Bright Lights, Big City?
Economists have discovered the potential of lights at night viewed from space to illuminate patterns and trends in economic activity, particularly in less developed regions with limited economic statistics. This map shows the strong correspondence between where night-time lights are brightest and dense population centers. But poor areas that are as densely populated as rich areas often do not display bright night lights, due to their lower levels of economic activity.
Some researchers have therefore sought to use light intensity per capita, estimated by combining satellite observations with census data, to assess poverty levels. For example, in the map on the right, brightness dips significantly when crossing from South to North Korea despite high population densities in the southernmost tip of North Korea.
One might expect that the highest rates of economic growth would be found in coastal megacities. Former CIESIN staff member Adam Storeygard, now an economist and assistant professor at Tufts University, has been using nighttime lights data to ask questions about economic development in Africa. When he and his colleagues looked at growth rates in coastal regions of Africa versus those in land-locked areas, they found that, counter to expectation, the larger, coastal cities were growing more slowly. They also wanted to see if high rates of malaria in the population were a brake on economic growth, but again they were surprised to find that, in areas where malaria control had succeeded, there was no substantial increase in lights over time. (See “Prosperity Shining,” in Sensing our Planet NASA Earth Science Research Features 2012).
For those interested in learning more about night-time lights data and their application, a thematic guide to nighttime lights is available from the NASA Socioeconomic Data and Applications Center (SEDAC) operated by CIESIN. __________________________________________________________________________________
This blog is part of the Map of the Month blog series produced by the Center for International Earth Science Information Network (CIESIN). The map and commentary were developed by geographic information specialist Linda Pistolesi, with senior research associate Alex de Sherbinin, associate research scientist Susana Adamo, geographic information specialist Tricia Chai-Onn, and communications coordinator Elisabeth Sydor.