Welcome to the documentary from the BBC World Service.

I'm John Murphy, and for assignment, I'm in France diving into the world of wine.

We are in the Agli Valley.

The Agli Valley.

Agli is the name of the river.

It comes from eagle,

because there are a lot of eagles in this part of France, southern France.

The Agli Valley is a very interesting valley for winemaking

because first there are a lot of different types of stones, of earth,

which gives the taste of the wine

and of the fruits as well. But it stopped raining three years ago, four years ago. It's the most

important problem we have ever had. Sebastian D'Angou is driving his battered four-by-four

around his vineyards above the valley with its dry riverbed,

pointing out the different plots he and his brother Benoit cultivate.

Like many winemakers across France, they're struggling with a rapidly changing and unpredictable climate.

It's extreme.

The climate, it's becoming more and more extreme.

When it rains, it rains too much.

When the wind blows, it blows so strongly that it breaks everything.

And when it's dry, it's too dry.

When it's hot, it's too hot. When it's hot, it's too hot.

So we have to adapt to these conditions and to think about what we can do, what we can do.

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