The New York Times today has an op-ed on climate change and immigration by Sujatha Byravan, president of the Council for Responsible Genetics, and Sudhir Chella Rajan, head of the Global Politics and Institutions Program at the Tellus Institute. The op-ed revisits an argument made by the authors recently in Nature.

Byravan and Rajan argue that one of the consequences of human-caused climate change “will be rising seas, which in turn will generate a surge of “climate exiles” who have been flooded out of their homes in poor countries. How should those of us in rich countries deal with this wave of immigrants? The fairest solution: allowing the phased immigration of people living in vulnerable regions according to a formula that is tied to the host country’s cumulative contributions to global warming.”

This op-ed is worth commenting on because it actually talks about policy, and does not take us into the cul-de-sac of “global warming: yes or no?”. So let’s discuss their recommended policy option. To summarize my critique, Byravan and Rajan take a complicated issue of great importance, displaced peoples, and argue as if a human-caused climate change aspect of this issue can be considered in isolation of that larger problem. This, in a nutshell, represents the core pathology of current discussion of climate policies.

Byravan and Rajan proposal is as follows: “So no matter what we do, a wave of climate change exiles is inevitable. One option for dealing with this is to tighten our borders and inure ourselves to the exiles’ cries for help. A more sensible, and just, approach is for the top greenhouse gas emitters – including China and India – to grant entry to the up to 200 million people who could lose their homes to rising seas by 2080. How many should go where? Under our formula, the top cumulative emitter, the United States, would absorb 21 percent of the climate-change exiles a year; the smallest of the 20 major emitters, Venezuela, would absorb less than 1 percent. If such a program were to start in 2010, the United States, for example, would have to be prepared to accept 150,000 to a half-million immigrants a year for the next 70 years or so (to put that in context, the United States now has one million legal immigrants annually).”

My critique of their proposal has two parts. First, Byravan and Rajan’s numbers are based on some highly dubious assumptions. They suggest that based on its proportion of historical greenhouse gas emissions the US might be responsible for accepting 21% of climate change immigrants, which they calculate as 150,000 to 500,000 per year. The Times op-ed doesn’t say where these numbers come from but we can see their origin from what Byravan and Rajan said in Nature:

“Estimates suggest that roughly 50 million to 200 million people will be displaced by the 2080s, owing to the direct impacts of climate change under a plausible range of emissions scenarios (R. J. Nicholls Glob. Environ. Change14, 69-86; 2004). Assuming that all these climate-change exiles are absorbed by the top ten ‘emitter’ countries, new annual immigrants would range from a few thousand for the Czech Republic to about three-quarters of a million for the United States.”

So 150,000 immigrants refer to the 50 million-over-70-year scenario and the half million immigrants refers to the 200-million-over-70-year scenario. Setting aside uncertainties in projecting future sea-level rise and its impacts on coastal inhabitants, the dodgiest assumption here is that all people projected to be displaced by human caused climate change will seek to relocate in rich countries.

The Indian Ocean tsunami does provide some experience that might be useful in exploring how many displaced coastal residents from developing countries actually seek to migrate to rich countries. According to the Red Cross more than 1.6 million people were displaced by the tsunami. Have all of these people sought to migrate to rich countries? It seems highly unlikely. According to a just-released US AID study in the aftermath of the tsunami, “despite the devastation, the desire for self-sufficiency and a return to normality has led some people to return home already without help from the government or aid agencies. Most people said that if they could not return home, they would like to be relocated as close as possible to their original homes and jobs if the government could guarantee them legal ownership of the land on which their new homes would be built.”

A second issue with the numbers is that Byravan and Rajan seek to anchor attention to the current level of United States immigration of ~1 million per year. Under their proposal this would result in a 15% to 50% increase over present day levels, numbers surely designed to capture attention. But a more appropriate base rate is the number of displaced people worldwide. The U.N. High Commission for Refugees estimates in recent years that there are ~17-20 million people who are in some way displaced. Even assuming the worst case assumptions of Nicholls study, it would seem that migration of people associated with climate change is a subset of a much larger challenge of displaced peoples, rather than vice versa.

And this leads to my second criticism of the Byravan and Rajan op-ed, it seeks to redefine a serious humanitarian issue as an issue of human caused climate change. This is (yet) another example of attempts to gerrymander the climate change issue as if it can be addressed in isolation from issues of disease, disasters, poverty, water resources, energy use and now migration. Under Byravan and Rajan’s proposal that climate change refugees be allocated to rich countries I wonder how they might identify a “climate change refugee” from the much larger population of displaced peoples. So as to distinguish them from the tens of millions of other displaced people, presumably these future immigrants to the rich world need some proof that their dislocation resulted from the historical emissions of greenhouse gases and not poverty, war, poor governance, bad luck or any this else.

Less charitably, invoking concerns about future migrations of developing world peoples to the north comes close to exploiting existing fears and passions about immigration as a rhetorical political strategy to garner support for action climate change. Issues of displaced peoples and immigration are tremendously important. Climate change is also important. But conflating the two is unlikely to lead to effective policy development in response to immigration or climate impacts.