How green are Asia's cities?
Tree cover makes cities more livable, especially as heat waves become more common with climate change. DW has analysed the tree coverage in more than 40 major cities across Asia
Tree cover in urban spaces has a major effect on health and well-being, as trees can lower extreme temperatures and boost the mental and physical health of residents.
"We don't have a lot of greenery where we live. There are streets that have trees and parks that are green, but they are not enough. It makes our city very hot," said Fatima Irfan Shaikh from Karachi, Pakistan's largest city.
A DW data analysis of tree coverage in 41 major Asian cities shows a high level of variation.
While most people in metropolitan regions such as Colombo, in Sri Lanka, and Yangon, Myanmar live in neighbourhoods with high tree coverage, it's the opposite in places like Karachi, or in India's capital, New Delhi.
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And in the metropolitan area of Bangladesh's capital, Dhaka, a quarter of the city's 24 million people live in areas with virtually no trees at all.
Compared with European and North American cities, there is overall less tree coverage in Asian cities.
Green Mumbai, bare Beijing
India's Mumbai Metropolitan Region is one of the most tree-friendly urban centres in this analysis, with most residents living in areas with around 20% tree coverage. While areas in Mumbai proper are highly dense and tree-friendly, like Tardeo and Anushakti Nagar, the lush zones are usually in the suburbs.
However, Mayuresh Ghash, an ecologist in Mumbai, told DW that tree cover in the city is unevenly distributed, and that development threatens green spaces.
"Developing patches won't help ... we need to focus on the entire area," he said, adding that cutting down trees to make way for development in Mumbai is problematic because wildlife is not taken into account and saplings cannot replace old trees.
Mumbai's lush tree coverage is rare for Asian metropolises. Many cities usually have tree coverage similar to Beijing.
Most Beijing residents live in areas with around 10% tree coverage. An example can be seen in aerial images of Chaoyang district, a neighbourhood where many foreign embassies, international organisations and the biggest park in Beijing are located.
Can urban areas be both dense and green?
But even in densely populated residential areas, or places not conducive to tree growth, incorporating greening plans into urban developments can be beneficial to a city's residents as well as its environment.
A 2023 study argued that cities can be both green and dense if urban planners choose to make the most of the available solutions.
Singapore is a leader in green urban development. As a high-density country, it has prioritised urban green spaces in city planning.
For example, Singapore has built major thoroughfares requiring verges to be set aside for tree planting, Chua Yen Ling, group director for corporate strategy and planning at the National Parks Board of Singapore, told DW.
Singapore has also come up with creative green city solutions, such as vertical green walls and rooftop gardens.
Which cities are most in need of trees?
In Tokyo, the most populated city in the world, around 40% of the population live in neighbourhoods with almost no trees.
However, among the Asian metropolises analysed, nowhere aside from Gulf desert cities is more in need of trees than Pakistan's Karachi, where 80% of people have barely any tree coverage near their homes.
Karachi's arid climate is partly to blame, but in comparable cities such as Kabul and Tehran, there are more trees.
Javed Ahmed Mahar from the Sindh Wildlife Department said apart from Karachi's arid climate, the growing population and uncontrolled urban development also pose challenges to the city's share of tree cover.
While there are green initiatives in Karachi, Mahar told DW that more needs to be done to preserve green spaces and wetlands, and more urban planners need to "scientifically" carry out tree planting projects.
How much does geography matter?
The 41 Asian cities analysed span through biomes that range from tropical forests to deserts, and climates from tropic monsoon to arid zones.
Indeed, climate, terrain and biome play an important role in tree coverage. The top three cities, Colombo, Yangon and Mumbai, all have a tropical climate, which naturally favours more green spaces. Cities in desert regions usually have sparse tree coverage.
But cities in roughly the same climate and biome can often have different tree coverage levels.
Manila, located in the Philippines, has most of its population living in treeless areas, in contrast with Yangon, with a similar climate in Myanmar.
How trees make cities more livable
Earlier this year, many parts of Asia experienced record-high temperatures. India, for example, faced its worst heat wave in over a decade, with temperatures soaring above 50 degrees Celsius (122 Fahrenheit) in New Delhi.
Adding more trees in extremely exposed areas can be the difference between life and death for many people. India's Health Ministry said 110 people died of heatstroke between March and June of 2024.
Trees and other vegetation can also act like sponges — soaking up water naturally, holding and releasing it back into the water cycle.
Many places around the world are trying to become "sponge cities" by turning away from traditionally designing buildings and surfaces with concrete and asphalt which do not allow water to drain. China is leading the way.
In cities such as Colombo, Mumbai and Singapore, most people live in areas with tree coverage comparable to that seen in more developed countries.
On average, Europe and North America have made more space for trees in their cities than the rest of the world. In general, cities in countries with a higher economic development level had lusher tree coverage.
However, the majority of Asian metropolises are closer to levels in Africa and Latin America.
As urban greenery plays an important role in promoting well-being of city dwellers, reducing the wealth gap might also require cities to boost tree coverage in more neighbourhoods.
DW's data relied on satellite observations that include entire metropolitan areas instead of official administrative boundaries.
Emmy Sasipornkarn is a freelance journalist working for DW. She writes articles about Southeast Asia with a focus on Thailand.
Rodrigo Menegat Schuinski is a data journalist at Deutsche Welle.
Disclaimer: This article first appeared on DW, and is published by special syndication arrangement.
