A city-wide network of low-cost temperature sensors has given researchers their most detailed picture yet of how heat lingers in dense, concrete-heavy districts well after sunset.
The data showed some neighbourhoods staying several degrees warmer than nearby parks into the early hours of the morning, a gap researchers attribute to building materials and a lack of tree cover.
Urban planners say the findings could help prioritise where to plant shade trees or install reflective roofing first, rather than spreading limited budgets evenly across a city.
The team plans to expand the sensor network next year to cover a wider set of neighbourhoods through a full summer season.