- Commute times to cities is a global indicator of development and access to opportunity
- New data from Google and Open Street Map have improved data about transportation networks worldwide
- More accurate maps will help development aid reach communities most in need
The length of your daily commute may determine whether you’re able to get through one podcast or two before you reach your front door, but it can also be a reliable indicator of access to opportunity.
Around the world, economic and educational resources, as well as health and financial services, are concentrated in cities. The longer it takes an individual to travel to an urban center, the more limited their access to those services.
Countries with pervasively limited access to metropolitan areas are much more likely to face greater barriers to development. Eliminating these disparities is the aim of The United Nations 2030 Agenda for Sustainable Development, which commits to applying development goals equally across all nations in order to “leave no one behind”.
But to achieve this ambition, officials and agencies need a way to measure and compare current circumstances across nations.
Daniel Weiss of the Malaria Atlas Project at the University of Oxford has previously investigated the global landscape of malaria risk. Now, in collaboration with Google, the Joint Research Centre for the European Union, and the University of Twente, Weiss has created a series of maps illustrating global accessibility to cities in 2015.
In the decade since the last attempt to measure urban accessibility worldwide, new data sources provided by Open Street Map and Google have become available, capturing transportation networks with unprecedented detail.
“The new data has resulted in a nearly five-fold increase in mapped road area relative to that used the last time a map like this was created in 2008,” says Weiss. “And the improvements are most prominent in areas where quality data are most needed for informing sustainable development policies and actions.”
But because simply calculating distance doesn’t reflect variations in terrain, infrastructure, and the ease with which people traverse those distances, Weiss’s maps reflect actual travel time—a more practical measure of access than distance, and a more human one.
Who gets there faster
Eighty percent of the global population—nearly 6 billion individuals—live within one hour of cities, but accessibility is not equally distributed.
Only half of individuals living in low-income settings live within an hour of a city, mainly in sub-Saharan Africa, compared with more than 90 percent of people in high-income countries, primarily in Europe and North America.
Somewhat intuitively, ease of access to cities generally correlates to countries with high income, but this is not always the case.
For example, India has a relatively low GDP per capita, but its high population density and numerous cities mean that commute times are almost universally below one hour except in the mountainous regions on its northern border.
Saudi Arabia demonstrates a reverse case. Though it’s a high-income country with a very urban population, travel times to cities are some of the longest in the study, with swathes of the country having commute times equal to a day or more.
However, Weiss cautions that despite the potentially beneficial aspects of short travel times to cities for humans, greater accessibility has an associated environmental cost owing to the relative ease with which humans can extract natural resources in places closer to population centers.
Past research has shown that building new roads in wilderness areas like the Amazon Basin leads to outcomes such as deforestation, human settlement, and ultimately the end of the wilderness that previously existed. For example, in Brazil, the majority of deforestation occurs within one to five hours’ travel time from cities.
“While a key message of our paper is that greater accessibility to cities is correlated with better conditions (on average) for humans, we also note that there are costs associated with increasing accessibility,” says Weiss.
Weiss emphasizes that while he and his team support increasing accessibility as a means of benefiting human populations, they are equally strong proponents of sensible development strategies that balance needs of people with goals such as maintaining biodiversity.
Ultimately, the global commute time maps provide empirical evidence for relationships hypothesized to be important in many research areas. Because the maps are made with a globally-consistent methodology, they support assessments of how human well-being varies between countries and regions.
“Our hope is that people will use our map, or create maps of their own using the data and code we freely provide, to make better informed planning and policy decisions, and thus improve people's lives by providing them with easier access to goods and services they need,” says Weiss.