Skip to main content
Version: 1.1.3

Urban Heat Island Analysis (UHI)

The Urban Heat Islands analysis identifies overheating zones across your territory by cross-referencing Land Cover data with imperviousness indicators.

Level 1 — Land Cover & derived analyses

This analysis is part of Level 1 of Fit Audit. Contact us to learn more.

How it works​

Urban heat islands are areas where the temperature is significantly higher than the surrounding spaces, mainly due to a high concentration of impervious surfaces (asphalt, concrete) and a lack of vegetation.

The CartograFit UHI analysis provides, for every satellite tile (~192 m across) of your territory:

  • The asphalt/vegetation ratio
  • An overall imperviousness index
  • A UHI score to help prioritize interventions
  • A map of priority hot spots

Use cases​

Greening programs​

Identify the zones where greening would have the greatest impact on thermal comfort. Prioritize your planting investments by targeting the most critical sectors.

RCO compliance (Overseas France)​

The Overseas Construction Regulation (RCO) sets albedo and thermal comfort standards for new buildings. The UHI analysis lets you check the compliance of existing zones.

Climate planning​

Feed your Territorial Climate-Air-Energy Plan (PCAET) with objective data on overheating zones. Track how your UHI score evolves over time.

Urban renewal​

As part of NPNRU or ACV programs, assess the thermal impact of renovation operations: before/after monitoring of the imperviousness index and the vegetation ratio.

Methodology​

The analysis draws on Land Cover data computed tile by tile from HD satellite imagery, cross-referenced with:

  • The proportion of dark surfaces (high thermal absorption)
  • The proportion of vegetation (cooling effect)
  • The built-up density (heat storage and release)

The UHI score synthesizes these indicators into a value from 0 (low risk) to 1 (high overheating risk).

Visualizing the results​

  • UHI heatmap: a heat map by satellite tile (from green to red)
  • Priority zones: identification of the sectors to address first
  • Neighborhood indicators: average score per administrative zone

Limits and caveats​

Disclaimer

The UHI score is an estimated indicator based on Land Cover, not a temperature measurement. It identifies zones at risk of overheating, but does not replace a full microclimate study.

Getting this analysis​

The UHI analysis is part of the Fit Audit — Territorial Analysis module.

✉️Contact us to activate this analysis