## Illuminating Economic Growth Using Satellite Images – IMF F&D ## Source details **Canonical URL:** [Illuminating Economic Growth Using Satellite Images – IMF F&D](https://www.imf.org/en/publications/fandd/issues/2019/09/satellite-images-at-night-and-economic-growth-yao) ## Other formats - [Markdown version](/en/publications/fandd/issues/2019/09/satellite-images-at-night-and-economic-growth-yao/index.md) - [Structured JSON version](/en/publications/fandd/issues/2019/09/satellite-images-at-night-and-economic-growth-yao/index.json) - [Bundle manifest](/en/publications/fandd/issues/2019/09/satellite-images-at-night-and-economic-growth-yao/bundle-manifest.json) ## Bibliographic details - Authors: JIAXIONG YAO - Published: September 1, 2019 --- ### Overview of night lights as economic data - Satellite "night lights" images have been used to study human activity and natural events for almost 30 years. - Economists have used night lights in the past decade to gauge economic growth, map poverty, analyze inequality, and answer questions where conventional data are lacking. - Each pixel represents an area of less than one square kilometer and is associated with a digital number measuring brightness at night; aggregating pixel values for a country produces an indicator of that country's night-time activity over time. ### How night lights reflect the changing economy - Night lights capture two broad aspects: - Spatial expansion or contraction: in growing economies more areas are lit and more pixels record light; in regions affected by conflict more patches go dark and pixels lose light. - Intensification: urbanization, city agglomeration, and infrastructure modernization increase brightness per pixel. - Empirical relationships: - Rich countries are generally brighter than less developed countries, with notable exceptions (e.g., Nordic countries are among the brightest per capita; Japan appears scarcely brighter than pre–Arab Spring Syria, likely due to energy conservation habits and high population density). - When accounting for country-specific characteristics of night lights, a transition emerges: early development emphasizes physical capital (infrastructure that emits light at night); advanced economies rely more on scientific and technological innovation, where night lights grow only about half as fast as GDP in advanced economies. ### Use of night lights where official statistics are weak - Night lights can reestimate GDP for conflict-stricken countries by comparison with countries at various development stages. - Findings from such reestimation: - Night-light-based GDP measures often indicate faster economic deterioration during conflict than official data show. - Night-light-based measures also suggest a stronger bounce-back after conflict ends. - The informal economy likely contributes to postconflict dynamics observed in night-light measures. ### Data scale and technological implications - Data scale described in the source: - An individual country such as the United States can consist of hundreds of millions of data points when each pixel is treated as a data point. - With more than 200 countries and regions, the Earth's land surface contains almost a billion data points for a single early satellite image of very coarse resolution. - The number of data points would grow exponentially with more frequent releases and ever-finer resolution images; there are already hundreds of them taken in the past and many more to be taken in the future. - Night lights have been illuminating the Earth for more than a century. - Opportunities from big geospatial data: - Advances in data science, including machine learning, can analyze patterns to support decision-making. - Granular satellite data can be harnessed to study local effects, spatial spillovers, and remote economic activity where ground information is scarce. - Private firms (examples cited in the source: DigitalGlobe and Orbital Insight) already apply data-science techniques to such imagery. ### Conclusions and policy implications - Night lights provide a valuable complementary indicator of economic activity, especially where conventional statistics are lacking or unreliable. - Policy-relevant implications highlighted: - Use night-light data to improve monitoring of economic deterioration and recovery in conflict-affected areas. - Leverage machine learning and other data-science methods to extract actionable insights from expanding satellite and geospatial datasets. - Seize the opportunities of big data to guide smarter policies that improve understanding of the economy and support development objectives. - The author emphasizes that as we enter the age of big data, opportunities abound and should be harnessed to make "this world a better and brighter place." *JIAXIONG YAO, F&D Magazine, September 2019.* --- ## Content in this bundle - **أضواء النمو الاقتصادي** - [أضواء النمو الاقتصادي (Markdown version)](/-/media/files/publications/fandd/article/2019/september/ar/yao.pdf.md){rel="alternate" type="text/markdown"} - [أضواء النمو الاقتصادي (PDF)](/-/media/files/publications/fandd/article/2019/september/ar/yao.pdf){rel="external" type="application/pdf"} - **La luminosidad del crecimiento económico ● Finanzas y Desarrollo ● Septiembre de 2019** - [La luminosidad del crecimiento económico ● Finanzas y Desarrollo ● Septiembre de 2019 (Markdown version)](/-/media/files/publications/fandd/article/2019/september/es/satellite-images-at-night-and-economic-growth-yao.pdf.md){rel="alternate" type="text/markdown"} - [La luminosidad del crecimiento económico ● Finanzas y Desarrollo ● Septiembre de 2019 (PDF)](/-/media/files/publications/fandd/article/2019/september/es/satellite-images-at-night-and-economic-growth-yao.pdf){rel="external" type="application/pdf"} - **Lumière sur la croissance économique** - [Lumière sur la croissance économique (Markdown version)](/-/media/files/publications/fandd/article/2019/september/fr/satellite-images-at-night-and-economic-growth-yao.pdf.md){rel="alternate" type="text/markdown"} - [Lumière sur la croissance économique (PDF)](/-/media/files/publications/fandd/article/2019/september/fr/satellite-images-at-night-and-economic-growth-yao.pdf){rel="external" type="application/pdf"} - **Освещая экономический рост – Финансы и развитие – сентябрь 2019 года** - [Освещая экономический рост – Финансы и развитие – сентябрь 2019 года (Markdown version)](/-/media/files/publications/fandd/article/2019/september/ru/satellite-images-at-night-and-economic-growth-yao.pdf.md){rel="alternate" type="text/markdown"} - [Освещая экономический рост – Финансы и развитие – сентябрь 2019 года (PDF)](/-/media/files/publications/fandd/article/2019/september/ru/satellite-images-at-night-and-economic-growth-yao.pdf){rel="external" type="application/pdf"} - **Illuminating Economic Growth Using Satellite Images – IMF F&D** - [Illuminating Economic Growth Using Satellite Images – IMF F&D (Markdown version)](/-/media/files/publications/fandd/article/2019/september/satellite-images-at-night-and-economic-growth-yao.pdf.md){rel="alternate" type="text/markdown"} - [Illuminating Economic Growth Using Satellite Images – IMF F&D (PDF)](/-/media/files/publications/fandd/article/2019/september/satellite-images-at-night-and-economic-growth-yao.pdf){rel="external" type="application/pdf"} - **点亮经济增长 - 《金融与发展》2019年9月号·第56卷·第3期 - 国际货币基金组织季刊** - [点亮经济增长 - 《金融与发展》2019年9月号·第56卷·第3期 - 国际货币基金组织季刊 (Markdown version)](/-/media/files/publications/fandd/article/2019/september/zh/satellite-images-at-night-and-economic-growth-yao.pdf.md){rel="alternate" type="text/markdown"} - [点亮经济增长 - 《金融与发展》2019年9月号·第56卷·第3期 - 国际货币基金组织季刊 (PDF)](/-/media/files/publications/fandd/article/2019/september/zh/satellite-images-at-night-and-economic-growth-yao.pdf){rel="external" type="application/pdf"} --- _Source: https://www.imf.org/en/publications/fandd/issues/2019/09/satellite-images-at-night-and-economic-growth-yao_