Nuclear Notebook

Since 1987, the Bulletin of the Atomic Scientists has published the Nuclear Notebook, an authoritative accounting of world nuclear arsenals compiled by top experts from the Federation of American Scientists. Today, it is prepared by Hans M. Kristensen and Robert S. Norris of FAS. The Nuclear Notebook is housed at Taylor & Francis Online, home of our digital journal. Because of its importance to researchers, governments, and citizens around the world, the Nuclear Notebook is always free-to-access. Click on the individual links below to read the corresponding link at tandfonline.

2 November 2017
Nuclear notebook

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.

3 September 2017
Nuclear notebook

The authors estimate that as of mid-2017, there are nearly 15,000 nuclear weapons in the world, 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.

4 July 2017
Asia
Nuclear notebook

India continues to modernize its nuclear arsenal, with at least four new weapon systems now under development to complement or replace existing nuclear-capable aircraft, land-based delivery systems, and sea-based systems.

4 March 2017
Nuclear notebook

Russia is in the middle of a broad modernization of its strategic and nonstrategic nuclear forces, including both new programs and some that have been underway for many years.

2 January 2017
Nuclear notebook

The US nuclear arsenal remained roughly unchanged in the last year, with the Defense Department maintaining an estimated stockpile of some 4,480 warheads to be delivered via ballistic missiles and aircraft.

1 November 2016
Nuclear notebook

Pakistan has a nuclear weapons stockpile of 130–140 warheads and appears to have plans to increase its arsenal further.

3 July 2016
Nuclear notebook

The modernization of China’s land-based nuclear-capable missile force has progressed significantly over the past year, with Beijing fielding a new version of an existing nuclear missile and a new dual-capable missile. The country has also reorganized its nuclear missile command structure.

3 May 2016
Nuclear notebook

Russia is in the middle of a broad modernization of its strategic and nonstrategic nuclear forces, including some new developments.

3 March 2016
Nuclear notebook

The US nuclear arsenal remained roughly unchanged in the last year, with the Defense Department maintaining an estimated stockpile of some 4,670 warheads to be delivered via ballistic missiles and aircraft. Most of these warheads are not deployed but stored, and many are destined to be retired.

2 January 2016
Nuclear notebook

Newly declassified documents from the US Defense Department show how many nuclear weapons the United States deployed at sea between 1953 and 1991.

1 November 2015
Nuclear notebook

Pakistan has a nuclear weapons stockpile of 110 to 130 warheads, an increase from an estimated 90 to 110 warheads in 2011.

1 September 2015
Nuclear notebook

With several long-range ballistic missiles in development, the Indian nuclear posture is entering an important new phase. After nearly two decades of focusing on nuclear competition with Pakistan, New Delhi seems to now be paying attention to its future strategic relationship with China.

1 July 2015
Asia
Nuclear notebook

China is the only one of the five original nuclear weapon states that is quantitatively increasing the size of its nuclear arsenal and it now is estimated to have approximately 260 warheads. The arsenal’s capabilities are also increasing as older missiles are replaced with newer ones.

1 May 2015
Nuclear notebook

Russia is modernizing its strategic and nonstrategic nuclear warheads. It currently has 4,500 nuclear warheads, of which roughly 1,780 strategic warheads are deployed on missiles and at bomber bases. Another 700 strategic warheads are in storage along with roughly 2,000 nonstrategic warheads.

1 March 2015
Americas
Nuclear notebook

As of early 2015, the authors estimate that the US Defense Department maintains about 4,760 nuclear warheads. Of this number, they estimate that approximately 2,080 warheads are deployed while 2,680 warheads are in storage.

1 January 2015
Nuclear notebook

Over 28 years of weapons analysis, the Nuclear Notebook column has revealed surprise nuclear activity and spot-on arsenal estimates while becoming a daily resource for scholars, activists, and journalists.

1 November 2014
Middle East
Nuclear notebook

Although the Israeli government neither confirms nor denies that it possesses nuclear weapons, it is generally accepted by friend and foe alike that Israel is a nuclear-armed state—and has been so for nearly half a century.

1 September 2014
Nuclear notebook

As of mid-2014, the authors estimate that there are approximately 16,300 nuclear weapons located at some 98 sites in 14 countries. Roughly 10,000 of these weapons are in military arsenals; the remaining weapons are retired and awaiting dismantlement.

1 July 2014
Nuclear notebook

The nuclear-armed states have large residual nuclear arsenals, and post-Cold War reductions of nuclear weapons have slowed. Meanwhile, the nuclear nations have undertaken ambitious nuclear weapon modernization programs that threaten to prolong the nuclear era indefinitely.

1 May 2014
Nuclear notebook

The Obama administration has approved an upgrade to the B61 nuclear bomb that will, through use of a new tail kit assembly, become a guided standoff nuclear bomb.

1 March 2014
Asia
Nuclear notebook

Russia has taken important steps in modernizing its nuclear forces since early 2013, including the continued development and deployment of new intercontinental ballistic missiles (ICBMs), construction of ballistic missile submarines, and development of a new strategic bomber.

1 January 2014
Nuclear notebook

The United States has an estimated 4,650 nuclear warheads available for delivery by more than 800 ballistic missiles and aircraft. Approximately 2,700 retired but still intact warheads await dismantlement, for a total inventory of roughly 7,400 warheads.

1 November 2013
Nuclear notebook

The number of weapons in China’s nuclear arsenal is slowly growing, and the capability of those weapons is also increasing.

16 October 2013
Nuclear notebook

The authors calculate that some 125,000 nuclear warheads have been built since 1945, about 97 percent of them by the United States and the Soviet Union and Russia.

1 July 2013
Europe/Russia
Nuclear notebook

Recent research has revealed new facts about the British nuclear arsenal over a 25-year period starting in 1953. This accounting and the authors’ own research support an estimate that the British produced about 1,250 nuclear warheads between 1953 and 2013.

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