The Doomsday Clock has jumped closer to midnight than it's ever been in its 73-year history, indicating looming apocalyptic threats.

The clock is a symbol created at the dawn of the Cold War. Its time is set annually by the Bulletin of the Atomic Scientists, a group founded by researchers who helped build the first nuclear weapons during the Manhattan Project.

The Bulletin began publicly adjusting the clock in 1947 to reflect the state of dire threats to the world. At first, they were primarily addressing tense US-Soviet relations and the risk for global nuclear war.

But since 1991, the clock has taken into account other major threats such as climate change and cyberwarfare.

"The Doomsday Clock is a globally recognised indicator of the vulnerability of our existence," Mary Robinson, former president of Ireland and former UN High Commissioner for Human Rights, said in a press briefing about the clock's time change on Thursday.

"It's a metaphor backed by rigorous scientific scrutiny. This is no mere analogy. We are now 100 seconds to midnight, and the world needs to wake up."

Previously, the clock's most alarming position was two minutes to midnight, where it sat in 2018 and 2019 for the first time since 1953. On Thursday, researchers moved it 20 seconds closer, citing a rising risk of global conflict and the looming threat of climate change.

"What we have called the new abnormal last year – an abysmal state of affairs in the realms of nuclear security and climate change – now has become an apparently enduring, disturbing reality in which things are not getting better," Robert Rosner, chair of the Bulletin's Science and Security Board, said in the briefing.

"We have indeed normalized a very dangerous world."

Members of the Bulletin chastised world leaders, particularly President Donald Trump, for not leading a charge against nuclear weapons, fossil-fuel emissions, and the spread of misinformation.

"Citizens around the world should rightfully echo the words of climate activist Greta Thunberg and ask, 'How dare you'," Bulletin president and CEO Rachel Bronson said, referring to a tearful speech in which the 16-year-old activist scolded world leaders at the UN Climate Action Summit in September 2019.

Former California Gov. Jerry Brown added, "we are truly in a dangerous moment, but you would never know that from the president, from the Republican leadership, or even from the Democratic leadership. What is being said this morning is not being heard. It's being ignored, it's being denied, and it's being belittled."

Why the Doomsday Clock is closer to midnight than ever

Researchers said they chose the clock's new position before the Trump administration announced that it had killed Iranian general Qassem Soleimani. Rising concerns about Iran developing nuclear weapons, the Bulletin researchers said, further support their decision.

"It seems the world is a pressure cooker," Robert Latiff, an expert on military technology, said. "It is a high-energy system that only requires a simple mistake, somewhere in a world bristling with weapons, for a war to start and escalate catastrophically."

The Bulletin members compared the state of today's international relations to the fragile nuclear landscape of the Cold War. They cited the failure of US negotiations with North Korea, the possibility that the Iran nuclear deal could fall apart, and continued tensions between India and Pakistan – all of which could lead to nuclear conflict.

Other military technologies also concern the Bulletin scientists, including artificial-intelligence systems, experiments with pathogens, and hypersonic weapons.

"We have a witch's brew of ingredients for global conflict," Latiff said.

Meanwhile, global temperatures are rising as fossil-fuel use pumps heat-trapping gas into the atmosphere. Last year was the second-hottest on record.

The spike in temperatures has been linked to the rising frequency and intensity of heat waves, wildfires, hurricanes, and floods – events that all broke records in 2019.

"Despite these devastating warnings, and although some governments are echoing scientists' use of the term 'climate emergency,' their policies are hardly commensurate of an emergency," Sivan Kartha, a climate scientist working with the Intergovernmental Panel on Climate Change, said.

He pointed to world leaders' failure to come away from global climate meetings with concrete plans; the December COP25 summit in Madrid was widely criticised for yielding few tangible outcomes.

"To test the limits of Earth's habitable temperature is madness. It's a madness akin to the nuclear madness that is again threatening the world," Kartha said.

The researchers added that the spread of misinformation makes it more difficult to pursue solutions.

"The continued use in 2019 of untruths, exaggerations, and misrepresentations by world leaders, in response to what they deem 'fake news,' has made worse an already dangerous situation," Latiff said.

Time is running out to turn the clock back

Critics of the Doomsday Clock have questioned its usefulness in recent years, with some arguing that the apocalyptic analysis can paralyse people and foster inaction. Others say the clock is not scientific, while some critics question the Bulletin's authority on policy solutions.

"The Doomsday Clock unscientific," Lawrence Krauss, a theoretical physicist and former Bulletin board member, wrote in a Wall Street Journal op-ed on Wednesday.

"The factors of its setting are now dominated more by policy questions than scientific ones. The former may be important, but claiming the authority of 'atomic scientists' is appropriate only for the latter."

But Brown defended the Bulletin on Thursday.

"Speaking of danger and destruction is never very easy. If you speak the truth, people will not want to listen because it's too awful and it makes you sound like a crackpot," he said.

The Bulletin members did note, however, that there is still time to calm nuclear tensions and slow climate change – if world leaders cooperate.

"The world is not over. We have incredible opportunity to reverse the nuclear arms race, the carbon emissions, and the headlong rush to ever more dangerous technology," Brown said. "It's within human hands."

This article was originally published by Business Insider.

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