Singapore, August 26, 2026: Singapore’s decades-long effort to plant and preserve millions of trees is delivering measurable benefits with new research showing that urban greenery can cool streets, reduce heat stress and lower the demand for air conditioning in one of Asia’s hottest and most densely built cities.
A study conducted in Singapore’s one north district found that street shade reduced average air temperatures by around 0.8°C across 20 paired sunlit and shaded locations. The impact on human heat stress was even greater.
Using the Universal Thermal Climate Index, which considers temperature, humidity, wind and radiant heat, researchers found that shade reduced perceived heat stress by an average of 3.1°C and prevented around 92% of extreme heat stress that would otherwise have occurred at the studied locations.
The findings highlight the importance of trees not simply as decorative elements but as essential urban infrastructure.
Singapore has spent decades developing its reputation as a “City in Nature,” planting trees along roads, around buildings and throughout public spaces. The research suggests that this green infrastructure is becoming increasingly valuable as cities face rising temperatures and growing energy demands.
Trees also help reduce the burden on air conditioning systems. By shading building facades and blocking solar radiation before it reaches walls, vegetation can reduce the amount of heat entering buildings.
Research and modelling cited in the study suggest that greenery around buildings can significantly lower cooling demand. Simulations involving vegetation on building facades in Singapore indicated cooling load reductions ranging from approximately 10% to 31% depending on the density and coverage of the foliage.
A wider assessment of Singapore’s urban vegetation estimated that natural cooling from greenery could reduce public housing energy use by around 228 gigawatt hours per year, potentially saving about S$47 million annually.
However, researchers caution that trees are not a complete solution to urban heat. Singapore’s humid tropical climate limits the cooling effect of evapotranspiration, while excessively dense tree cover can reduce airflow and trap humidity and pollutants.
This means urban planning must focus not only on planting more trees but also on planting them strategically.
The combination of tree canopy, shelters and building overhangs may provide even greater protection from extreme heat. Researchers suggest that well designed shaded areas could reduce temperatures and heat exposure by 3°C to 5°C in some locations.
Singapore is continuing to expand its urban forest through the OneMillionTrees movement, launched in 2020 with the goal of planting one million additional trees by the end of the decade and increasing the country’s total tree population to more than eight million.
Smaller green spaces may also play an important role. Research presented in 2026 found that a dense microforest outside City Square Mall, occupying an area roughly the size of a basketball court cooled its immediate surroundings by as much as 5°C while supporting significantly greater biodiversity than a nearby grass covered area.
The findings suggest that in land scarce cities, even small and overlooked spaces could become valuable climate infrastructure.
As global temperatures rise and air conditioning demand places increasing pressure on electricity grids, Singapore’s experience offers a simple lesson trees may be one of the most effective pieces of infrastructure a hot city can build.