Is There A Possibility Of A New Ice Age On Earth? | Naked Science | Spark

Spark28 minutes read

Earth experienced multiple snowball events, with evidence indicating freeze-overs over 2 billion years ago and significant changes post-thaw, enabling the evolution of complex life forms. Despite the sun warming over the last 650 million years, a future snowball Earth is possible if continents shift towards the equator, causing cooling temperatures and the potential formation of sea ice closer to the Equator.

Insights

  • The Snowball Earth theory posits that the planet experienced complete freezing multiple times in the past, potentially caused by extreme weathering and the lack of landmasses in higher latitudes allowing ice accumulation on the sea.
  • Evidence from dropstones in Australia and Soviet climate modeler M. Budyko's work suggest that runaway ice albedo feedback could lead to a catastrophic ice-covered state on Earth, emphasizing the potential for rapid global cooling and societal collapse in the event of a modern-day snowball Earth occurrence.

Get key ideas from YouTube videos. It’s free

Recent questions

  • What caused the Earth to freeze over 650 million years ago?

    Extreme weathering near the equator led to global glaciation.

Related videos

Summary

00:00

"Snowball Earth: Glaciers, Dropstones, and Catastrophe"

  • Earth was frozen solid 650 million years ago, with glaciers moving across the planet.
  • Snowball Earth theory suggests Earth froze over completely three times in the past.
  • If a snowball Earth event occurred today, it would lead to societal collapse and mass die-offs.
  • Dropstones found in Australia's Flinders Ranges indicate the presence of glaciers in the region.
  • The dropstones' magnetic orientation suggests Australia was near the equator when they formed.
  • Weathering, a process that consumes carbon dioxide, could have led to the Earth freezing over completely.
  • Extreme weathering due to continents' positions near the equator may have caused global glaciation.
  • The lack of landmasses in higher latitudes during the snowball Earth period allowed ice to accumulate on the sea.
  • Early life forms like cyanobacteria played a role in locking away carbon dioxide, cooling the Earth.
  • Ice albedo feedback, where ice reflects more sunlight, could have accelerated the cooling cycle during the snowball Earth event.

21:47

"From Frozen Seas to Snowball Earth"

  • Sea water frozen at 5 degrees above zero Fahrenheit in a cold room resembles modern-day sea ice, appearing gray and dull.
  • Another bucket contains salt water frozen at about 10 degrees below zero Fahrenheit, representing sea ice on Snowball Earth, turning its surface from gray to bright white due to crystal formation.
  • Salt molecules in ice at -10 degrees Fahrenheit form tiny gemstone-like crystals, altering the ice's appearance dramatically.
  • Soviet climate modeler M. Budyko demonstrated how runaway ice albedo could lead to a frozen Earth, akin to a nuclear winter's effects.
  • Budyko's work highlighted the potential for Earth to enter a catastrophic ice-covered state within a few decades due to rising ice albedo.
  • Evidence suggests Earth experienced multiple snowball events, with glacial deposits in South Africa indicating a freeze over 2 billion years ago.
  • The Great Oxidation Event, triggered by photosynthesizing microbes, led to plummeting greenhouse gases, causing the first snowball Earth.
  • A massive injection of greenhouse gases, like carbon dioxide, melted the snowball Earth, with subaerial volcanoes releasing CO2 even under ice.
  • The thaw of snowball Earth was marked by a drastic temperature increase, evidenced by carbonate rocks forming on glacial deposits globally.
  • The rise of oxygen post-snowball Earth enabled the evolution of complex multicellular life, coinciding with the appearance of the first animal fossils.

42:09

Sun's warming trend may prevent global freeze.

  • The sun has become 6% warmer over the last 650 million years due to nuclear fusion, making another deep freeze unlikely in the short term. However, a potential global freeze could occur if continents were to shift towards the equator, causing cooling temperatures and the formation of sea ice closer to the Equator, possibly leading to another snowball Earth millions of years in the future.
Channel avatarChannel avatarChannel avatarChannel avatarChannel avatar

Try it yourself — It’s free.