To better grasp nuclear winter, scientists study wildfire cloud

A giant cloud from 2017 Canadian fires lingered in the atmosphere for a year, showing scientists how a cloud from a nuclear bomb would behave.

If a nuclear war were ever to occur, the toll would be catastrophic. Bombs would flatten entire cities, spreading deadly radiation far and wide. Fires sparked by the explosions would raze vast swaths of forest, sending toxic smoke streaming into the upper atmosphere where it would block the sun and trigger a global nuclear winter.

At least, that’s what the models say. Observations published Thursday in Science are confirming a key bit of physics underpinning those apocalyptic forecasts. The new data doesn’t come from a nuclear attack, but from a giant thundercloud formed by fire.

“Our previous model simulations showed that smoke, put into the lower stratosphere—above the layer where we live—would be heated and lofted to the upper

Unlock this story for free
Create an account to read the full story and get unlimited access to hundreds of Nat Geo articles.

Unlock this story for free

Want the full story? Sign up to keep reading and unlock hundreds of Nat Geo articles for free.
Already have an account?
SIGN IN

Read This Next

Why are these orcas killing sharks and removing their livers?
How to eat in 6 of the world’s most stunning places
Cliff art reveals the majesty of the Amazon’s aquatic realm

Go Further

Subscriber Exclusive Content

Why are people so dang obsessed with Mars?

How viruses shape our world

The era of greyhound racing in the U.S. is coming to an end

See how people have imagined life on Mars through history

See how NASA’s new Mars rover will explore the red planet

Why are people so dang obsessed with Mars?

How viruses shape our world

The era of greyhound racing in the U.S. is coming to an end

See how people have imagined life on Mars through history

See how NASA’s new Mars rover will explore the red planet

Why are people so dang obsessed with Mars?

How viruses shape our world

The era of greyhound racing in the U.S. is coming to an end

See how people have imagined life on Mars through history

See how NASA’s new Mars rover will explore the red planet