Just before this BBC podcast gets underway, here's something you may not know.

My name's Linda Davies and I Commission Podcasts for BBC Sounds.

As you'd expect, at the BBC we make podcasts of the very highest quality featuring the most knowledgeable experts and genuinely engaging voices.

What you may not know is that the BBC makes podcasts about all kinds of things like pop stars,

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This is the Witness History Podcast from the BBC World Service. I'm Ashley Byrne.

All this week we're looking at environmental history in the run up to the United Nations Conference on Climate Change, COP26. Today I'm bringing you a

program from our archives. I spoke to the American scientist James Hanson who in

June 1988 helped alert the world to the reality of climate change.

Altogether, this evidence represents a very strong case, in my opinion, that the greenhouse effect has been detected

and it is changing our climate now.

On the 23rd of June 1988, the temperature was soaring in Washington, D.C.

Scientists Professor James Hanson was giving testimony to the United States

Senate Committee on Energy and Natural Resources. By the time he was finished

he had put the greenhouse effect and climate change on the worldwide agenda.

The world is heating up and there's not much doubt it will continue to heat up until some fairly

urgent action is taken by the industrialized world to slow down the emission of the gases which

cause the so-called greenhouse effect. Professor James Hanson had actually begun

his career looking at climates millions of miles from Earth.

I thought what could be more exciting than studying what the clouds of Venus are made of.

But in the late 1970s we realized the Earth's atmosphere is changing, which makes the Earth a more interesting planet than the others.

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