Source: BBC Radio 4: More or Less
URL: http://www.bbc.co.uk/programmes/b038zhb7
Date: 30/08/2013
Event: Climate refugee projections unquestioningly adopted by IPCC are "iffy"
Attribution: BBC Radio 4
People:
Tim Harford: Now, what are we to do with Labour's immigration spokesman Chris Bryant? It seems that every time he makes a statement, at the moment, there'll be a correction along in a minute. Earlier in the summer, he released extracts from a speech taking aim at Tesco and Next, for recruiting too many immigrants. By the time the speech was delivered, many of his claims had been withdrawn, and Mr. Bryant was "taking full responsibility". So, who's going to take full responsibility for this?
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 in the process of being afraid 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. Some of this, he says, 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, Hananh 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 Information Network, 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 labelling 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: Hannah, we've heard about his work in the past.
Hannah Barnes: Yeah. 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.
Man's voice: Dear visitor, it seems like the map you are 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 are just taking the scenic route, darling! See Honey, We're not lost. I know where we are: This way I think... mmm! [Verbatim from screen grab of UNEP website.]
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 and 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 at all - he simply took a map of the world, worked out what areas would be inundated if the sea rose, say, by 50 centimetres, and then simply assumed that all the people affected by this sea level rise would have to migrate, and a lot of them would migrate to developed countries. And really there was no basis for it.
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 a crowd over there, on the rise, and say "There's 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 there'll be forced to move. And that could well be internally.
Tim Harford: And equally, Stephen Castles didn't deny that some people have been, and will be, forced to move country.
Stephen Castles: 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: 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, back in 2011, was talking to Hannah Barnes. Now, one thing, Hannah - I thought you were our cod correspondent.
Hannah Barnes: I am, I am - it's just a bit quiet on the cod news front, at the moment.
Tim Harford: You're listening to More or Less, with me, Tim Harford. Our email address, so you can report all manner of statistical curiosities. is moreorless@bbc.co.uk.