In 2024, humanity edged ever closer to catastrophe. Trends that have deeply concerned the Science and Security Board continued, and despite unmistakable signs of danger, national leaders and their societies have failed to do what is needed to change course. Consequently, we now move the Doomsday Clock from 90 seconds to 89 seconds to midnight—the closest it has ever been to catastrophe. Our fervent hope is that leaders will recognize the world’s existential predicament and take bold action to reduce the threats posed by nuclear weapons, climate change, and the potential misuse of biological science and a variety of emerging technologies.

In setting the Clock one second closer to midnight, we send a stark signal: Because the world is already perilously close to the precipice, a move of even a single second should be taken as an indication of extreme danger and an unmistakable warning that every second of delay in reversing course increases the probability of global disaster.

In regard to nuclear risk, the war in Ukraine, now in its third year, looms over the world; the conflict could become nuclear at any moment because of a rash decision or through accident or miscalculation. Conflict in the Middle East threatens to spiral out of control into a wider war without warning. 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. The nuclear arms control process is collapsing, and high-level contacts among nuclear powers are totally inadequate given the danger at hand. Alarmingly, it is no longer unusual for countries without nuclear weapons to consider developing arsenals of their own—actions that would undermine longstanding nonproliferation efforts and increase the ways in which nuclear war could start.

The impacts of climate change increased in the last year as myriad indicators, including sea-level rise and global surface temperature, surpassed previous records. The global greenhouse gas emissions that drive climate change continued to rise. Extreme weather and other climate change-influenced events—floods, tropical cyclones, heat waves, drought, and wildfires—affected every continent. The long-term prognosis for the world’s attempts to deal with climate change remains poor, as most governments fail to enact the financing and policy initiatives necessary to halt global warming. Growth in solar and wind energy has been impressive but remains insufficient to stabilize the climate. Judging from recent electoral campaigns, climate change is viewed as a low priority in the United States and many other countries.

In the biological arena, emerging and re-emerging diseases continue to threaten the economy, society, and security of the world. The off-season appearance and in-season continuance of highly pathogenic avian influenza (HPAI), its spread to farm animals and dairy products, and the occurrence of human cases have combined to create the possibility of a devastating human pandemic. Supposedly high-containment biological laboratories continue to be built throughout the world, but oversight regimes for them are not keeping pace, increasing the possibility that pathogens with pandemic potential may escape. Rapid advances in artificial intelligence have increased the risk that terrorists or countries may attain the capability of designing biological weapons for which countermeasures do not exist.

An array of other disruptive technologies advanced last year in ways that make the world more dangerous. Systems that incorporate artificial intelligence in military targeting have been used in Ukraine and the Middle East, and several countries are moving to integrate artificial intelligence into their militaries. Such efforts raise questions about the extent to which machines will be allowed to make military decisions—even decisions that could kill on a vast scale, including those related to the use of nuclear weapons. Tensions among the major powers are increasingly reflected in competition in space, where China and Russia are actively developing anti-satellite capabilities; the United States has alleged that Russia has tested a satellite with a dummy warhead on it, suggesting plans to place nuclear weapons in orbit.

The dangers we have just listed 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. Advances in AI are making it easier to spread false or inauthentic information across the internet—and harder to detect it. At the same time, nations are engaging in cross-border efforts to use disinformation and other forms of propaganda to subvert elections, while some technology, media, and political leaders aid the spread of lies and conspiracy theories. This corruption of the information ecosystem undermines the public discourse and honest debate upon which democracy depends. The battered information landscape is also producing leaders who discount science and endeavor to suppress free speech and human rights, compromising the fact-based public discussions that are required to combat the enormous threats facing the world.

Blindly continuing on the current path is a form of madness. The United States, China, and Russia have the collective power to destroy civilization. These three countries have the prime responsibility to pull the world back from the brink, and they can do so if their leaders seriously commence good-faith discussions about the global threats outlined here. Despite their profound disagreements, they should take that first step without delay. The world depends on immediate action.

It is 89 seconds to midnight.

Editor’s note: Additional information on the threats posed by nuclear weapons, climate change, biological events, and the misuse of other disruptive technologies can be found elsewhere on this page and in the full PDF / print version of the Doomsday Clock statement.