On July 16, 1945, in the desert near Alamogordo, New Mexico, the United States conducted the first-ever atomic explosion. This marked a turning point in world history. Just three weeks later, nuclear bombs were dropped on the Japanese cities of Hiroshima and Nagasaki. 

Since then, more than 2,000 nuclear tests have been conducted – on land, underwater, and underground. The development and testing of nuclear weapons have had far-reaching political, humanitarian, and environmental consequences. 

                                            The Trinity bomb explosion

In the aftermath of the Second World War and the nuclear bombs over Hiroshima and Nagasaki, the international community mobilised to curb nuclear weapons development. Landmark agreements followed, including the Treaty on the Non-Proliferation of Nuclear-Weapons (NPT), which entered into force in 1970, and the Comprehensive Nuclear-Test-Ban Treaty (CTBT), adopted in 1996. 

The CTBT prohibits all forms of testing of nuclear weapons. To date, 178 countries have signed and ratified the treaty, while nine others have signed but not yet ratified it. Despite not having formally entered into force, the CTBT has had a strong normative impact. Since 2000, only a few tests have been conducted, with North Korea being the only state to carry out nuclear tests in recent years. 

As a result of the treaty, the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) was established. It operates one of the most advanced global monitoring systems in existence, with more than 300 stations capable of detecting nuclear test explosions anywhere in the world.  

Eighty years after the Trinity test, nuclear weapons still pose a serious challenge to global security. Although the number of tests has decreased significantly, the work of non-proliferation, disarmament, and verification remains as critical as ever. Maintaining and strengthening the global verification system is a cornerstone of international efforts to nuclear non-proliferation.  

NORSAR, which represent Norway’s national data centre and technical expertise in the CTBTO, operates key seismic monitoring stations and contributes world-leading expertise in nuclear test detection. At NORSAR, we are proud to operate several facilities of the International Monitoring System, doing our part to prevent that nuclear testing nor the use of nuclear weapons ever happens again. Our work is a vital contribution to global peace and security.