This is the closest the clock has been to disaster since early above-ground hydrogen bomb testing, according to the Bulletin's press release. A team of scientists adjust the Doomsday clock annually based on conditions of positive and negative variation in climate change, nuclear weapons, biotechnology and other technological advancements.
One of the Bulletin members said during the live announcement that the deteriorating relationship between the United States and Russia has sparked concern among the scientists that an arms control agreement is unlikely. "Russia is unlikely to negotiate on tactical nuclear weapons," she said, adding that "We have some deeply disturbing nuclear rhetoric from Russia."
On the issue of climate change, another member cited 2015 being the warmest year on record and 15 of the 16 warmest years having occurred since 2000 as evidence that "There's no question that marked climate change is underway." He considered the Paris climate agreement a "tentative success in the international efforts to deal with climate change" but a "very ambitious goal."
In January 2015, scientists downgraded the clock from five minutes to three minutes, citing that "Unchecked climate change, global nuclear weapons modernizations and outsized nuclear weapons arsenals pose extraordinary and undeniable threats to the continued existence of humanity, and world leaders have failed to act with the speed or on the scale required to protect citizens from potential catastrophe."