Counting climate migrants

Summary

More or Less — "Counting climate migrants"

BBC Radio 4 — August 31, 2013
Host: Tim Harford
Correspondent: Hannah Barnes
Guests: Chris Bryant (Britain's Shadow Immigration Minister), Alex Randall (Climate Outreach), Stephen Castles (International Migration Institute, Oxford), Norman Myers (environmental scientist)

Overview of the Episode

In this episode, Tim Harford and correspondent Hannah Barnes dissect commonly cited statistics about climate-induced migration. The focus is on examining claims, often repeated in political and media discourse, about the scale of current and future "climate refugees." The team critiques the origins and credibility of dramatic migration figures, striving to separate sound evidence from well-intentioned but unsubstantiated warnings.

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Key Discussion Points and Insights

1. The Claim: 20 Million Displaced by Climate Change in 2008 (00:39-02:36)

• Chris Bryant's Statement:
  Chris Bryant, Britain’s Shadow Immigration Minister, warns of "mass migration as yet unparalleled" (00:31), citing a UN estimate that "in 2008, 20 million people were displaced by climate change" (00:54).
• Expert Critique – Alex Randall (Climate Outreach):
  • Highlights that this figure is essentially a tally of all people displaced by any natural disaster, labeled as "climate refugees."
  • Notes the problematic assumption that all natural disasters are directly attributable to climate change.
  • Stresses the lack of a straightforward link: "It's certainly not the case that we can attribute all of those individual displacements to climate change alone." (02:19)
• Migration Patterns:
  • Randall points out that most people displaced by disasters are not seeking long-term relocation abroad:

    "People tend to move short distances for a short period of time and then move back." (02:45)

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2. The Claim: 200 Million Future Climate Refugees (03:00-04:14)

• Origins of the Figure:
  This alarming prediction comes from UN reports but, as Barnes uncovers, lacks clear authorship or defensible methodology.
• UN's Response:
  UN declines to stand by the figure:

  "The UN told me it cannot comment in any way on the accuracy of a figure we did not produce." (04:14)

• Expert Perspective – Alex Randall:
  • The concept of mass, cross-border migration is likely inaccurate.
  • Typical response to environmental stress:

    "Rather than all of them at once upping sticks and moving to another country... one or two household members will move, probably within their own country and probably to a big urban centre, to a city nearby." (03:31)

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3. Where the Big Numbers Come From: Norman Myers (04:24-07:47)

• Norman Myers’ Estimates:
  Myers’ projections (50 million climate refugees by 2010; 200 million by 2050) were widely cited but are methodologically weak.
• Stephen Castles’ Critique (International Migration Institute):
  • Myers "simply took a map... worked out what areas would be inundated... and then simply assumed that all the people affected... would have to migrate" (05:58).
  • Describes this as "really not permissible" and lacking empirical evidence.
• Historical Embarrassment:
  • UN websites and other bodies quietly removed references to the 50 million figure after it became clear that it could not be substantiated (04:33-05:36).
• Defensive Stance – Norman Myers:
  • Admits the difficulty of proving such numbers:

    "I would not like to be the person who tries to come up with an exact precise figure, but... it will be better for us to find we have been roughly right than precisely wrong." (07:10)

  • Uses analogy:

    "You can't prove that smoking causes cancer. Science is never, never, ever completely final. It's always a bit iffy." (07:53)

  • Harford quips:

    "Iffy, good choice of word." (08:02)

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4. The Reality: What Do We Know About Climate-Induced Migration? (08:05-08:52)

• Internal vs. International Migration:
  Myers’ own definitions often include internal movements, not the international mass exodus the rhetoric suggests.
• Scale of the Problem:
  • Stephen Castles provides real-world examples (e.g., small Pacific islands like Tuvalu and Kiribati) but notes that actual numbers involved are small (tens of thousands rather than millions).

  "But that's tens of thousands, not tens of millions." (08:49) "Absolutely, yes." (08:51)

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Notable Quotes & Memorable Moments

• On Attribution of Disasters to Climate Change:
  Alex Randall (02:19):

  “The relationship between natural disasters and climate change is complicated. It’s certainly true that climate change might be making some of those particular disasters more likely, but it’s certainly not the case that we can attribute all those individual displacements to climate change alone.”

• On Mass Migration Myths:
  Alex Randall (03:31):

  "What’s likely to happen... is that one or two household members will move, probably within their own country and probably to a big urban centre..."

• On the Creation of the 200 Million Figure:
  Stephen Castles (05:58):

  "[Myers] simply took a map...and then simply assumed that all the people affected by this sea level rise would have to migrate...There was no basis for it...Where is the empirical evidence?"

