Scientists from the Bulletin of the Atomic Scientists moved the publication's "Doomsday Clock" forward by 30 seconds on Thursday, the closest the symbolic measure has been to midnight since the height of the Cold War.

The clock, which now stands at two minutes to twelve — the closest to midnight since 1953 — is a widely cited estimation for how likely the world is to a global catastrophe.

"In 2017, world leaders failed to respond effectively to the looming threats of nuclear war and climate change, making the world security situation more dangerous than it was a year ago—and as dangerous as it has been since World War II," the Bulletin said in its annual report explaining the change.

The Bulletin — led by a group of intellectuals that includes 15 Nobel laureates — has made the estimation every year since creating the clock in 1947. The dial moved to 2 minutes and 30 seconds to midnight in 2017 following the election of US President Donald Trump.

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Nuclear risk

An increased risk of nuclear weapons being used in 2017 was the main reason for Thursday's decision.

The Bulletin cited growing tensions about North Korea's weapons program, arms control disputes between Russia and the US and the continuing nuclear arms race between Pakistan and India.

On the Korean Peninsula, the public spat between North Korean leader Kim Jong Un and US President Donald Trump had made tensions worse, it said.

"Hyperbolic rhetoric and provocative actions by both sides have increased the possibility of nuclear war by accident or miscalculation."

Read more: Pope Francis bemoans 2017 as a year of war, lies and injustice

ICBM threat and North Korea's overall military strength Major achievement In early June 2017, North Korea test-launched an intercontinental ballistic missile (ICBM) for the first time. Testing an ICBM marked a major military achievement for Pyongyang and a serious escalation of tensions with the United States and its allies in the region, particularly South Korea and Japan.

ICBM threat and North Korea's overall military strength Trouble with warheads At the time, defense experts said the ICBM could reach as far as the US states of Alaska and Hawaii. However, it was unclear if North Korea can field an ICBM capable of carrying a nuclear warhead on its cone that could survive reentry into the Earth's atmosphere. North Korean state media claimed the ICBM was capable of carrying a "large, heavy nuclear warhead" to any part of the United States.

ICBM threat and North Korea's overall military strength Pyongyang's nuclear tests - six times and counting The ICBM is believed to be a step forward in the North's nuclear program. Despite pressure from the international community, Pyongyang has made no secret of its nuclear ambitions. Alongside its ritual ballistic missile tests, North Korea has conducted nuclear tests on at least six occasions, including one in September 2017.

ICBM threat and North Korea's overall military strength US running out of patience? Responding to the first ICBM test with a show of force, the US and South Korean troops on conducted "deep strike" precision missile drills using Army Tactical Missile System (ATACMS) and the Republic of Korea's Hyunmoo Missile II. In April, the US sent its Carl Vinson aircraft carrier towards the Korean Peninsula, saying it was taking prudent measures against the North.

ICBM threat and North Korea's overall military strength Testing the boundaries Ignoring international condemnation, Pyongyang test-launched another rocket on July 28, 2017, just weeks after its first ICBM test. In both of the tests, North Korea used Hwasong-14 missile, but the second one reached a higher altitude and traveled a larger distance than the first one, according to the state media.

ICBM threat and North Korea's overall military strength Whole of US within range? Pyongyang conducted its third test November 29, using a newly developed Hwasong-15 missile. US, Japanese and South Korean officials said it rose to about 4,500 km (2,800 miles) and flew 960 kilometers (600 miles) over about 50 minutes before landing in Japan's exclusive economic zone off the country's coast.

ICBM threat and North Korea's overall military strength One of the world's largest militaries Apart from a developing missile and nuclear program, North Korea has a powerful army with 700,000 active troops and another 4.5 million in the reserves. It can call upon almost a quarter of its population to serve in the army at any given time. The North's bloated army is believed to outnumber its southern neighbor's by two-to-one.

ICBM threat and North Korea's overall military strength Vast capabilities According to the 2017 Global Firepower Index, the North has, as part of a far-reaching arsenal, 458 fighter aircraft, 5,025 combat tanks, 76 submarines, and 5,200,000 total military personnel. The picture above from 2013 shows leader Kim Jong Un ordering strategic rocket forces to be on standby to strike US and South Korean targets at any time.

ICBM threat and North Korea's overall military strength Enemies all around Alongside the United States, Pyongyang views its neighbors South Korea and Japan as its two other main enemies. North Korea has used US military exercises in the region as means of galvanizing its people, claiming that the exercises are dress rehearsals for an impending invasion.

ICBM threat and North Korea's overall military strength Huge, colorful demonstrations of military might Every year, hundreds of thousands of soldiers and citizens roll through the streets of the capital Pyongyang to take part in the North's military parades. Preparations for the rallies often begin months in advance, and the parades usually mark important anniversaries linked with the Communist Party or Kim Jong Un's family.



Climate dangers, technological abuse

The Bulletin also said a lack of progress on combating global warming and the "abuse" of new technologies had also motivated their decision.

"After plateauing for a few years, greenhouse gas emissions resumed their stubborn rise in 2017," it said. "The existential threat posed by climate change looms larger."

Meanwhile, sophisticated new technologies have allowed hackers to undermine political stability in many democratic countries. The report also cited the prospect of fully autonomous weapons.

Read more: Global warming: 2017 was second-warmest, last three years are record hot

Hope?

The Bulletin said the world could become "safer and saner" if leaders reduced global tensions, stopped expanding nuclear weapon arsenals, reined in carbon emissions and took steps to control new technologies.

"The Doomsday Clock has ticked away from midnight in the past, and during the next year, the world can again move it further from apocalypse."