Nature in a experiment.

Why is it like so far?

Like it sounds so simple.

They had no idea.

But now the data's...

I find this not only refreshing, but at some level astounding.

Nature. Nature.

Welcome back to the nature podcast.

This week, capturing contrails at 30,000 feet... And what we can learn from fakery in science.

I'm Charmany Bandelle.

And I'm Benjamin Thompson.

Thank you. I'm Chamonie Bundell and I'm Benjamin Thompson. If it's a sunny day and you look up into the sky, it's pretty likely you'll see an aeroplane overhead.

And if this plane is flying as a high enough altitude,

you might see a long white plume behind it. These plumes are known as contrails, and they're made up of ice crystals. They're formed when water in the atmosphere condenses and freezes

around soot particles produced by a plane's engine.

And contrails can have a significant climate impact. The ice crystals can spread out to form

contral clouds. Now, these might only last a few hours, but they can trap heat, preventing it

from escaping Earth. Estimates suggest that the climate

effects of contrails almost equal those of the carbon dioxide emissions produced by the aviation

industry. As part of efforts to lower CO2 emissions, an increasing number of planes are being fitted

with what are known as lean burn engines. These are more fuel-efficient than

existing rich burn engines, but their effects on contrail formation wasn't well understood. That

...