High-resolution satellite data can very precisely assess the status of poverty at the household level in rural areas of developing countries, according to a study. If countries are to achieve the UN Sustainable Development Goals, it is particularly important to track the living conditions in poor nations around the world where the future population growth is highest, according to a study published in the journal PNAS.
It can be difficult to make a global assessment of poverty and poor economic conditions, but an eye in the sky can provide a good hint of the living conditions of populations, researchers said. "Based on high-resolution satellite images, we can very precisely assess the status of poverty at household level in rural areas in developing countries," said Jens-Christian Svenning, a professor at the Aarhus University in Denmark.
In an agricultural area in Kenya, the researchers measured, among other things, the size of buildings and areas of uncultivated soil and the length of the growing season on a number of family-run farms.
The images also reveal how people use the landscape around their homes and how this changes over time.
The researchers show that a thorough analysis of satellite images can explain 62 per cent of the variation in the economic conditions of the individual households.
As satellite images are relatively cheap and increasingly freely available, the study demonstrates that space-based monitoring is a cost-effective method to track socio-economic development as a supplement to expensive household surveys with interviews.
In particular, the use of satellite data makes it possible to analyse the economic development at much greater geographical scale and with a high temporal frequency.
"The use of satellite images makes it much, much cheaper to keep track of how far we are in reaching the UN's goals for sustainable development," said Gary R Watmough, who headed the research and is now employed at the University of Edinburgh, Scotland.
"If conventional assessments of the households' economic conditions were used, the cost would be more than USD 250 billion," Watmough said.