Adam Kucharski

One of the most popular conspiracy theories currently is the idea of chemtrails.

This is the false claim that aeroplane vapor trails are actually a deliberate attempt to drug populations or control the weather with chemicals.

Unlike the science of aeroplane wings, it's actually pretty straightforward to explain where vapor trails come from.

Jet engines produce water vapor in their exhaust.

When this hot vapor hits the very cold air outside, it freezes, creating a streak of tiny ice crystals in the sky.

So why do claims like this persist?

It's partly down to trust.

Unless you want to brush up on thermodynamics or buy a jet engine, at some point you're going to have to take someone's word that this is how the science works.

But conspiracy theories are also about community.

If people go against scientific consensus, it can make them feel like an independent thinker and part of a resistance.

Then there's that crucial element, the need for an explanation beyond simple coincidence.

whether we want to push the boundaries of science or push back on conspiracy theories, we need to appreciate this very human desire to explain.

I've made the mistake sometimes of neglecting this in the past.

I've given people an oversimplistic explanation for a complex process and created even more confusion than there was before.

Or in a situation with limited time, I've told people it's not possible to properly untangle the complexity involved.

And in doing so, I failed to acknowledge that very deep-rooted need to explain.

I now notice other scientists making the same mistake.

They might say, the evidence is clear, when it isn't to a lot of people.

Or they might say, it's well established this is true, without saying why it's true.

This matters because increasingly we have to navigate a world that most of us struggle to fully understand.