physiology or medicine.

The clock has been an effective wake-up call when it comes to reminding people about the cascading crises the planet is facing, but some have questioned its usefulness.

“It’s an imperfect metaphor,” Michael E. Mann, Presidential Distinguished Professor in the earth and environmental science department at the University of Pennsylvania, told CNN in 2022, highlighting that the clock’s framing combines various types of risk that have different characteristics and occur in different timescales. Still, he added that it “remains an important rhetorical device that reminds us, year after year, of the tenuousness of our current existence on this planet.”

Every model has constraints, Eryn MacDonald, an analyst with the Union of Concerned Scientists’ Global Security Program, told CNN in 2022, adding that the Bulletin has made thoughtful decisions each year on how to get people’s attention about existential threats and the required action.

“While I wish we could go back to talking about minutes to midnight instead of seconds, unfortunately that no longer reflects reality,” MacDonald said.

What happens if the clock reaches midnight?

The clock has never reached midnight, and Bulletin president and CEO Rachel Bronson said she hopes it never will.

“When the clock is at midnight, that means there’s been some sort of nuclear exchange or catastrophic climate change that’s wiped out humanity,” she said. “We never really want to get there, and we won’t know it when we do.”

How accurate is the clock?

Though the clock can’t measure threats, if it sparks conversation and encourages public engagement in scientific topics such as climate change and nuclear disarmament, then Bronson views it as a success.

When a new time is set on the clock, people listen, she said. At the UN Climate Change Conference in Glasgow, Scotland in 2021, then-UK Prime Minister Boris Johnson cited the Doomsday Clock when talking about the climate crisis the world is facing, Bronson noted.

Bronson said she hopes people will discuss whether they agree with the Bulletin’s decision and have fruitful talks about what the driving forces of the change are.

Moving the clock back with bold, concrete actions is still possible. In fact, the hand moved the farthest away from midnight — a whopping 17 minutes before the hour — in 1991, when then-President George H.W. Bush’s administration signed the Strategic Arms Reduction Treaty with the Soviet Union.

What can individuals do to turn back time on the clock?

“We at the Bulletin believe that because humans created these threats, we can reduce them,” Bronson said. “But doing so is not easy, nor has it ever been. And it requires serious work and global engagement at all levels of society.”

Don’t underestimate the power of talking about these important issues with your peers, Bronson said.

“You might not feel it because you’re not doing anything, but we know that public engagement moves (a) leader to do things,” she said.

Personal actions can make a difference. To have a positive impact on climate change, look at your daily habits and see if there are small changes you can make in your life such as how often you walk versus drive and how your home is heated, Bronson said.

Eating seasonally and locally, reducing food waste, conserving water and recycling properly are other ways to help mitigate, or deal with the effects of, the climate crisis.

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