City Lights Seen From Space Reveal How Countries Change
A post at Wired Science describes a recent presentation by the head of the National Geophysical Data Center’s Earth Observatory Group, on how economic and political developments are illustrated by changes in artificial illumination captured by long-term satellite observation.
For instance, the satellites saw a steep decline in lighting in Rwanda in 1994 and the following years, reflecting that country’s civil conflict and genocide. Similarly, a civil war in Cote d’Ivoire from 2002 to 2004 severely darkened the country, with lights only returning in recent years. As well, increased lighting in Iraq in 1999 corresponded to the UN lifting import restrictions at the time, while external investment in Afghanistan led to increases in satellite-observed lighting starting in 2002.
Perhaps not surprisingly, countries undergoing rapid growth, such as China, had a high correlation between lighting and both GDP and population. In contrast, highly developed countries, such as the U.S. and Western Europe, showed fairly stable lighting patterns that didn’t shift despite increases in population and GDP.
This effect is clearly visible in the contrast between China and South Korea, Japan and Taiwan from 1992 to 2010 (click through to view a time-lapse sequence). North Korea remains almost entirely dark throughout.
A second sequence at Wired shows similar images of India and its neighbours. See more on the observation of city lights from NASA.gov, and timelapse videos taken from the International Space Station showing flyovers of various regions around the world, as well as orbital views of the Northern and Southern lights.