The Doomsday Clock has crept to 90 seconds before midnight this year, the closest it has ever been to the metaphorical hour of Armageddon since it was created shortly after the advent of nuclear weapons.

The clock had remained frozen for two years at 100 seconds to midnight, which itself was an all-time danger mark. But Russia’s invasion of Ukraine in February was the main factor in the hand ticking 10 seconds closer to the hour of doom.

Russian President Vladimir Putin compounded this aggressive action by threatening to unleash nuclear weapons if the U.S. or NATO countries directly intervened, raising a grim specter of nuclear holocaust not seen since the Cold War.

In setting the time, the Bulletin of the Atomic Scientists, which created the clock in 1947, considered nuclear threats, climate change, disruptive technologies that might be used in cyberattacks, the spread of disinformation and the risk of deadly outbreaks such as the coronavirus pandemic.

In an email, the leader of a nuclear watchdog group said the organization agreed with scientists nudging the clock’s hand closer to the brink, given the perils between the world’s nuclear powers continue to grow.

“Each of the nine countries with nuclear weapons, including the United States, continues spending more and more for inherently indiscriminate nuclear weapons that should not have a place in modern warfare,” wrote former U.S. Rep. John Tierney, who’s now executive director of the Council for a Livable World. “Russia’s words and actions further fuel the crisis and could provoke an arms race for decades to come. As the clock’s movement toward midnight signals, we are all heading rapidly in the wrong direction.”

The nuclear threat coupled with the escalating effects of climate change make the danger seem more immediate, Tierney added.

Los Alamos National Laboratory is tied to the clock, both historically and in its plans to make 30 plutonium pits a year by 2026 to trigger nuclear warheads. At the same time, the Savannah River Site in South Carolina is gearing up to make 50 additional pits by the mid-2030s.

Some officials insist the new bomb cores are needed to modernize an aging nuclear stockpile, while critics denounce the effort as fueling an arms race with political adversaries such as China, Russia and Iran.

The Bulletin of the Atomic Scientists was created by physicists involved in the Manhattan Project based at Los Alamos, once a secret enclave where a team worked to develop the atomic bombs that were dropped on Hiroshima and Nagasaki, Japan, during World War II.

The physicists, concerned about the bombs’ destructive force, devised the clock.

The hand moves toward or away from midnight according to global hazards. It was placed at 11:58 in the early 1950s, when the U.S. and the Soviets developed hydrogen bombs, heightening Cold War tensions.

It was as far away from midnight as 17 minutes when the Cold War ended in 1991 and the two superpowers signed arms treaties and began cutting their nuclear arsenals. That détente now seems a passing moment in the distant past, as Putin wages war in Ukraine and looks to revive some of the former Soviet empire.

For 60 years, the clock gauged nuclear dangers. Since 2007, climate change, disruptive technologies, disinformation and the coronavirus pandemic have been added.

The war in Ukraine has wreaked havoc on the world’s energy market, causing gas prices to spike. The trend has led to long-term investments in renewable energy but also has spurred a push for countries to develop and export more natural gas to fill the gap and capitalize on the higher prices, the Bulletin of the Atomic Scientists posted on its website.

The result is record-high carbon dioxide emissions worldwide at a time when scientists are sounding the alarm about the catastrophic effects of not quelling climate change.

Another byproduct of war is increased international unease that thwarts the collaboration needed to make headway in countering climate change, the bulletin wrote.

Meanwhile, online-enabled disinformation flowed unabated, hampering efforts to combat climate change and the coronavirus pandemic. Social media became more infested with purveyors of false information and conspiracy theorists.

One bright spot is that most U.S. voters rejected election deniers, and President Joe Biden is consulting with scientists for public policy, the bulletin wrote. So, overall, battles were won and lost regarding disinformation.

Scientists say the clock’s purpose is less about precisely gauging dangers than it is to start conversations about how to reduce them.

Tierney wrote it’s crucial for world leaders to posture less and talk to each other more — even if they’re adversaries — about ratcheting down nuclear arsenals and forging nonproliferation treaties.

“Humans created the problems of nuclear weapons and climate change, and humans can fix them,” he wrote. “Until we turn toward these solutions, humankind will continue lurching ever closer to symbolic midnight.”