Google Maps Building Reflectivity Data to 50+ Cities
Google Research is releasing a building-level rooftop reflectivity dataset covering more than 50 cities, paired with a new Earth Engine app, to help urban planners target cool-roof interventions.
Does Google have building-level cool-roof data for cities worldwide?
Yes. Google Research has expanded its Heat Resilience dataset from a 14-city pilot to more than 50 global cities. The dataset maps rooftop reflectivity at the individual building level and is now freely accessible through a new high-resolution Heat Resilience Earth Engine App.
Why rooftop reflectivity matters
Extreme heat causes roughly 500,000 deaths per year, according to figures cited in the announcement. Cities compound the problem through the urban heat island effect, which causes metropolitan areas to warm at double the global average rate.
Dark roofing materials and pavements, combined with limited vegetation, are primary drivers of that localized warming. Cool roofs increase a surface's albedo, meaning more solar energy is reflected rather than absorbed, which lowers surface temperatures in surrounding neighborhoods.
What the dataset covers
The methodology, published in Nature Communications under the title "Estimating high-resolution albedo for urban applications," fuses Sentinel-2 satellite data with 30-centimeter-resolution imagery from Airbus Pléiades Neo. That combination lets the model produce building-level readings rather than neighborhood-wide averages.
| Attribute | Detail |
|---|---|
| Cities covered | 50+ |
| Image resolution | 30 cm (Airbus Pléiades Neo) |
| Satellite data source | Sentinel-2 |
| Potential heat reduction | Up to 0.5°C (0.9°F) globally with targeted cool-roof planning |
| Access method | Heat Resilience Earth Engine App |
| Research publication | Nature Communications |
The paper is part of Google's broader Google Earth AI collection, described as a set of geospatial models and datasets intended to convert planetary imagery into actionable intelligence.
From pilot to policy
During the 2024 pilot with 14 cities, planners used the earlier dataset to identify vulnerable neighborhoods and determine where cool-roof installations would produce the greatest temperature reductions. The announcement notes that the data informed concrete policy outcomes in several of those cities, including cool-roof ordinances and formal adaptation plans.
Scaling to 50-plus cities significantly widens that policy surface. The dataset is designed to let planners move beyond general climate observations and make specific, block-by-block decisions about where reflective roofing would have the most impact.
How to access it
The dataset is open and available through the Heat Resilience Earth Engine App. Researchers can also access the underlying methodology through the Nature Communications paper. No API credentials or special application are mentioned as required beyond a standard Earth Engine account.
The release comes as Europe recorded temperatures above 40°C during heat waves earlier in June, underscoring the near-term demand for practical heat mitigation tools. Google's modeling suggests that if cities used this data to guide targeted cool-roof programs, urban surface temperatures could fall by as much as 0.5°C at the global scale, a figure that could translate to meaningfully lower heat-related mortality in dense urban areas.