Doomsday Clock Set at 90 Seconds to Midnight

The 2023 Doomsday Clock statement details other threats and threat multipliers beyond the most immediate risks related to the Russia-Ukraine War. Among these threats:

Nuclear Weapons

·  The last remaining nuclear weapons treaty between Russia and the United States, New START, stands in jeopardy. Unless the two parties resume negotiations and find a basis for further reductions, the treaty will expire in February 2026. This would eliminate mutual inspections, deepen mistrust, spur a nuclear arms race, and heighten the possibility of a nuclear exchange.

·  China’s considerable expansion of its nuclear capabilities is particularly troubling, given its consistent refusal to consider measures to enhance transparency and predictability. The US Defense Department claims Beijing may increase its arsenal fivefold by 2035 and could soon rival the nuclear capabilities of the United States and Russia, with unpredictable consequences for stability.

·  North Korea has greatly stepped up its intermediate and longer-range missile testing. In late March, North Korea successfully launched an intercontinental ballistic missile for the first time since 2017. In the following months, it also launched numerous other ballistic missiles, most of short range. Perhaps most concerning, on October 4, North Korea launched an intermediate-range ballistic missile over Japan. Meanwhile, US officials contend that North Korea is preparing to conduct its seventh nuclear weapon test.

·  Iran continues to increase its uranium enrichment capacity, albeit under international safeguards outside the confines of the Joint Comprehensive Plan of Action that once restrained it. This positions Iran closer to a nuclear weapons capability, should it decide to cross that threshold. Returning to the nuclear deal would reduce risks and provide a path forward, and the United States, Europe, and other countries have made reasonable efforts to revive the deal. But instability in Iran and Tehran’s support for Russia’s war against Ukraine will complicate successful negotiations to keep Iran from acquiring nuclear weapons.

·  India continues to modernize its nuclear arsenal of some 160 warheads, with new delivery systems now under development to complement or replace existing nuclear-capable aircraft, land-based delivery systems, and sea-based systems. Pakistan has an arsenal of similar size and continues to expand its warheads, delivery systems, and fissile material production.

·  The United States, Russia, and China are now pursuing full-fledged nuclear weapons modernization programs, setting the table for a dangerous new “third nuclear age” of competition. Long-standing concerns about arms racing in South Asia and missile arms races in Northeast Asia complete a dismal picture that needs to be addressed.

Climate Crisis

·  The Russia-Ukraine War’s effects are not limited to an increase in nuclear danger; they also undermine global efforts to combat climate change. Countries dependent on Russian oil and gas have sought to diversify their supplies and suppliers, leading to expanded investment in natural gas exactly when such investment should have been shrinking.

·  Global carbon dioxide emissions from burning fossil fuels, after having rebounded from the COVID economic decline to an all-time high in 2021, continued to rise in 2022 and hit another record high. A decline in Chinese emissions was overshadowed by a rise in the US, India, and elsewhere.

·  Not only did weather extremes continue to plague diverse parts of the globe, but they were more evidently attributable to climate change. Countries of West Africa experienced floods that were among the most lethal in their histories, owing to a rainfall event that was assessed to be 80 times more likely because of climate change. Extreme temperatures in Central Europe, North America, China, and other regions of the Northern Hemisphere this past summer led to water shortages and soil drought conditions that led in turn to poor harvests, further undermining food security at a time when the Ukraine conflict has already driven food price increases. Pakistan faced intense floods due to a “monsoon on steroids” that inundated one-third of the country, affecting 33 million people directly and unleashing cascading effects, including a major crop failure, an epidemic of water-borne diseases, and the destruction of infrastructure, homes, livestock, and livelihoods.


·  Devastating events like the COVID-19 pandemic can no longer be considered rare, once-a-century occurrences. The total number and diversity of infectious disease outbreaks has increased significantly since 1980, with more than half caused by zoonotic diseases (that is, disease originating in animals and transmitted to humans). As such, zoonoses put the human population at significant risk for pandemics. There is immense, uncharacterized diversity within the 26 virus families and the many phyla of bacteria and other microbes known to infect humans. The world’s ability to predict which of these viruses and microbes are most likely to cause human disease is woefully inadequate.

·  Laboratory accidents continue to occur frequently. Opportunities for human error, limited understanding of novel disease characteristics, lack of local government knowledge about the types of research occurring in labs in their jurisdictions, and confusion about lab safety requirements all challenge current laboratory biosafety and biosecurity programs. It is also easier now than ever to obtain and modify pathogens, increasing the chances of pandemics caused by laboratory accidents.

·  Recent events—including especially the Russian invasion of Ukraine and its continuing disinformation efforts in regard to biological weapons—have changed the landscape of biological threats. The risk that Russia will engage in biological warfare increases as conditions in Ukraine become more chaotic, weakening norms of warfare. Escalation of the war in Ukraine poses many potentially existential threats to humanity; one of them is biological.

Disinformation and Disruptive Technology

·  Inside Russia… government control of the information ecosystem has blocked the wide dissemination of truthful information about the Ukraine war. Chinese use of surveillance technology has continued apace in Xinjiang. As we stated last year, the extensive use of surveillance technologies has disturbing implications for human rights and poses a distinct threat to civil society.

·  Russian President Vladimir Putin has also shredded norms of behavior in space, publicly threatening to use an anti-satellite weapon against US Starlink satellites, arguing that they are not merely a commercial system but a military one as well. Ukraine has made use of Starlink in its conflict with Russia.

The Bulletin of the Atomic Scientists was founded in 1945 by Albert Einstein, J. Robert Oppenheimer, Eugene Rabinowitch and University of Chicago scientists who helped develop the first atomic weapons in the Manhattan Project. The scientists felt that they “could not remain aloof to the consequences of their work” and worked to inform the public and policymakers about man-made threats to human existence.

The Doomsday Clock was created in 1947 by the Bulletin of the Atomic Scientists to convey how close humanity is to destroying itself. Designed by painter Martyl Langsdorf, the Clock has become an international symbol of the world’s vulnerability to catastrophe from nuclear weapons, climate change and disruptive technologies.