Placeholder Image

Subtitles section Play video

  • In December 2016, a remote community in Siberia experienced a mysterious outbreak.

  • 90 people were hospitalized, and a 12-year-old boy died.

  • Soon, Russian officials identified what had killed him.

  • The deadly infectious disease, anthrax.

  • The outbreak had started among reindeer.

  • To contain the spread, they burned over 2,000 reindeer carcasses.

  • The strange thing was, there hadn't been an anthrax outbreak in the area for more than 70 years.

  • So, to figure out where it came from, scientists started looking underground.

  • In the coldest parts of the world, there's a layer of the Earth that stays frozen all year.

  • Every summer, the soil above it thaws, but this deeper layer stays hard as rock.

  • This is permafrost.

  • Most permafrost is here, in the Northern Hemisphere around the Arctic.

  • And because it never thaws, permafrost acts kind of like the freezer in your kitchen.

  • When plants and animals here die, they don't actually decompose.

  • Instead, they become preserved in the frozen earth, like a time capsule.

  • And it's been that way for thousands of years.

  • But that's changing.

  • Today, humans are burning carbon and making the atmosphere warmer.

  • And that's causing the permafrost to thaw and shrink.

  • By 2100, only these areas will still have any permafrost.

  • And that's causing some problems.

  • When permafrost melts, the land above it becomes unstable, which can lead to landslides.

  • Man-made structures start to fall apart, as the ground underneath them collapses.

  • And dead plants and animals that had been frozen for years are starting to thaw out.

  • As they're exposed to air and bacteria, this organic material starts to decompose.

  • That releases greenhouse gases like carbon dioxide and methane.

  • But that's not all it releases.

  • In Siberia, scientists think that the anthrax outbreak came from a long-dead reindeer carcass that thawed out along with the permafrost.

  • Anthrax spores from the carcass would have spread across the area and infected reindeer grazing nearby.

  • And it's not just anthrax.

  • Scientists worry that, as permafrost melts, it could unearth all sorts of diseases we thought we had under control.

  • 35 million people live around permafrost.

  • But the carbon released, as permafrost melts, will accelerate the impacts of climate change everywhere.

  • Rising seas, heat waves, droughts in some places, and floods in others.

  • And now we can add one more thing to that list, diseases we thought we conquered.

In December 2016, a remote community in Siberia experienced a mysterious outbreak.

Subtitles and vocabulary

Click the word to look it up Click the word to find further inforamtion about it