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  • A group of scientists is saying that the asteroid impact that killed off the dinosaurs might've

  • changed the world far more than we realized!

  • Some 66 million years ago, a 10-kilometer-wide asteroid hit the Yucatan Peninsula and the

  • global effects killed more than three-quarters of all species, including dinosaurs and many

  • ocean-dwelling life forms.

  • The immediate aftermath was earthquakes, tsunamis, and volcanic eruptions, as well as vaporized

  • rock launched high above the surface that heated as it fell back to Earth, sparking

  • fires.

  • And these fires are what changed the climate and decimated most living things!

  • According to this new model: Soot from the global wildfires was heated by the Sun and

  • lofted high into the atmosphere.

  • There, it created an impenetrable barrier around the globe.

  • Just picture it

  • The planet is as dark as a moonlit night in the middle of the day, meaning little to no

  • photosynthesis.

  • Any plants not killed by wildfires are dead.

  • The the lynchpin of the ocean food chain -- phytoplankton -- is gone.

  • All the species that rely on these for food are dead.

  • The atmospheric soot causes global surface temperatures to drop by as much as 28 Celsius

  • over land and 11 over the oceans.

  • But the soot in the atmosphere keeps absorbing sunlight, heating the stratosphere, sucking

  • up water vapour, and destroying the ozone.

  • Eventually the atmosphere is cleared of soot, but only after a year of darkness, and then

  • the environment is decimated.

  • This is not a planet to call home.

  • Amazingly, this model shows it doesn't take a lot of soot for this kind of global devastation

  • to happen.

  • One simulation used just 5 billion tons of soot, about a third of what scientists think

  • was actually produced after the impact.

  • But this simulation isn't exact to how the world was 66 million years ago.

  • Still, it's a sobering thought.

  • While nuclear warfare or a smaller impact wouldn't have the same effects, either would

  • still put enough soot into the atmosphere to cool the surface and heat the upper atmosphere,

  • potentially changing the global climate enough to wipe out multiple species.

  • Speaking of wiping out species like dinosaurs, what colour were dinosaurs really?

  • We dug into it in this episode right here.

  • Let us know what other interesting science questions you'd like us to answer in the

  • comments, be sure to like this video, and subscribe for more Seeker.

A group of scientists is saying that the asteroid impact that killed off the dinosaurs might've

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An Alternative Theory About What Could Have Killed The Dinosaurs

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    joey joey に公開 2021 年 04 月 17 日
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