Estimating global economic well-being with unlit settlements

Area of Science:

• Environmental Science
• Geospatial Analysis
• Socioeconomic Studies

Background:

• Nighttime lights from satellites correlate with economic prosperity globally.
• Unlit areas in developing countries often signify limited development and are frequently disregarded in analyses.

Purpose of the Study:

• To quantify the extent of human settlements lacking detectable nighttime radiance.
• To investigate the geographic distribution of these unlit settlements.
• To assess the utility of unlit settlement data for predicting socioeconomic indicators.

Main Methods:

• Integration of satellite nighttime lights data with the World Settlement Footprint dataset for 2015.
• Analysis of the percentage of unlit settlement footprints across different continents and regions.
• Development and validation of a predictive model for wealth class based on unlit settlement percentages.

Main Results:

• 19% of the global settlement footprint in 2015 had no detectable artificial nighttime radiance.
• Unlit settlements are predominantly found in Africa (39% of its footprint), the Middle East, and Asia, with rural areas showing higher percentages (65%).
• A predictive model using unlit settlement data achieved 87% accuracy in mapping wealth class for ~2,400,000 households across 49 countries.

Conclusions:

• A significant portion of human settlements globally, especially in Africa, remains unlit, indicating development disparities.
• The absence of nighttime radiance in settlements is a strong indicator of lower socioeconomic status.
• This research provides a novel method for mapping and understanding wealth distribution in data-scarce regions.