Doomsday Clock Graph
A graph outlining the Doomsday Clock changes throughout its history. Wikimedia Commons

The Bulletin of the Atomic Scientists is keeping its longtime Doomsday Clock at five minutes to midnight for 2013, and the committee of scientists and Nobel Laureates is urging President Barack Obama to address the threat of global climate change.

The Bulletin of the Atomic Scientists was established in 1945 by several University of Chicago scientists who were involved in the Manhattan Project that developed the atom bomb that year. The Doomsday Clock was unveiled in 1947 to “convey threats to humanity and the planet.” The group's current lineup has 18 Nobel laureates.

The Doomsday Clock acts as a countdown to a possible apocalypse, symbolized by midnight. Each minute closer to midnight, the closer humanity is to catastrophe. For decades the Doomsday Clock was determined by nuclear threats, but of late the Bulletin of Atomic Scientists has factored in other threats, focusing on global climate change for 2013.

The closest the Doomsday Clock has ever been to midnight occurred in 1953 when it was two minutes, amid atmospheric testing of nuclear devices by the United States and the Soviet Union. In 2012, the Doomsday Clock was also set to five minutes and is staying there for 2013 for several reasons that the Bulletin of the Atomic Scientists outlined in an open letter to President Barack Obama.

The scientists express hope for Obama’s second term and note some progress, but point to three main causes for concern. “In the U.S. elections the focus was 'the economy, stupid,' with barely a word about the severe long-term trends that threaten the population's well-being to a far greater extent: climate change, the continuing menace of nuclear oblivion, and the vulnerabilities of the world's energy sources.”

The Bulletin cites the Fukushima Daiichi nuclear power station meltdown in Japan in 2011 as one reason why nuclear energy is still a concern. The letter applauds Obama’s efforts to contain nuclear proliferation but urges the United States to reduce its nuclear arsenal to less than 1,000 warheads.

The Bulletin also calls on Obama to renew his efforts to secure any "loose" material that could be used for nuclear weaponry, such as plutonium or enriched uranium. According to a report, there is more than 500 tons of separated plutonium at large, enough to make thousands of nuclear warheads.

Aside from nuclear weaponry, climate change poses the greatest risk to humanity. In the letter, the scientists say, “emissions of heat-trapping gases continued to climb in 2012, with atmospheric levels of carbon dioxide -- the most important greenhouse gas affected by human activities -- reaching levels higher than at any time in the past 800,000 years.” The letter also cites 2012 being the hottest year in recorded history as well as record low Artic Ocean sea ice levels as more evidence of the urgency of facing global climate change.

The letter urges the president to work toward curbing greenhouse emissions by working with other world leaders as well as increasing incentives to fund alternative fuel sources. The letter also addresses the possible emerging threat of cyber attacks which could cripple a nation’s or corporation’s infrastructure.

The letter closes with a sense of optimism stating, “You have an extraordinary capacity to articulate the global desire for peace and security, and you have the tools to deliver tangible progress. Your Prague speech on nuclear disarmament and your efforts at Copenhagen to coordinate world leaders to slow the onset of climate change are high water marks in their respective basins of activity.”