Most people affected by Nepal quake have returned home: Study

Most of the people who had left their homes after the devastating earthquake that hit Nepal in April this year have now returned, according to researchers who tracked mobile phone data to monitor the movement of those affected by the quake.

The Nepal earthquake that killed over 9,000 people and injured more than 23,000 was followed by about 300 aftershocks. An estimated 500,000 buildings were destroyed or severely damaged.

Researchers from the University of Southampton in UK used mobile phone data to monitor the movement of people affected by the earthquake and help with the continuing relief effort in Nepal.

Just a week after the disaster took place, the team began daily monitoring of anonymised phone data to track the displacement of populations in the affected areas.

Five months on, they are continuing to supply accurate, up-to-date reports to the United Nations.

“Although we have used mobile phone data before to measure population movements, this is the first time we have used the method in an ongoing ‘live’ situation,” said Andy Tatem, Professor of Geography at University of Southampton. “By watching how the population moves on a daily basis, we have been able to help directly with aid efforts and the rebuilding of infrastructures,” said Tatem. Every time a person uses a mobile it sends information to a receiving tower and gives an approximate location of where they are. When this information is repeated multiple times, over millions of users, a detailed picture can be extracted of population density, movement and how it changes over time in a given area. In Nepal, the researchers linked up with the country’s largest mobile phone operator to analyse anonymised data from 12 million mobiles across the country.