• On Scientific Uncertainty:
  Norman Myers (07:53):

  "You can't prove that smoking causes cancer. Science is never, never, ever completely final. It's always a bit iffy."

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Important Segment Timestamps

• 00:39: Chris Bryant warns of mass migration due to climate change.
• 01:49: Introduction of Alex Randall as a critic of inflated migration numbers.
• 02:36: Insight into actual migration patterns post-disaster.
• 03:00: Discussion of the 200 million figure.
• 04:14: Hannah Barnes reports that the UN won’t defend or confirm the statistic.
• 05:58: Stephen Castles outlines the flaws in Myers’ methodology.
• 07:10-07:53: Norman Myers defends his approach and the difficulties inherent in such predictions.
• 08:49: Stephen Castles and Hannah Barnes clarify actual likely migration scales.

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Tone and Delivery

• Analytical, skeptical, gently humorous (see Harford's asides).
• Carefully avoids alarmism; emphasizes the complexity and uncertainty in migration data.
• Engages with original sources and their critics in a fair and thorough way.

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Summary Takeaway

While climate change may indeed increase human migration pressures, the widely cited numbers (20 million displaced in 2008; 200 million “climate refugees” in the future) are based on shaky assumptions and broad definitions. Most climate-linked migration is likely to be internal and on a much smaller scale than the headline figures suggest. The episode emphasizes the need for caution and rigor in both the communication and use of climate migration statistics.

Transcript

[BBC Announcer]

Thank you for downloading from the BBC. For details of our complete range of podcasts and our terms of use, go to bbcworldserveys.com podcasts

[Hannah Barnes]

this is the short edition of More or Less, first broadcast on the BBC World Service.

[Tim Harford]

Hello and welcome to More or Less on the BBC World Service, the programme which makes sense of numbers in the news and in life. Hi, I'm Tim Harford. This week, we take a look at what problems climate migration might pose.

[Chris Bryant]

So if we get climate change wrong, there is a very real danger we shall see levels of mass migration as yet unparalleled.

[Tim Harford]

That's Chris Bryant, Britain's Shadow Immigration Minister, warning that millions of people around the world will be forced to flee their homes and, in their droves, move to countries less affected by environmental problems. Now, some of this has already happened.

[Chris Bryant]

The United nations estimates that in 2008, 20 million people were displaced by climate change, compared to 4.6 million by virtue of internal conflict or violence.

[Tim Harford]

But much more is to come.

[Chris Bryant]

You can imagine that the UN estimates of 200 million such refugees, more than the total number of worldwide migrants today, may be about right.

[Tim Harford]

Now, in fairness to Mr. Bryant, he didn't just make that claim up, it did indeed come from the United Nations. But we still suspect that some kind of retraction may be necessary. Alas, here at More or Less, we have a climate migration correspondent, Hannah Barnes. Hannah, you've done this before. You specialise in taking the heat out of these kinds of statistics.

[Hannah Barnes]

That's right, but it's not just me. Various experts in the field and even concerned charities have to spend a lot of their time correcting overblown statements like these.

[Tim Harford]

Let's start with the claim that 20 million people were displaced by climate change in 2008.

[Hannah Barnes]

And a surprising critic of that number, Alex Randall, works for the Climate Outreach and a charity which aims to raise awareness of climate refugees and their needs. So you might think he'd be shouting the same alarming numbers from the rooftops, but he's not.

[Alex Randall]

What Chris Bryant was quoting in his speech was a kind of adding up all of the people who've been displaced by any kind of natural disaster and labeling them climate refugees. And that's problematic for a number of reasons. Firstly, because the relationship between natural disasters and climate change is complicated. It's certainly true that climate change might be making some of those particular disasters more likely, but it's certainly not the case that we can attribute all of those individual displacements to climate change alone.

[Hannah Barnes]

And Even if all 20 million people had been displaced by climate change, they're unlikely to be looking to set up home in a new country.

[Alex Randall]

The idea that in the event of a natural disaster, people will immediately move long distances and permanently is mistaken. People tend to move short distances for a short period of time and then move back.

[Tim Harford]

So let's take a look at this claim from the United nations, quoted by Chris Bryant, that 200 million people will become climate refugees in future.

[Hannah Barnes]

Yeah. And what we're really talking about here is people who have to leave their homes because their lives and livelihoods are being adversely affected by climate change. So not just because of sudden natural disasters, but because of a slow creep changing weather systems, say, or rising sea levels. But many experts don't expect this to cause mass migration. Alex Randall explains why.

[Alex Randall]

If it becomes increasingly difficult for a farming community to sustain their livelihood by growing the crops that they have been, what's likely to happen is that in response to that, rather than all of them at once upping sticks and moving to another country, the likely response is that one or two household members will move, probably within their own country and probably to a big urban centre, to a city nearby. They'll then work and send money back to their family.

