We've blogged before about the phenomenon of climate-induced displacement; in this week's Proceedings of the National Academy of Sciences, three Princeton researchers take a first stab at quantitatively estimating how the impact of climate change on agricultural productivity will effect migration levels. Specifically, they explore past responses to climate-driven crop failures in Mexico, and rely on statistical modeling to estimate that a 10% reduction in crop yields will lead an additional 2% of the population to emigrate. The authors predict that, depending on the warming scenarios and adaptation levels one assumes, anywhere from 1.4 million to 6.7 million adult Mexicans are likely to emigrate as a result of declines in agricultural productivity alone over the next 70 years. Though I don't take issue with the methodology, statistical models are inherently limited in their ability to fully capture the complexity of real world decisions -- here, choices concerning migration. Given the number of factors involved in migration choices, similar crop failures in the future might not have the same impact as past failures. Despite these limitations, the study offers compelling evidence that international migration due to climate-driven crop failure is likely to be significant over the coming years. How should we respond?
As IntLawGrrl guest/alumna Jane McAdam has explained, the international law of migration offers no solutions for those displaced due
to climate change. As greater and greater numbers of migrants are forced to move due to crop failure and other consequences of climate change, developed nations will need to develop a coherent response or risk being overwhelmed by irregular migration flows. In migrant-producing states, the study suggests that governments could assist subsistence farmers to become more effective -- and of course migrant-receiving states and international organizations could assist in this task. In both of these approaches, the particular needs of and risks faced by women migrants must be taken into account. Particularly with respect to displacement driven by crop failure, which will impact the very poorest women, legal solutions should ensure the physical and financial security of female migrants, and development strategies should focus on empowering rural women.
As IntLawGrrl guest/alumna Jane McAdam has explained, the international law of migration offers no solutions for those displaced due
to climate change. As greater and greater numbers of migrants are forced to move due to crop failure and other consequences of climate change, developed nations will need to develop a coherent response or risk being overwhelmed by irregular migration flows. In migrant-producing states, the study suggests that governments could assist subsistence farmers to become more effective -- and of course migrant-receiving states and international organizations could assist in this task. In both of these approaches, the particular needs of and risks faced by women migrants must be taken into account. Particularly with respect to displacement driven by crop failure, which will impact the very poorest women, legal solutions should ensure the physical and financial security of female migrants, and development strategies should focus on empowering rural women. 
