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The Doomsday Clock has been ticking for 76 years. But it is no ordinary clock.
It tries to gauge how close humanity is to destroying the world.
On Tuesday, the clock was set to 90 seconds to midnight — the closest to the hour it’s ever been, according to the Bulletin of the Atomic Scientists, who created the clock in 1947. Midnight represents the moment when we will have made the Earth uninhabitable for humanity. From 2020 to 2022, the clock was set to 100 seconds to midnight.
The clock is not designed to definitively measure existential threats, but rather to spark conversations about difficult science topics such as climate change, the Bulletin said.
The decision to move the clock forward 10 seconds this year is largely due to the Russian invasion of Ukraine and the increased risk of nuclear escalation, the Bulletin said in a press release. The lingering threats of the climate crisis, as well as the breakdown of norms and institutions necessary to mitigate risks from biological threats such as Covid-19, also played a role.
“We live in a time of unprecedented danger, and the Doomsday Clock time reflects that reality,” Rachel Bronson, president and CEO of the Bulletin, said in the release. “It is a decision that our experts do not take lightly. The US government, its NATO allies and Ukraine have a wide variety of channels for dialogue; we are urging leaders to explore each as best they can to turn back the clock.”
The Bulletin of the Atomic Scientists was founded by a group of atomic scientists who worked on the Manhattan Project, the codename for the development of the atomic bomb during World War II.
The organization was originally set up to measure nuclear threats, but in 2007 the Bulletin made the decision to include climate change in its calculations.
Over the past three-quarters of a century, the clock’s time has changed in accordance with how close scientists believe humanity is to utter destruction. Some years time changes, and some years it doesn’t.
The Doomsday Clock is set each year by the experts of the Bulletin’s Science and Security Board in consultation with the Board of Sponsors, including 11 Nobel laureates.
While the clock has been an effective wake-up call when it comes to reminding people of the successive crises facing the planet, some have questioned the usefulness of the 75-year-old clock.
“It’s an imperfect metaphor,” Michael E. Mann, presidential distinguished professor in the Department of Earth and Environmental Sciences at the University of Pennsylvania, told CNN in 2022, emphasizing that the clock’s framing combines different types of risks that represent different have characteristics and occur in different time scales. Still, he adds, it “remains an important rhetorical device that reminds us year after year of the frailty of our current existence on this planet.”
Each model has limitations, Eryn MacDonald, an analyst with the Union of Concerned Scientists’ Global Security Program, told CNN in 2022.
“While I wish we could talk about minutes to midnight again instead of seconds, unfortunately that no longer reflects reality,” she said.
The clock has never reached midnight and Bronson hopes it never will.
“If the clock is midnight, it means that some kind of nuclear exchange or catastrophic climate change has occurred that wiped out humanity,” she said. “We never really want to get there and we won’t know if we do.
The clock’s time is not intended to measure threats, but rather to spark conversation and encourage public engagement on scientific topics such as climate change and nuclear disarmament.
If the clock can do that, Bronson considers it a success.
When a new time is put on the clock, people listen, she said. At the COP26 climate talks in Glasgow, UK, in 2021, former Prime Minister Boris Johnson cited the Doomsday Clock when speaking about the climate crisis facing the world, Bronson noted.
Bronson said she hopes people will discuss whether they agree with the Bulletin’s decision and have fruitful conversations about what are the drivers behind the change.
Moving turning back the clock with bold, concrete actions is still possible. In fact, the hand moved the furthest from midnight – a whopping 17 minutes to the hour – in 1991, then The administration of President George HW Bush signed the Strategic Arms Reduction Treaty with the Soviet Union. In 2016, the clock was set to three minutes to midnight as a result of the nuclear deal with Iran and the Paris climate agreement.
“We at Bulletin believe that because humans have created these threats, we can mitigate them,” Bronson said. “But that’s not easy, and it never has been. And it requires serious work and global involvement at all levels of society.”
Don’t underestimate the power of talking about these important issues with your colleagues, Bronson said.
“You may not feel it because you’re not doing anything, but we know that public engagement moves (a) leader to do things,” she said.
To make a positive impact 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 driving and how your house is heated, Bronson explained.
Eating seasonally and locally, reducing food waste and recycling properly are other ways to mitigate or address the impacts of the climate crisis.