A bomb whose creation would tip the scales of global power.

A nuclear physicist who sought to redress the balance.

The bomb, a podcast from the BBC World Service.

These are two available now.

Hello, I'm James Reynolds on the BBC World Service.

And this is BBC OS Conversations on Extreme Heat.

As many countries around the world experience heat waves,

we hear from people in Qatar and Pakistan,

where temperatures above 40 degrees are common,

about how they navigate their daily lives in the heat.

Plus, how TV meteorologists in South Africa and Spain explain climate change.

We are talking about climate change from a health point of view.

Here in Spain, we estimate that almost 500 people

could have died because of heat during this week.

If you've glanced at a map of global temperatures recently,

you'll have noticed that that map is so red

that it looks like parts of the Earth are on fire.

Experts have even warned that Western France is facing a heat apocalypse.

Across the rest of the country, as well as Spain, Portugal,

and Greece, firefighters continue to battle wildfires

that have destroyed forests, homes, and forced thousands of people to flee.

It's not just Europe, of course.

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