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In 1972, a group
of eminent scientists
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sat down to write a letter to
the President of the United States.
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They were frightened.
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The Earth's climate
seemed to be going haywire.
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They worried that war, pestilence
and famine were on the way.
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For the first time, climate change
had become a hot political topic.
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The letter warned the President
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he had to prepare
not for global warming,
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but for the complete opposite -
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a new ice age.
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Yup, 36 years ago,
a lot of leading scientists
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really thought that an ice age
was just around the corner.
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And yet today, they're all
apparently convinced
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that global warming is
the big threat.
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But if scientists were
so wrong back then,
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how can we be sure
they've got it right today?
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In this series, I'm going to
explore some simple, big questions.
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How do we know
the climate is warming up?
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How do we know
humans are causing it?
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And how do we know
what's going to happen next?
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As the story
of global warming has unfolded,
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we've learnt of the very nature
of scientific truth
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and about how
that has been falsified,
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manipulated, twisted,
and even bought.
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...
