While climate change contributes to larger and more devastating natural disasters, the aftermath of a flood or a hurricane can be exacerbated by how cities and villages are built–which is often shaped by policy. While President Trump has decided to withdraw the U.S. from the Paris Climate Agreement, the European Union is continuing to fund research to answer questions about how to mitigate the impact of a changing climate on global human settlement.
The latest evidence of how committed the European Union is to actively studying how to adapt to a changing climate? The Atlas of the Human Planet 2017. In the new report, researchers at the European Commission’s Joint Research Center looked at six types of natural hazards–earthquakes, volcanoes, tsunamis, floods, hurricanes, and sea level surge–to show how the global population’s exposure to these risks has doubled in the last 40 years.
The Atlas relies on the Global Human Settlement Layer, a dataset that combines satellite imaging data of the planet’s built environments with estimations of how many people actually live in each area across four decades, showing the growth of human settlements across the decades. After completing the GHSL dataset for the 2016 version of the Atlas of the Human Planet, the team is using the data to look into disaster risk across the globe, with a plan to continue using it for a different Atlas theme each year.
“Because satellite data is very systematic and consistent, it’s a unique source to make a more systematic census,” says Martino Pesaresi, one of the researchers and authors of the atlas. “For the first time in human history we’re able to observe how humans were building their cities in an objective and systematic way.”
The researchers used their data on the number of people living in different areas of the world, combined with the built environment around them, to calculate levels of exposure. Of the six hazards they looked at, earthquakes have the greatest potential impact–while in 1975 1.4 billion people were at risk, 2.7 billion were at risk in 2015. Floods happen the most frequently, but they impact Asia and Africa much more heavily, with Asia accounting for 76.9% of the exposed population of the world and Africa accounting for 12.2%. Japan is most at risk from tsunamis, while Indonesia is most vulnerable to volcanoes.
While the researchers said that these findings–which they presented at the 2017 Global Platform for Disaster Risk Reduction conference in Cancun, Mexico–aren’t directly tied to climate change policy, they point to vulnerabilities that are created by the way cities are designed and built. While they can’t yet point to what those are, the next step in the research is to create a detailed understanding of how city planning impacts each urban center’s vulnerability to disaster. “It’s less about the climate, more about mitigation measures,” says Pesaresi.
Research like this, that studies how vulnerable different areas are affected by disasters, provides a scientific grounding for policymakers to help protect their countries. The Global Human Settlement Layer data is open source, and Pesaresi and the research team hope that other scientists will verify their work and use the data to more deeply inform both climate change policy and urban development policy.
As President Trump tries to cut science funding and begins the four-year process to withdraw from the Paris Climate Agreement, this kind of research is more important than ever.