[Tim Harford]

So migration tends to be relatively local and small scale. Now, I was fascinated by the way the UN justifies its claim that 200 million people will become climate refugees.

[Hannah Barnes]

It doesn't. The UN told me it cannot comment in any way on the accuracy of a figure we did not produce.

[Tim Harford]

So they're happy to use the figure, just not to defend it.

[Hannah Barnes]

Quite. Now, the figure is the work of a scientist called Norman Myers, who's based in Oxford in the uk.

[Tim Harford]

Now, we've heard about his work in the past.

[Alex Randall]

Yep.

[Hannah Barnes]

Back in 2011, we looked at his claim that 50 million people would become climate refugees by 2010. It had been quoted by some influential institutions, but one year on, there was scant evidence that these people existed. The UN had a map showing this prediction on the website, but hastily took it down. We discovered when it started to get attention initially, there was no explanation as to why it had disappeared. Just a totally bizarre message came up when you went to click on the link.

[Narrator/Interviewer (voiceover)]

Dear Visitor, it seems like the map you're navigating by is maybe not fully up to date or that it might have an error in it. Or is it that your GPS is not loaded with the correct data? We're just taking the scenic route, darling. See, honey, we're not lost. I know where we are. This way, I think.

[Norman Myers]

Hmm.

[Tim Harford]

I love it when our investigations take a surreal turn.

[Hannah Barnes]

Well, eventually the fog lifted and a spokesman for the United Nations Environment Programme told me the map had been removed because it was wrong.

[Tim Harford]

They had funded the research it was based on, though.

[Hannah Barnes]

They had. And this work had been unquestioningly adopted by all sorts of eminent bodies like the Intergovernmental Panel on Climate Change. But some academics had doubted his numbers from the start. Stephen Castles from the International Migration Institute at Oxford University outlined some of his concerns to me at the time.

[Stephen Castles]

Norman Myers, who I know we've discussed together, is an environmentalist. And I think his objective in putting forward these dramatic projections was to really scare public opinion and politicians into taking action on climate change, which, of course, is a very laudable motive. But the problem was that he really used a method to make projections that is really not permissible. He simply took a map of the world, worked out what areas would be inundated if the sea rose, say by 50 centimeters, and then simply assumed that all the people affected by this sea level rise would have to migrate and that a lot of them would migrate to developed countries. And really, there was no basis for it. People in the migration and refugee field were very shocked by that. And we asked, where is the empirical evidence for that? And of course, there isn't any.

[Tim Harford]

And the 200 million figure was calculated in the same way?

[Hannah Barnes]

Yes. It's his projection for the number of climate refugees there'll be by 2050.

[Tim Harford]

So he said 50 million by 2010 and 200 million by the time climate change takes hold.

[Hannah Barnes]

Yes. And he defended his methods to us at the time.

[Norman Myers]

It's very difficult to say how many there are and where are they, and to point out to a crowd over there on the horizon, say, those are environmental refugees. It is difficult. I would not like to be the person who tries to come up with an exact precise figure, but in the long run, I do believe very strongly that it will be better for us to find we have been roughly right than precisely wrong. I would be very suspicious of somebody who said, where are they? I think it would be much harder to demonstrate that there aren't any of these environmental refugees than to demonstrate that there are environmental refugees.

[Hannah Barnes]

But if you can't prove that there are, then we shouldn't be making the statement, should we? We can't prove it.

[Norman Myers]

Well, you can't prove that smoking causes cancer. Science is never, never, ever completely final. It's always a bit iffy.

[Tim Harford]

Iffy, good choice of word.

[Hannah Barnes]

Well, to be fair to Norman Myers, he did make it clear in his research that not everyone he classes as an environmental refugee will flee their country. He just said that they'll be forced to move and that could well be

[Tim Harford]

internally and equally, Stephen Castles didn't deny that some people have been and will be forced to move.

[Stephen Castles]

Country we do have some cases where places have become or are likely to become uninhabitable. There are these very small Pacific islands like Tuvalu and Kiribati, but of course the populations there are very small. We're talking about a few thousand people, ten thousand at the very most there. One would say migration to New Zealand or Australia might be the long term solution for at least some of those people.

[Hannah Barnes]

But that's tens of thousands, not tens of millions.

[Stephen Castles]

Absolutely, yes.

[Tim Harford]

Stephen Castles from Oxford University's International Migration Institute, who was talking in 2011 to Hannah Barnes. If there are any numbers you'd like us to take a closer look at, do please email us. Our address is more or lessbc.co.uk, and you can also sign up for a free download of our programmes at our website, bbcworldservice.com more or less There are

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