How smartphones enable us to observe the largest seasonal migration of people in the world

Every year between January and February the largest seasonal migration in the world takes place – Spring Festival, known in the West as Chinese New Year. For many migrant workers, the 11 day statutory holiday is the one time of year they have enough time off work to be able to make the journey home to see their families in the countryside and as such huge numbers of journeys are made by a variety of means. The Chinese Ministry of Transport recorded a record number of journeys on public transport in 2013: 3.42 billion were made in total with more trips made by private means. What is different this year is that it is the first time this mass movement can be can be visualised and tracked almost in real time.

Baidu (the Chinese equivalent of Google) launched Baidu Migrate earlier this month. Baidu Migrate is an interactive heat map which shows the most popular tourist routes during the holiday season by creating a web of blue lines – the thicker ones representing the more popular routes, the thinner ones showing the less popular ones – across China.

The application is updated every four to eight hours using data from location logins on the smart phone application Baidu Maps. This application has 200 million registered users and a daily tally of 3.5 billion location requests, making the data both representative of the pattern of journeys being made each day and also near real-time in its accuracy.

The Baidu Migrate map tells us a number of things about the movement and flow of people. It exposes and exemplifies the long-term migration patterns of China’s citizens from the countryside to urban centres (as visualised by McKinsey). Unsurprisingly, the largest number of departures recorded on the map yesterday were from large manufacturing hubs such as Guangzhou, Beijing and Shanghai. The most popular destinations were transport hubs such as Hengyang where people can make onward trips to the countryside, tourist cities such as Chongqing and Beijing (Spring Festival is also a time for cultural visits) as well as cities that have seen a large out pouring of workers in recent years.

Tracking the movement and flow of people and individuals, though controversial, is very important. It can provide important insight into patterns of behaviour and where countries and companies need to expand or reduce capacity. Last April, for example, IBM developed a new model for urban transport in the Ivory Coast based on mobile phone data to make the routes more optimal. Will China be able to do the same? Next New Year will the Chinese Ministry of Transport have reacted to this travel map, increased the capacity and improved the flow of congested transport lines?