Nuclear Notebook: How many nuclear weapons does Russia have? Russia is in the second half of a decades-long modernization of its strategic and non-strategic nuclear forces to replace Soviet-era weapons with newer systems. These modernizations, combined with an increase in the number and size of military exercises and occasional explicit nuclear threats against other countries, … Continued

The May/June 2018 Issue: The wages of climate inaction: Ever-rising seas The science behind sea-level rise has long been understood, and a recent study has found that by the year 2300, sea levels will be 8 inches higher for every 5 years that carbon dioxide levels keep rising. Exactly what happens, and when, will be … Continued

Explore our deep dive into sea-level rise. What does “average global sea-level rise” mean, and what are the global and regional consequences when all the ice melts on the far-away West Antarctic Ice Sheet?

In early February, the Trump administration unveiled a $1.5-trillion infrastructure plan that has received criticism on several fronts. Chief among the complaints is a lack of planning for civil and infrastructure disruptions resulting from extreme weather and a changing climate. But the Trump administration isn’t unique in this regard: studies indicate that governments around the world underinvest in infrastructure resilience by at least 70 percent. But what do we mean when we say “resilience?” And who benefits from efforts that do exist?

Nuclear Notebook: How many nuclear warheads does the United States have? At the beginning of 2018, the US Defense Department maintained an estimated stockpile of 4,000 nuclear warheads for delivery by more than 800 ballistic missiles and aircraft. Since September 2009, when the United States announced that the nuclear arsenal contained 5,113 warheads, the stockpile … Continued

On February 2, the Pentagon rolled out the unclassified version of the Trump administration’s Nuclear Posture Review. The 2018 document contains significant changes over the last NPR, which was completed in 2010. The Bulletin will be publishing analyses of the NPR document itself and how it might be implemented.

Because it is the keeper of the Doomsday Clock, the Bulletin of the Atomic Scientists is occasionally (if quite wrongly) accused of fear-mongering. The magazine, its editors, and its authors could more accurately be charged with hope-mongering. 

Nuclear Notebook: How many nuclear weapons does North Korea have? North Korea has made significant advances over the past two decades in developing a nuclear weapons arsenal. It has detonated six nuclear devices – one with a yield of a couple hundred kilotons – and test-flown a variety of new ballistic missiles that potentially put … Continued

In this issue, four top experts assess the Trump administration’s performance in regard to the major, continuing global threats at the heart of the Bulletin’s mission: nuclear weapons, climate change, man-made biological agents, and cyber attacks on democracy.

Nuclear Notebook: How many nuclear weapons does the U.S. have in South Korea? During the Cold War, the United States deployed nuclear weapons in South Korea continuously for 33 years, from 1958 to 1991. The South Korean-based nuclear arsenal peaked at an all-time high of approximately 950 warheads in 1967. Since the last US nuclear … Continued

  Regardless of who occupies the White House, the most difficult challenges that the United States and other governments around the world face are dealt with over time spans counted in years, and often decades. Yet, each year of a US presidency contributes to crucial global action that cannot be squandered or reversed if nations … Continued

The current sense of “hybrid war,” was introduced in 2005, when James N. Mattis, now the US defense secretary, and National Defense University researcher Frank Hoffman called it “a combination of novel approaches—a merger of different modes and means of war.” Since then, the use of hybrid warfare techniques has expanded dramatically, from Iran’s blend … Continued

Nuclear Notebook: How many nuclear weapons are there in the world? As of mid-2017, we estimate that there are nearly 15,000 nuclear weapons located at some 107 sites in 14 countries. Roughly, 9400 of these weapons are in military arsenals; the remaining weapons are retired and awaiting dismantlement. Approximately 4150 are operationally available, and some … Continued

As the security situation ratcheted up on the Korean Peninsula over the last week, the  Bulletin’s staff, leadership, and columnists quickly jumped into action, providing a trusted source of information to help track and make sense of unfolding events. Here is a summary of what we’ve been up to, in case you missed it: Los … Continued

It’s been 72 years since the Bomb was dropped on Hiroshima and, a few days later, on Nagasaki, Japan. Since that week in August when the world was changed forever, the global nuclear arsenal has risen and dropped. Countries have joined and left the nuclear weapons club, with North Korea becoming the most recent member. … Continued

Check out our latest interactive, “Know the Time,” an animation of technological advancement and global risk, documented by the Doomsday Clock. It was created by Fabian Stricker, Mapper and Digital Business Integration Analyst, who became concerned about global risk due to the alarming rhetoric used during the 2016 US presidential election. Follow Fabian on Twitter … Continued

To the founders of the Bulletin of the Atomic Scientists in 1945, the idea of a global ban on nuclear weapons would have been cause for celebration. So what should we make of the treaty that was adopted at the United Nations on Friday? Here’s what you need to know: On the prohibition of nuclear … Continued

Over the decades since the Hiroshima and Nagasaki bombings, the worldwide taboo against the use of nuclear weapons drove agreements such as SALT, START and the INF Treaty. Over the last year, however, the taboo seems to be weakening: North Korea continues to test nuclear weapons, Russia is apparently re-thinking its commitment to the INF … Continued

Nuclear Notebook: How many nuclear weapons does India have? India continues to modernize its nuclear arsenal with development of several new nuclear weapon systems. We estimate India currently operates seven nuclear-capable systems: two aircraft, four land-based ballistic missiles, and one sea-based ballistic missile. At least four more systems are in development. The development program is … Continued

Nuclear Notebook: How many nuclear weapons does Russia have? Russia is in the middle of a broad modernization of its strategic and nonstrategic nuclear forces. While much of this process is simply a continuation of well-known programs that have been underway for many years, some developments are new. These modernizations, combined with an increase in … Continued