字幕表 動画を再生する 英語字幕をプリント With devastating hurricanes, refugee crisis and the real possibility of nuclear war. It can sometimes feel like the end is near. But what are the biggest threats to humanity and is there anything we can do to stop them? Experts all over the world from the Global Challenges Foundation in Stockholm and the Centre for the Study of Existential Risk at the University of Cambridge consider this question yearly using scientific research. Some risks lay millions of years into the future like gamma-ray burst caused by a star explosion which would destroy our ozone layer or even the over expansion or collapse of the entire universe. Closer to home we have our sun which will eventually become a red giant as it ages and engulf the entire planet but even that isn't for another 5 billion years. More imminent is an asteroid large enough to create a global catastrophe which is estimated to occur every 120,000 years. While none are currently expected to hit earth soon existing data is incomplete with a worldwide effort underway to to search the skies. Should it happen it could create a global cooling event like the ice age. But even smaller asteroids could have a significant impact on both natural and human ecosystems too. An even closer possibility is the super volcano the devastation in Pompeii from Mount Vesuvius released around 4 km cubic of magma but the super volcanos can release more than 500 km cubic. The real worry from this worldwide is the ash cloud which would block out the sunlight, cooling the globe and crippling agriculture. The last known eruption occurred around 25.000 years ago in New Zealand and researchers predict they occur every 30.000 to 50.000 years. Scientists are currently monitoring Yellowstone in the US as a future potential site. But not all of our threats are natural. Overpopulation can outstrip Earth's capacity to produce food and other resources. And amplify the threat of infectious pandemics due to high densities. Perhaps with bioengineered diseases. Conversely evidence is already pointing to declining fertility rates. Will we see the human population gradually die off from lack of births? Or will climate change beat this concern? A rise of 3 degrees Celsius would be incredibly significant with most of Florida and Bangladesh underwater. While several coastal cities would become swamped. On top of this longer and more damaging wild fire seasons, more destructive hurricanes, heat waves, food insecurity and drought. All of which can impact and amplify incidents of violence with. Nations already suffering from water and climate conditions which ultimately impacted deteriorating economic conditions. Then, there is nuclear war. Tensions over North Korea have brought this conflict to the forefront. With over 7000 known warheads between Russia and the US. And nukes within the UK, France China, India, Pakistan, Israel and North Korea. The doomsday clock created by the Bulletin of Atomic Scientists represents the likeliness of a man-made global catastrophe. Though the clock more recently included climate change and some other developments that put humanity at risk emphasis is placed on nuclear war. Since its creation in 1947, the furthest we've been from midnight or doomsday is in 1991 when the clock was 17 minutes to midnight. Today in 2017 the clock sits at 2.5 minutes to midnight. The second closest it has ever been. Even a small nuclear war could create a nuclear winter which would cause global cooling and damage to the ozone layer that may ultimately create droughts that lasts more than a decade. But the greatest threat of all: Researches currently believe it's artificial intelligence. If growth continues to become comparable to the industrial and agricultural revolutions Experts predict autonomous machines will attain near human level intelligence by 2075. And even if these machines don't become malevolent or evil what happens if those programmed to kill fall into the wrong hands? Or when AI programmed to do something good go about it with a destructive method? Thank you all so much for watching this video! If you liked it make sure that you subscribe so that you can see our videos that come out every Thursday. And we're gonna like some other videos over there that are similar to this one. About how rich people are prepping for the apocalypse and how to survive a nuclear war. This year is almost over. Hang in there! Peace guys!