Winter is Coming
Nuclear winter is a hypothetical phenomenon that is somewhat like a volcanic winter. During the most epic of eruptions, plenty of aerosols and fine particulate matter is produced. They are incredibly reflective, and if they manage to get into the upper atmosphere, the net result is that they cool the planet.
Historically, humans have witnessed volcanic cooling for several years at a time. Before we existed, there were several mass extinction events driven partly by volcanic effusions that – while also warming it with a huge expulsion of carbon dioxide – cooled the world for many hundreds of years at a time, perhaps longer.
A nuclear winter is essentially the same, except that the world will only cool and the particulate, ash-like matter will be radioactive. Breathe enough of this in and you’ll quickly die. So how many nuclear fireballs are needed to initiate a powerful enough nuclear winter?
One study suggests that 100 Hiroshima-style blasts will produce enough black carbon soot to cause a “small” nuclear winter. This would reduce the global average temperature by roughly 1°C (1.8°F), offsetting the recent bout of man-made global warming – problem solved, then?
If every single one of the world's nukes went off, then, there will be a near-100 percent reduction in solar radiation reaching Earth’s surface for several years, meaning the planet would be shrouded in perpetual darkness for that time. Light would creep in increasingly, but slowly over the next few decades or even centuries.
Video games have often looked into possible post-apocalyptic futures. Bethesda Softworks via YouTube
Suffice to say, this would all but stop photosynthesis. Only the hardiest of plants would not die out, which would lead to a collapse in the global food chains. There would be a mass extinction event – including perhaps our own species – and the survivors would have to fend for themselves in an irradiated landscape.
So yeah, not great. Let’s hope President Trump doesn’t treat the nuclear button as impulsively as he fires off tweets.