As sanctions against North Korea have increased, authorities have responded by redistributing wealth and economic activity to urban centers, a recent study suggests.

For the paper, Yong Suk Lee, assistant professor of economics at Williams College in Massachusets, used night-time satellite images from 1992 to 2010 to study the effects of sanctions on the geographical distribution of economic activity in North Korea.

Using luminosity as a proxy for economic development, and cross-referencing with a sanctions index built around international responses to North Korean provocations, the study found that as sanctions increase, authorities move economic activities to urban