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Hello, this is 6 Minute English from BBC Learning English, I'm Sam.

And I'm Rob. When Sarah Ott was growing up in Florida in the 1990s, she loved playing in nature.

She picked up litter in the street and took it home to recycle.

But later, in college, Sarah became surrounded by people in her community who didn't share her love of the environment.

People who didn't believe that climate change was real. And slowly, Sarah started to doubt it as well.

Climate deniers, people who don't believe that climate change is happening, or that it isn't caused by humans,

make up around 9% of the American population, according to some estimates.

Now, Sarah works as a climate campaigner at the US National Centre for Science Education,

teaching children the science behind climate change. But her journey there was a difficult one.

And she lost many friends on the way.

In this programme, we'll be discussing climate deniers and finding out how to talk with people who doubt the science of global warming.

And as usual, we'll be learning some new vocabulary as well.

But before that, I have a question for you, Rob.

Whatever climate deniers think, there is strong agreement on the issue among scientists on the intergovernmental panel on climate change, the IPCC.

So what percentage of the world's scientific community agree that climate change is real?

Is it A, 79%, B, 89%, or C, 99%?

Oh, I'll have a guess and I'll say it's 99%.

Okay, I will reveal the answer later in the programme, Rob.

Marco Silva is a climate disinformation reporter for the BBC.

He told BBC World Service programme the climate question what he's learned about reporting on the issue from around the world.

It is quite important to make here a very clear distinction between being wrong, ill informed about climate change and being a full-blown climate denier.

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