Subtitles section Play video Print subtitles Approaching the shores of Sicily, you're enjoying the views. The wind brings pleasant coolness, and you anticipate your vacation. But suddenly, the boat shakes, and you lose balance. You look up and see a huge plume of black smoke rising above the Etna volcano... I'll switch from your perspective now because you won't like what happens to you in the next several minutes. Let's take a look at the planet from the space. All across its surface you see billowing spots of smoke - that's all the volcanoes on Earth starting to erupt at once. Smoke is kind of a herald of what's to come: it rises first, warning us of the danger. And then it varies for different volcanoes. The active ones, like Etna in Sicily, will start spitting fire and rocks. They haven't been slumbering to start with, so the magma at their core is hot and volatile. Smoking boulders will fire up from the crater and fall on the ground nearby, while a fountain of lava spews up and swiftly goes down the slopes. The temperature of this hot mess is anywhere from 1,300 to 2,200 degrees F, which is a bit too warm for comfort. Anything this stream touches will burst into flames at once, but not for long: lava is molten rock, and outside the Earth's hot core it will soon cool down and become solid. What is left afterwards is a greyish black mass that looks kinda wavy. Other volcanoes will have been sleeping for too long, and their stock of lava wasn't that huge to begin with, so they won't really make a blast. Rather, lava will slowly flow over the edge of the crater and pour down their slopes. With a bit of luck, everyone in the vicinity will be safe because the hot stream won't reach much further than the foothills - or shall I say, footvolcanoes? Others still - and they're actually a vast majority - are underwater, so their eruptions will be very different. When a submerged volcano erupts, no one on the surface will even notice it if they're just a bit away. The water right above the volcano will start bubbling, and its temperature will rise a lot. You'll probably also smell the stench of rotten eggs - that's methane and sulfur coming from down below. If you're unfortunate enough to be in that exact spot, though, you'll want it to be about a couple of hundred degrees cooler. There might also be a hefty amount of pumice floating around - that's lava that cooled down in the water and got filled with air bubbles. And then there are supervolcanoes. There are only four of them on the planet, the most famous being the Yellowstone supervolcano. If even one of these giants erupts, it will do so much damage it will change the landscape of large part of the continent it's on. Now, like I said, all volcanoes on Earth start erupting at once. It’s a bad day -- I’m guessing a Monday. Almost immediately they bring disaster to their surrounding areas with hot lava and rockfall. As soon as that stops, smoke rises into the atmosphere, and ash starts falling to the ground. It looks like snow, only black. But ash is heavy and clingy, so when it falls onto roofs of the buildings, it clumps together and soon makes them collapse under its weight. It's also very dangerous to inhale this ash because it blocks the airways, not letting you breathe. Quite soon ash covers everything. It blankets all surfaces, smothering grass, trees, and bushes, and they stop producing oxygen. Smoke, on the other hand, creates a full-blown veil in the skies above. This veil doesn't let the sunshine through, so the planet starts to cool down by degrees. It becomes colder and colder, until a new ice age begins. If there's still someone alive by this point, they'll have to deal with freezing cold and huge glaciers far beyond their typical area. Closer to the equator, though, it might be warmer than elsewhere, so there’ll still be hope. But the irony is that CO2 is a greenhouse gas, and after a while its high concentration in the atmosphere will warm up the planet again. The ice will draw back, and for some time Earth will have a good inhabitable climate, but not nearly long enough for life to thrive. Soon, the temperatures will rise to unbearable values, and it’ll be scalding hot until CO2 goes away at least in part. Only then the planet might begin to return to normal, but it may take thousands of years. Meanwhile, the oceans boil too. There are hundreds of underwater volcanoes, and they erupt as well, throwing out thousands of tons of gas and magma. And if magma stays mostly on the bottom of the sea, gases go up and make the water hot and acidic. Much of the marine life can’t adapt to the changing conditions this fast, and lots of species face mass extinction. Only the sturdiest remain, and those are microscopic creatures that somehow survive boiling temperatures at the crevices in the ocean’s bottom. In the next few hundred or even thousand years, life on Earth is virtually nonexistent. About 95% of all living things are gone — it’s basically the same as what happened when a meteorite struck the planet in the era of dinosaurs. Volcanoes have wiped out life, leaving only a veil of darkness in the sky, plains of ash and solid magma on land, and acid instead of water in the ocean. If you looked at the Earth from above, you would only hardly recognize the once blue and green planet. But then, after sufficient time has passed, Earth will begin recovering. At first, when carbon dioxide dissipates and the temperature returns to more or less normal, plants will start appearing. Solid magma and ash might make the land look desolate, but in fact they’re a rather good soil for the green. If you look at Kamchatka, for example, you’ll see there’s grass and flowers and bushes springing from the black mass around the less active volcanoes. So given enough time, the lands will become lush and booming with plant life — probably more than ever. With the return of grass and trees, oxygen will start pumping into the atmosphere. When it’s rich enough, the air will once again become breathable for creatures with lungs. But it will be a very long time before they appear once more. Since most life is gone, the cycle will have to begin anew, from the smallest critters you can’t even see with a naked eye. Thousands of years pass, and evolution kicks in. New and bigger species appear. They continue evolving and growing, different animal families pop up, and chances are very high they don’t resemble anything we’ve ever seen on our planet. They might have six legs instead of four, for all we know, or even two heads! Possibilities are endless. And finally, at some point in the distant future, there appears the first species that learns to use tools. For us, these were primates. For the Earth of the future, they could be anything. In any case, when they find sticks and stones and start sharpening them to make stakes and primitive axes, it will be the first step towards a new civilization. In a few more thousand years, a new intelligent species will begin building their homes on the planet we used to claim for our own. Let’s just hope they won’t have to deal with a massive all-out volcanic eruption same as our civilization did. Well, hypothetically, of course. Anyway, back to the now: what are the chances of having such a disaster? Next to none, in fact. Scientists point out there has never been an eruption of this kind on Earth, and there’s no indication it might happen in the future. You see, magma comes from the upper layer of the Earth’s mantle. As it is, mantle is solid, but it’s so hot that some part of it melts down, becoming fluid rock. When a volcano erupts, it means that the pressure of this molten layer has become too much, and it needs to get out on the surface. Once it does, the volcano it sprang from falls into slumber once more, only leaving traces of lava down its slopes and, hopefully, no calamities nearby. So, if all volcanoes on Earth were to erupt, it would take an extraordinary amount of excess magma in the mantle. And since there’s not so much of it in the first place, such a collective explosion is next to impossible. Ah, that’s a relief. Now, about that big asteroid approaching from over there…ha just kidding. Hey, if you learned something new today, then give the video a like and share it with a friend! And here are some other videos I think you'll enjoy. Just click to the left or right, and stay on the Bright Side of life!
B1 BRIGHTSIDE magma lava earth ash planet What If All Volcanoes on Earth Start Erupting at Once 8 0 林宜悉 posted on 2020/03/06 More Share Save Report Video vocabulary