© 2026 Connecticut Public

FCC Public Inspection Files:
WEDH · WEDN · WEDW · WEDY
WEDW-FM · WNPR · WPKT · WRLI-FM
Public Files Contact · ATSC 3.0 FAQ
Play Live Radio
Next Up:
0:00
0:00
0:00 0:00
Available On Air Stations

How Volcanoes Froze the Earth...Twice

Season 2 Episode 29 | 10m 29s

Over 600 million years ago, sheets of ice coated our planet on both land and sea. How did this happen? And most importantly for us, why did the planet eventually thaw again? The evidence for Snowball Earth is written on every continent today.

Aired: 08/10/19
Extras
Get ready for the all-new season, coming January 17, 2027 at 9/8c.
Get a sneak peek at a brand new season of NATURE on PBS.
New discoveries reveal how pivotal Great Zimbabwe was to global trade.
Discover all-new Secrets of the Dead on Wednesdays this fall, starting October 14 at 10/9c.
Join Elmo and the Sesame Street gang on a once-in-a-lifetime African safari adventure.
Discover filmmaker and playwright Luis Valdez, a founding figure of the Chicano Movement.
A filmmaker explores racial justice in his hometown as he returns to his conservative father.
On Antarctica’s barren nunatuks, Dr. Ry Holland searches for microbial life.
Austrian scientist Dr. Birgit Sattler studies the microbial life that exists in ice.
Appraisal: WPA Puppets
Latest Episodes
All
  • All
  • Eons Season 9
  • Eons Season 8
  • Eons Season 7
  • Eons Season 6
  • Eons Season 5
  • Eons Season 4
  • Eons Season 3
  • Eons Season 2
  • Eons Season 1
Life begins to rebound after the destruction of the mass extinction ending the Permian Period.
An apocalypse ended the Permian Period 252 million years ago, wiping out more than 80% of species.
The first saber-teeth and tusks evolve in the Late Permian and our ancestors, the cynodonts, appear.
An extinction in the Middle Permian decimates life, from a fossil reef to our ancient relatives.
The first herbivorous vertebrates evolve on the side of the amniote family tree leading to mammals.
Seed plants and amniotes adapt to dry climates, helping them thrive on Pangea in the Permian Period.
How did Homotherium evolve to be so successful? The answer may lie in the rise of the Tibetan plate.
The mystery of what non-flying dinosaurs were doing with their feathered wings has a new hypothesis.
What did ancient people once know about these bizarre megafauna that we’ve since forgotten?
5,700 years ago, woolly mammoths crossed a remote tundra island off Alaska.