RESEARCH
Urban Heat Islands
A city is a patchwork of climates.
+4.1 °C warmer than the countryside at night
Large roofs and paved yards; the hottest surfaces in the city.
How we study it
- 01
Measure
Rooftop stations and cycling transects at night.
- 02
Map
Satellite land-surface temperature corrected to 1 km.
- 03
Test
What-if runs: more trees, cool roofs, wider streets.
Key findings
- 01
Up to 4 °C at night
The industrial belt stays warmest after sunset.
- 02
Trees cool streets
Every 10% of canopy lowers night heat by about 0.3 °C.
- 03
Rivers help — a little
River breezes cool only the first two blocks.
Related papers
- 2026
Nighttime heatwaves are lengthening faster than daytime ones in East Asian cities
- 2026
A 1 km urban heat-island dataset for 41 Korean cities, 2001–2025
- 2026
열대야 지속 기간의 도시 규모 의존성
- 2025
Street trees and the timing of peak heat stress