Some city neighborhoods are lush with parks and trees, but others are dominated by treeless stretches of concrete and pavement.

Areas with fewer trees to provide shade and less vegetation to soak up water tend to be hotter.

“They tend to be wetter, they tend to have worse air quality,” says Cate Mingoya of Groundwork USA, a network of environmental justice organizations.

She says these disparities result from decades of disinvestment and redlining: racist mortgage lending policies that reinforced segregation and worsened inequality.

Groundwork is helping residents in nine cities highlight the relationship between historical segregation and climate change vulnerability.

“Without a really clear understanding of the harms that have happened in the past, you can’t have a vision for the future and for how you’re going to repair that harm,” Mingoya says.

The group overlaid maps of historical redlining with data about heat, tree cover, and impermeable surfaces.

Mingoya says the maps show how the impacts of redlining persist, and provide an important tool for local residents, “to sit down with their local government, with elected officials, with leaders in their community and say, ‘You need to explain why this is still the case and you need to explain what you’re going to do to make things look a little bit different.'”

Also see: The link between racist housing policies of the past and the climate risks of today

Reporting credit: Sarah Kennedy/ChavoBart Digital Media.