# Empirical View
# Price of Light from 1300 until today
# Price of light by energy source from 1300 until today
Price of Light by source from 1300 until today1
Trends in the prices of energy for lighting and of lighting services, 1300-2000 – Fouquet and Pearson (2012)2
# Consumption of Light by source over the last 300 years
Consumption of lighting from candles, gas, kerosene and electricity in the United Kingdom (in billion lumen-hours), 1700-2000 – Fouquet and Pearson (2007)3
# Satellite Images of the Earth at Night
Composite image of the Earth at night – NASA4
# Correlates, Determinants & Consequences
Several papers have recently shown that light density at night reflects well standards of living. Both across geographic regions and across time. Some of these papers are:
- Christopher Small & Christopher D. Elvidge (2013) – Night on Earth: Mapping decadal changes of anthropogenic night light in Asia. International Journal of Applied Earth Observation and Geoinformation. Volume 22, June 2013, Pages 40–52. Online here.
- Henderson, Storeygard, and Weil (2011) – “Measuring Economic Growth from Outer Space,” American Economic Review, 102(2), 994-1028. This paper is online here.
- Chen and Nordhaus (2011) – “Using Luminosity Data as a Proxy for Economic Statistics,” Proceeedings of the National Academy of Sciences, 108(21), 8589—8594.
- Tilottama Ghosh, Rebecca L. Powell, Christopher D. Elvidge, Kimberly E. Baugh, Paul C. Sutton and Sharolyn Anderson (2010) – Shedding Light on the Global Distribution of Economic Activity. The Open Geography Journal, 2010, 3, 147-160 147.
Striking is the difference between North and South Korea by night shown in the satellite image below. It illustrates the point about the correlation between night time light and living conditions in terms of health, food provision, and poverty.
North and South Korea at night, 2012 – NASA5
# Change of night light over time to measure poverty
As a country develops the luxury of having light at night becomes available to more and more people. This simple fact was used by Maxim Pinkovskiy and Xavier Sala-i-Martin to study how poverty levels changed by studying how nighttime light – visible in satellite images – changed over time. The comparison of South Asia in 1994 and 2010 is taken from their study published in the Quarterly Journal of Economics in 2016.6
# Data Sources
NASA’s Visible Earth catalog, online here, is a great source for night images of the earth.